[DUBBO-3137]: step3 - start using CommonConstants (#4030)

* [DUBBO-3137]: start to use org.apache.dubbo.common.constants.CommonConstants

* remove useless imports

* remove useless imports

* remove unused imports

* remove unused imports

* remove unused imports

* remove unused imports

* remove unused imports

* use static import

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/Configurator.java

@@ -28,6 +28,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_KEY;
+
 /**
  * Configurator. (SPI, Prototype, ThreadSafe)
  *
@@ -82,7 +84,7 @@ public interface Configurator extends Comparable<Configurator> {
             }
             Map<String, String> override = new HashMap<>(url.getParameters());
             //The anyhost parameter of override may be added automatically, it can't change the judgement of changing url
-            override.remove(Constants.ANYHOST_KEY);
+            override.remove(ANYHOST_KEY);
             if (override.size() == 0) {
                 configurators.clear();
                 continue;

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/configurator/AbstractConfigurator.java

@@ -27,6 +27,16 @@ import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.ANY_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER;
+import static org.apache.dubbo.common.constants.CommonConstants.ENABLED_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * AbstractOverrideConfigurator
  */
@@ -49,7 +59,7 @@ public abstract class AbstractConfigurator implements Configurator {
     @Override
     public URL configure(URL url) {
         // If override url is not enabled or is invalid, just return.
-        if (!configuratorUrl.getParameter(Constants.ENABLED_KEY, true) || configuratorUrl.getHost() == null || url == null || url.getHost() == null) {
+        if (!configuratorUrl.getParameter(ENABLED_KEY, true) || configuratorUrl.getHost() == null || url == null || url.getHost() == null) {
             return url;
         }
         /**
@@ -57,11 +67,11 @@ public abstract class AbstractConfigurator implements Configurator {
          */
         String apiVersion = configuratorUrl.getParameter(Constants.CONFIG_VERSION_KEY);
         if (StringUtils.isNotEmpty(apiVersion)) {
-            String currentSide = url.getParameter(Constants.SIDE_KEY);
-            String configuratorSide = configuratorUrl.getParameter(Constants.SIDE_KEY);
-            if (currentSide.equals(configuratorSide) && Constants.CONSUMER.equals(configuratorSide) && 0 == configuratorUrl.getPort()) {
+            String currentSide = url.getParameter(SIDE_KEY);
+            String configuratorSide = configuratorUrl.getParameter(SIDE_KEY);
+            if (currentSide.equals(configuratorSide) && CONSUMER.equals(configuratorSide) && 0 == configuratorUrl.getPort()) {
                 url = configureIfMatch(NetUtils.getLocalHost(), url);
-            } else if (currentSide.equals(configuratorSide) && Constants.PROVIDER.equals(configuratorSide) && url.getPort() == configuratorUrl.getPort()) {
+            } else if (currentSide.equals(configuratorSide) && PROVIDER.equals(configuratorSide) && url.getPort() == configuratorUrl.getPort()) {
                 url = configureIfMatch(url.getHost(), url);
             }
         }
@@ -84,41 +94,41 @@ public abstract class AbstractConfigurator implements Configurator {
         } else {// override url don't have a port, means the ip override url specify is a consumer address or 0.0.0.0
             // 1.If it is a consumer ip address, the intention is to control a specific consumer instance, it must takes effect at the consumer side, any provider received this override url should ignore;
             // 2.If the ip is 0.0.0.0, this override url can be used on consumer, and also can be used on provider
-            if (url.getParameter(Constants.SIDE_KEY, Constants.PROVIDER).equals(Constants.CONSUMER)) {
+            if (url.getParameter(SIDE_KEY, PROVIDER).equals(CONSUMER)) {
                 return configureIfMatch(NetUtils.getLocalHost(), url);// NetUtils.getLocalHost is the ip address consumer registered to registry.
-            } else if (url.getParameter(Constants.SIDE_KEY, Constants.CONSUMER).equals(Constants.PROVIDER)) {
-                return configureIfMatch(Constants.ANYHOST_VALUE, url);// take effect on all providers, so address must be 0.0.0.0, otherwise it won't flow to this if branch
+            } else if (url.getParameter(SIDE_KEY, CONSUMER).equals(PROVIDER)) {
+                return configureIfMatch(ANYHOST_VALUE, url);// take effect on all providers, so address must be 0.0.0.0, otherwise it won't flow to this if branch
             }
         }
         return url;
     }
 
     private URL configureIfMatch(String host, URL url) {
-        if (Constants.ANYHOST_VALUE.equals(configuratorUrl.getHost()) || host.equals(configuratorUrl.getHost())) {
+        if (ANYHOST_VALUE.equals(configuratorUrl.getHost()) || host.equals(configuratorUrl.getHost())) {
             // TODO, to support wildcards
             String providers = configuratorUrl.getParameter(Constants.OVERRIDE_PROVIDERS_KEY);
-            if (StringUtils.isEmpty(providers) || providers.contains(url.getAddress()) || providers.contains(Constants.ANYHOST_VALUE)) {
-                String configApplication = configuratorUrl.getParameter(Constants.APPLICATION_KEY,
+            if (StringUtils.isEmpty(providers) || providers.contains(url.getAddress()) || providers.contains(ANYHOST_VALUE)) {
+                String configApplication = configuratorUrl.getParameter(APPLICATION_KEY,
                         configuratorUrl.getUsername());
-                String currentApplication = url.getParameter(Constants.APPLICATION_KEY, url.getUsername());
-                if (configApplication == null || Constants.ANY_VALUE.equals(configApplication)
+                String currentApplication = url.getParameter(APPLICATION_KEY, url.getUsername());
+                if (configApplication == null || ANY_VALUE.equals(configApplication)
                         || configApplication.equals(currentApplication)) {
                     Set<String> conditionKeys = new HashSet<String>();
                     conditionKeys.add(Constants.CATEGORY_KEY);
                     conditionKeys.add(RemotingConstants.CHECK_KEY);
                     conditionKeys.add(Constants.DYNAMIC_KEY);
-                    conditionKeys.add(Constants.ENABLED_KEY);
-                    conditionKeys.add(Constants.GROUP_KEY);
-                    conditionKeys.add(Constants.VERSION_KEY);
-                    conditionKeys.add(Constants.APPLICATION_KEY);
-                    conditionKeys.add(Constants.SIDE_KEY);
+                    conditionKeys.add(ENABLED_KEY);
+                    conditionKeys.add(GROUP_KEY);
+                    conditionKeys.add(VERSION_KEY);
+                    conditionKeys.add(APPLICATION_KEY);
+                    conditionKeys.add(SIDE_KEY);
                     conditionKeys.add(Constants.CONFIG_VERSION_KEY);
                     for (Map.Entry<String, String> entry : configuratorUrl.getParameters().entrySet()) {
                         String key = entry.getKey();
                         String value = entry.getValue();
-                        if (key.startsWith("~") || Constants.APPLICATION_KEY.equals(key) || Constants.SIDE_KEY.equals(key)) {
+                        if (key.startsWith("~") || APPLICATION_KEY.equals(key) || SIDE_KEY.equals(key)) {
                             conditionKeys.add(key);
-                            if (value != null && !Constants.ANY_VALUE.equals(value)
+                            if (value != null && !ANY_VALUE.equals(value)
                                     && !value.equals(url.getParameter(key.startsWith("~") ? key.substring(1) : key))) {
                                 return url;
                             }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/configurator/parser/ConfigParser.java

@@ -31,6 +31,8 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+
 /**
  * Config parser
  */
@@ -194,7 +196,7 @@ public class ConfigParser {
             addresses = new ArrayList<>();
         }
         if (addresses.size() == 0) {
-            addresses.add(Constants.ANYHOST_VALUE);
+            addresses.add(ANYHOST_VALUE);
         }
         return addresses;
     }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/ConsistentHashLoadBalance.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.rpc.cluster.loadbalance;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.rpc.Invocation;
 import org.apache.dubbo.rpc.Invoker;
@@ -31,6 +30,8 @@ import java.util.TreeMap;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+
 /**
  * ConsistentHashLoadBalance
  */
@@ -78,7 +79,7 @@ public class ConsistentHashLoadBalance extends AbstractLoadBalance {
             this.identityHashCode = identityHashCode;
             URL url = invokers.get(0).getUrl();
             this.replicaNumber = url.getMethodParameter(methodName, HASH_NODES, 160);
-            String[] index = Constants.COMMA_SPLIT_PATTERN.split(url.getMethodParameter(methodName, HASH_ARGUMENTS, "0"));
+            String[] index = COMMA_SPLIT_PATTERN.split(url.getMethodParameter(methodName, HASH_ARGUMENTS, "0"));
             argumentIndex = new int[index.length];
             for (int i = 0; i < index.length; i++) {
                 argumentIndex[i] = Integer.parseInt(index[i]);

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/router/condition/ConditionRouter.java

@@ -39,6 +39,11 @@ import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import static org.apache.dubbo.common.constants.CommonConstants.METHOD_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY_PREFIX;
+import static org.apache.dubbo.common.constants.CommonConstants.ENABLED_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.METHODS_KEY;
+
 /**
  * ConditionRouter
  *
@@ -63,7 +68,7 @@ public class ConditionRouter extends AbstractRouter {
         this.url = url;
         this.priority = url.getParameter(Constants.PRIORITY_KEY, 0);
         this.force = url.getParameter(Constants.FORCE_KEY, false);
-        this.enabled = url.getParameter(Constants.ENABLED_KEY, true);
+        this.enabled = url.getParameter(ENABLED_KEY, true);
         init(url.getParameterAndDecoded(Constants.RULE_KEY));
     }
 
@@ -219,7 +224,7 @@ public class ConditionRouter extends AbstractRouter {
             String key = matchPair.getKey();
             String sampleValue;
             //get real invoked method name from invocation
-            if (invocation != null && (Constants.METHOD_KEY.equals(key) || Constants.METHODS_KEY.equals(key))) {
+            if (invocation != null && (METHOD_KEY.equals(key) || METHODS_KEY.equals(key))) {
                 sampleValue = invocation.getMethodName();
             } else if (Constants.ADDRESS_KEY.equals(key)) {
                 sampleValue = url.getAddress();
@@ -228,7 +233,7 @@ public class ConditionRouter extends AbstractRouter {
             } else {
                 sampleValue = sample.get(key);
                 if (sampleValue == null) {
-                    sampleValue = sample.get(Constants.DEFAULT_KEY_PREFIX + key);
+                    sampleValue = sample.get(DEFAULT_KEY_PREFIX + key);
                 }
             }
             if (sampleValue != null) {

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/router/condition/config/AppRouter.java

@@ -16,8 +16,8 @@
  */
 package org.apache.dubbo.rpc.cluster.router.condition.config;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.configcenter.DynamicConfiguration;
 
 /**
@@ -31,7 +31,7 @@ public class AppRouter extends ListenableRouter {
     private static final int APP_ROUTER_DEFAULT_PRIORITY = 150;
 
     public AppRouter(DynamicConfiguration configuration, URL url) {
-        super(configuration, url, url.getParameter(Constants.APPLICATION_KEY));
+        super(configuration, url, url.getParameter(CommonConstants.APPLICATION_KEY));
         this.priority = APP_ROUTER_DEFAULT_PRIORITY;
     }
 }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/router/tag/TagRouter.java

@@ -18,6 +18,7 @@ package org.apache.dubbo.rpc.cluster.router.tag;
 
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.CollectionUtils;
@@ -232,7 +233,7 @@ public class TagRouter extends AbstractRouter implements ConfigurationListener {
 
         Invoker<T> invoker = invokers.get(0);
         URL url = invoker.getUrl();
-        String providerApplication = url.getParameter(Constants.REMOTE_APPLICATION_KEY);
+        String providerApplication = url.getParameter(CommonConstants.REMOTE_APPLICATION_KEY);
 
         if (StringUtils.isEmpty(providerApplication)) {
             logger.error("TagRouter must getConfig from or subscribe to a specific application, but the application " +

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/ClusterUtils.java

@@ -26,6 +26,21 @@ import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ALIVE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY_PREFIX;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.METHODS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.RELEASE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.REMOTE_APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADPOOL_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMESTAMP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * ClusterUtils
  */
@@ -42,29 +57,29 @@ public class ClusterUtils {
             map.putAll(remoteMap);
 
             // Remove configurations from provider, some items should be affected by provider.
-            map.remove(Constants.THREAD_NAME_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.THREAD_NAME_KEY);
+            map.remove(THREAD_NAME_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + THREAD_NAME_KEY);
 
-            map.remove(Constants.THREADPOOL_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.THREADPOOL_KEY);
+            map.remove(THREADPOOL_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + THREADPOOL_KEY);
 
-            map.remove(Constants.CORE_THREADS_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.CORE_THREADS_KEY);
+            map.remove(CORE_THREADS_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + CORE_THREADS_KEY);
 
-            map.remove(Constants.THREADS_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.THREADS_KEY);
+            map.remove(THREADS_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + THREADS_KEY);
 
-            map.remove(Constants.QUEUES_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.QUEUES_KEY);
+            map.remove(QUEUES_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + QUEUES_KEY);
 
-            map.remove(Constants.ALIVE_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.ALIVE_KEY);
+            map.remove(ALIVE_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + ALIVE_KEY);
 
             map.remove(RemotingConstants.TRANSPORTER_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + RemotingConstants.TRANSPORTER_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + RemotingConstants.TRANSPORTER_KEY);
 
             map.remove(Constants.ASYNC_KEY);
-            map.remove(Constants.DEFAULT_KEY_PREFIX + Constants.ASYNC_KEY);
+            map.remove(DEFAULT_KEY_PREFIX + Constants.ASYNC_KEY);
 
             // remove method async entry.
             Set<String> methodAsyncKey = new HashSet<>();
@@ -82,28 +97,28 @@ public class ClusterUtils {
             // All providers come to here have been filtered by group, which means only those providers that have the exact same group value with the consumer could come to here.
             // So, generally, we don't need to care about the group value here.
             // But when comes to group merger, there is an exception, the consumer group may be '*' while the provider group can be empty or any other values.
-            String remoteGroup = map.get(Constants.GROUP_KEY);
-            String remoteRelease = map.get(Constants.RELEASE_KEY);
+            String remoteGroup = map.get(GROUP_KEY);
+            String remoteRelease = map.get(RELEASE_KEY);
             map.putAll(localMap);
             if (StringUtils.isNotEmpty(remoteGroup)) {
-                map.put(Constants.GROUP_KEY, remoteGroup);
+                map.put(GROUP_KEY, remoteGroup);
             }
             // we should always keep the Provider RELEASE_KEY not overrode by the the value on Consumer side.
-            map.remove(Constants.RELEASE_KEY);
+            map.remove(RELEASE_KEY);
             if (StringUtils.isNotEmpty(remoteRelease)) {
-                map.put(Constants.RELEASE_KEY, remoteRelease);
+                map.put(RELEASE_KEY, remoteRelease);
             }
         }
         if (remoteMap != null && remoteMap.size() > 0) {
             // Use version passed from provider side
             reserveRemoteValue(Constants.DUBBO_VERSION_KEY, map, remoteMap);
-            reserveRemoteValue(Constants.VERSION_KEY, map, remoteMap);
-            reserveRemoteValue(Constants.METHODS_KEY, map, remoteMap);
-            reserveRemoteValue(Constants.TIMESTAMP_KEY, map, remoteMap);
+            reserveRemoteValue(VERSION_KEY, map, remoteMap);
+            reserveRemoteValue(METHODS_KEY, map, remoteMap);
+            reserveRemoteValue(TIMESTAMP_KEY, map, remoteMap);
             reserveRemoteValue(Constants.TAG_KEY, map, remoteMap);
             // TODO, for compatibility consideration, we cannot simply change the value behind APPLICATION_KEY from Consumer to Provider. So just add an extra key here.
             // Reserve application name from provider.
-            map.put(Constants.REMOTE_APPLICATION_KEY, remoteMap.get(Constants.APPLICATION_KEY));
+            map.put(REMOTE_APPLICATION_KEY, remoteMap.get(APPLICATION_KEY));
 
             // Combine filters and listeners on Provider and Consumer
             String remoteFilter = remoteMap.get(Constants.REFERENCE_FILTER_KEY);
@@ -130,4 +145,4 @@ public class ClusterUtils {
         }
     }
 
-}
+}

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/ForkingClusterInvoker.java

@@ -35,6 +35,9 @@ import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_TIMEOUT;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+
 /**
  * Invoke a specific number of invokers concurrently, usually used for demanding real-time operations, but need to waste more service resources.
  *
@@ -60,7 +63,7 @@ public class ForkingClusterInvoker<T> extends AbstractClusterInvoker<T> {
             checkInvokers(invokers, invocation);
             final List<Invoker<T>> selected;
             final int forks = getUrl().getParameter(Constants.FORKS_KEY, Constants.DEFAULT_FORKS);
-            final int timeout = getUrl().getParameter(Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT);
+            final int timeout = getUrl().getParameter(TIMEOUT_KEY, DEFAULT_TIMEOUT);
             if (forks <= 0 || forks >= invokers.size()) {
                 selected = invokers;
             } else {

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/MergeableClusterInvoker.java

@@ -47,6 +47,10 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_TIMEOUT;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+
 @SuppressWarnings("unchecked")
 public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
 
@@ -68,7 +72,7 @@ public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
                         return invoker.invoke(invocation);
                     } catch (RpcException e) {
                         if (e.isNoInvokerAvailableAfterFilter()) {
-                            log.debug("No available provider for service" + directory.getUrl().getServiceKey() + " on group " + invoker.getUrl().getParameter(Constants.GROUP_KEY) + ", will continue to try another group.");
+                            log.debug("No available provider for service" + directory.getUrl().getServiceKey() + " on group " + invoker.getUrl().getParameter(GROUP_KEY) + ", will continue to try another group.");
                         } else {
                             throw e;
                         }
@@ -101,7 +105,7 @@ public class MergeableClusterInvoker<T> extends AbstractClusterInvoker<T> {
 
         List<Result> resultList = new ArrayList<Result>(results.size());
 
-        int timeout = getUrl().getMethodParameter(invocation.getMethodName(), Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT);
+        int timeout = getUrl().getMethodParameter(invocation.getMethodName(), TIMEOUT_KEY, DEFAULT_TIMEOUT);
         for (Map.Entry<String, Future<Result>> entry : results.entrySet()) {
             Future<Result> future = entry.getValue();
             try {

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/support/RegistryAwareClusterInvoker.java

@@ -28,6 +28,8 @@ import org.apache.dubbo.rpc.cluster.LoadBalance;
 
 import java.util.List;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY;
+
 /**
  *
  */
@@ -44,7 +46,7 @@ public class RegistryAwareClusterInvoker<T> extends AbstractClusterInvoker<T> {
     public Result doInvoke(Invocation invocation, final List<Invoker<T>> invokers, LoadBalance loadbalance) throws RpcException {
         // First, pick the invoker (XXXClusterInvoker) that comes from the local registry, distinguish by a 'default' key.
         for (Invoker<T> invoker : invokers) {
-            if (invoker.isAvailable() && invoker.getUrl().getParameter(Constants.REGISTRY_KEY + "." + Constants.DEFAULT_KEY, false)) {
+            if (invoker.isAvailable() && invoker.getUrl().getParameter(Constants.REGISTRY_KEY + "." + DEFAULT_KEY, false)) {
                 return invoker.invoke(invocation);
             }
         }

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/configurator/parser/ConfigParserTest.java

@@ -31,6 +31,11 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  *
  */
@@ -76,8 +81,8 @@ public class ConfigParserTest {
             Assertions.assertNotNull(urls);
             Assertions.assertEquals(1, urls.size());
             URL url = urls.get(0);
-            Assertions.assertEquals("testgroup", url.getParameter(Constants.GROUP_KEY));
-            Assertions.assertEquals("1.0.0", url.getParameter(Constants.VERSION_KEY));
+            Assertions.assertEquals("testgroup", url.getParameter(GROUP_KEY));
+            Assertions.assertEquals("1.0.0", url.getParameter(VERSION_KEY));
         }
     }
 
@@ -89,8 +94,8 @@ public class ConfigParserTest {
             Assertions.assertEquals(4, urls.size());
             URL url = urls.get(0);
             Assertions.assertEquals("127.0.0.1", url.getAddress());
-            Assertions.assertEquals(6666, url.getParameter(Constants.TIMEOUT_KEY, 0));
-            Assertions.assertNotNull(url.getParameter(Constants.APPLICATION_KEY));
+            Assertions.assertEquals(6666, url.getParameter(TIMEOUT_KEY, 0));
+            Assertions.assertNotNull(url.getParameter(APPLICATION_KEY));
         }
     }
 
@@ -114,9 +119,9 @@ public class ConfigParserTest {
             URL url = urls.get(0);
             Assertions.assertEquals("127.0.0.1", url.getAddress());
             Assertions.assertEquals("service1", url.getServiceInterface());
-            Assertions.assertEquals(6666, url.getParameter(Constants.TIMEOUT_KEY, 0));
+            Assertions.assertEquals(6666, url.getParameter(TIMEOUT_KEY, 0));
             Assertions.assertEquals("random", url.getParameter(Constants.LOADBALANCE_KEY));
-            Assertions.assertEquals(url.getParameter(Constants.APPLICATION_KEY), "demo-consumer");
+            Assertions.assertEquals(url.getParameter(APPLICATION_KEY), "demo-consumer");
         }
     }
 
@@ -130,9 +135,9 @@ public class ConfigParserTest {
             URL url = urls.get(0);
             Assertions.assertEquals("127.0.0.1", url.getAddress());
             Assertions.assertEquals("*", url.getServiceInterface());
-            Assertions.assertEquals(6666, url.getParameter(Constants.TIMEOUT_KEY, 0));
+            Assertions.assertEquals(6666, url.getParameter(TIMEOUT_KEY, 0));
             Assertions.assertEquals("random", url.getParameter(Constants.LOADBALANCE_KEY));
-            Assertions.assertEquals(url.getParameter(Constants.APPLICATION_KEY), "demo-consumer");
+            Assertions.assertEquals(url.getParameter(APPLICATION_KEY), "demo-consumer");
         }
     }
 
@@ -145,9 +150,9 @@ public class ConfigParserTest {
             URL url = urls.get(0);
             Assertions.assertEquals("127.0.0.1", url.getAddress());
             Assertions.assertEquals("*", url.getServiceInterface());
-            Assertions.assertEquals(6666, url.getParameter(Constants.TIMEOUT_KEY, 0));
+            Assertions.assertEquals(6666, url.getParameter(TIMEOUT_KEY, 0));
             Assertions.assertEquals("random", url.getParameter(Constants.LOADBALANCE_KEY));
-            Assertions.assertEquals(url.getParameter(Constants.APPLICATION_KEY), "demo-consumer");
+            Assertions.assertEquals(url.getParameter(APPLICATION_KEY), "demo-consumer");
         }
     }
 
@@ -160,10 +165,10 @@ public class ConfigParserTest {
             URL url = urls.get(0);
             Assertions.assertEquals("127.0.0.1", url.getAddress());
             Assertions.assertEquals("*", url.getServiceInterface());
-            Assertions.assertEquals(6666, url.getParameter(Constants.TIMEOUT_KEY, 0));
+            Assertions.assertEquals(6666, url.getParameter(TIMEOUT_KEY, 0));
             Assertions.assertEquals("random", url.getParameter(Constants.LOADBALANCE_KEY));
             Assertions.assertEquals("127.0.0.1:20880", url.getParameter(Constants.OVERRIDE_PROVIDERS_KEY));
-            Assertions.assertEquals(url.getParameter(Constants.APPLICATION_KEY), "demo-consumer");
+            Assertions.assertEquals(url.getParameter(APPLICATION_KEY), "demo-consumer");
         }
     }
 

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/directory/MockDirInvocation.java

@@ -23,6 +23,11 @@ import org.apache.dubbo.rpc.Invoker;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * MockInvocation.java
  */
@@ -42,12 +47,12 @@ public class MockDirInvocation implements Invocation {
 
     public Map<String, String> getAttachments() {
         Map<String, String> attachments = new HashMap<String, String>();
-        attachments.put(Constants.PATH_KEY, "dubbo");
-        attachments.put(Constants.GROUP_KEY, "dubbo");
-        attachments.put(Constants.VERSION_KEY, "1.0.0");
+        attachments.put(PATH_KEY, "dubbo");
+        attachments.put(GROUP_KEY, "dubbo");
+        attachments.put(VERSION_KEY, "1.0.0");
         attachments.put(Constants.DUBBO_VERSION_KEY, "1.0.0");
         attachments.put(Constants.TOKEN_KEY, "sfag");
-        attachments.put(Constants.TIMEOUT_KEY, "1000");
+        attachments.put(TIMEOUT_KEY, "1000");
         return attachments;
     }
 
@@ -63,4 +68,4 @@ public class MockDirInvocation implements Invocation {
         return getAttachments().get(key);
     }
 
-}
+}

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/ClusterUtilsTest.java

@@ -18,11 +18,22 @@ package org.apache.dubbo.rpc.cluster.support;
 
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
-
 import org.apache.dubbo.common.URLBuilder;
+
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ALIVE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY_PREFIX;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PID_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADPOOL_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 public class ClusterUtilsTest {
 
     @Test
@@ -33,52 +44,52 @@ public class ClusterUtilsTest {
                 .setPassword("password");
 
         providerURL = URLBuilder.from(providerURL)
-                .addParameter(Constants.GROUP_KEY, "dubbo")
-                .addParameter(Constants.VERSION_KEY, "1.2.3")
+                .addParameter(GROUP_KEY, "dubbo")
+                .addParameter(VERSION_KEY, "1.2.3")
                 .addParameter(Constants.DUBBO_VERSION_KEY, "2.3.7")
-                .addParameter(Constants.THREADPOOL_KEY, "fixed")
-                .addParameter(Constants.THREADS_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.THREAD_NAME_KEY, "test")
-                .addParameter(Constants.CORE_THREADS_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.QUEUES_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.ALIVE_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.DEFAULT_KEY_PREFIX + Constants.THREADS_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.DEFAULT_KEY_PREFIX + Constants.THREADPOOL_KEY, "fixed")
-                .addParameter(Constants.DEFAULT_KEY_PREFIX + Constants.CORE_THREADS_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.DEFAULT_KEY_PREFIX + Constants.QUEUES_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.DEFAULT_KEY_PREFIX + Constants.ALIVE_KEY, Integer.MAX_VALUE)
-                .addParameter(Constants.DEFAULT_KEY_PREFIX + Constants.THREAD_NAME_KEY, "test")
+                .addParameter(THREADPOOL_KEY, "fixed")
+                .addParameter(THREADS_KEY, Integer.MAX_VALUE)
+                .addParameter(THREAD_NAME_KEY, "test")
+                .addParameter(CORE_THREADS_KEY, Integer.MAX_VALUE)
+                .addParameter(QUEUES_KEY, Integer.MAX_VALUE)
+                .addParameter(ALIVE_KEY, Integer.MAX_VALUE)
+                .addParameter(DEFAULT_KEY_PREFIX + THREADS_KEY, Integer.MAX_VALUE)
+                .addParameter(DEFAULT_KEY_PREFIX + THREADPOOL_KEY, "fixed")
+                .addParameter(DEFAULT_KEY_PREFIX + CORE_THREADS_KEY, Integer.MAX_VALUE)
+                .addParameter(DEFAULT_KEY_PREFIX + QUEUES_KEY, Integer.MAX_VALUE)
+                .addParameter(DEFAULT_KEY_PREFIX + ALIVE_KEY, Integer.MAX_VALUE)
+                .addParameter(DEFAULT_KEY_PREFIX + THREAD_NAME_KEY, "test")
                 .build();
 
         URL consumerURL = new URLBuilder(Constants.DUBBO_PROTOCOL, "localhost", 55555)
-                .addParameter(Constants.PID_KEY, "1234")
-                .addParameter(Constants.THREADPOOL_KEY, "foo")
+                .addParameter(PID_KEY, "1234")
+                .addParameter(THREADPOOL_KEY, "foo")
                 .build();
 
         URL url = ClusterUtils.mergeUrl(providerURL, consumerURL.getParameters());
 
-        Assertions.assertFalse(url.hasParameter(Constants.THREADS_KEY));
-        Assertions.assertFalse(url.hasParameter(Constants.DEFAULT_KEY_PREFIX + Constants.THREADS_KEY));
+        Assertions.assertFalse(url.hasParameter(THREADS_KEY));
+        Assertions.assertFalse(url.hasParameter(DEFAULT_KEY_PREFIX + THREADS_KEY));
 
-        Assertions.assertFalse(url.hasParameter(Constants.DEFAULT_KEY_PREFIX + Constants.THREADPOOL_KEY));
+        Assertions.assertFalse(url.hasParameter(DEFAULT_KEY_PREFIX + THREADPOOL_KEY));
 
-        Assertions.assertFalse(url.hasParameter(Constants.CORE_THREADS_KEY));
-        Assertions.assertFalse(url.hasParameter(Constants.DEFAULT_KEY_PREFIX + Constants.CORE_THREADS_KEY));
+        Assertions.assertFalse(url.hasParameter(CORE_THREADS_KEY));
+        Assertions.assertFalse(url.hasParameter(DEFAULT_KEY_PREFIX + CORE_THREADS_KEY));
 
-        Assertions.assertFalse(url.hasParameter(Constants.QUEUES_KEY));
-        Assertions.assertFalse(url.hasParameter(Constants.DEFAULT_KEY_PREFIX + Constants.QUEUES_KEY));
+        Assertions.assertFalse(url.hasParameter(QUEUES_KEY));
+        Assertions.assertFalse(url.hasParameter(DEFAULT_KEY_PREFIX + QUEUES_KEY));
 
-        Assertions.assertFalse(url.hasParameter(Constants.ALIVE_KEY));
-        Assertions.assertFalse(url.hasParameter(Constants.DEFAULT_KEY_PREFIX + Constants.ALIVE_KEY));
+        Assertions.assertFalse(url.hasParameter(ALIVE_KEY));
+        Assertions.assertFalse(url.hasParameter(DEFAULT_KEY_PREFIX + ALIVE_KEY));
 
-        Assertions.assertFalse(url.hasParameter(Constants.THREAD_NAME_KEY));
-        Assertions.assertFalse(url.hasParameter(Constants.DEFAULT_KEY_PREFIX + Constants.THREAD_NAME_KEY));
+        Assertions.assertFalse(url.hasParameter(THREAD_NAME_KEY));
+        Assertions.assertFalse(url.hasParameter(DEFAULT_KEY_PREFIX + THREAD_NAME_KEY));
 
         Assertions.assertEquals(url.getPath(), "path");
         Assertions.assertEquals(url.getUsername(), "username");
         Assertions.assertEquals(url.getPassword(), "password");
-        Assertions.assertEquals(url.getParameter(Constants.PID_KEY), "1234");
-        Assertions.assertEquals(url.getParameter(Constants.THREADPOOL_KEY), "foo");
+        Assertions.assertEquals(url.getParameter(PID_KEY), "1234");
+        Assertions.assertEquals(url.getParameter(THREADPOOL_KEY), "foo");
     }
 
 }

dubbo-cluster/src/test/java/org/apache/dubbo/rpc/cluster/support/MergeableClusterInvokerTest.java

@@ -38,6 +38,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
@@ -113,7 +114,7 @@ public class MergeableClusterInvokerTest {
 
             public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                 if ("getUrl".equals(method.getName())) {
-                    return url.addParameter(Constants.GROUP_KEY, "first");
+                    return url.addParameter(GROUP_KEY, "first");
                 }
                 if ("getInterface".equals(method.getName())) {
                     return MenuService.class;
@@ -129,7 +130,7 @@ public class MergeableClusterInvokerTest {
 
             public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                 if ("getUrl".equals(method.getName())) {
-                    return url.addParameter(Constants.GROUP_KEY, "second");
+                    return url.addParameter(GROUP_KEY, "second");
                 }
                 if ("getInterface".equals(method.getName())) {
                     return MenuService.class;
@@ -193,14 +194,14 @@ public class MergeableClusterInvokerTest {
         given(invocation.getInvoker()).willReturn(firstInvoker);
 
         given(firstInvoker.getUrl()).willReturn(
-                url.addParameter(Constants.GROUP_KEY, "first"));
+                url.addParameter(GROUP_KEY, "first"));
         given(firstInvoker.getInterface()).willReturn(MenuService.class);
         given(firstInvoker.invoke(invocation)).willReturn(new RpcResult())
                 ;
         given(firstInvoker.isAvailable()).willReturn(true);
 
         given(secondInvoker.getUrl()).willReturn(
-                url.addParameter(Constants.GROUP_KEY, "second"));
+                url.addParameter(GROUP_KEY, "second"));
         given(secondInvoker.getInterface()).willReturn(MenuService.class);
         given(secondInvoker.invoke(invocation)).willReturn(new RpcResult())
                 ;

dubbo-common/src/main/java/org/apache/dubbo/common/Constants.java

@@ -17,157 +17,14 @@
 
 package org.apache.dubbo.common;
 
-import org.apache.dubbo.common.constants.RemotingConstants;
-
 import java.util.concurrent.ExecutorService;
-import java.util.regex.Pattern;
+
+import static org.apache.dubbo.common.constants.CommonConstants.DUBBO;
 
 /**
  * Constants
  */
 public class Constants {
-
-    // BEGIN common
-    public static final String DUBBO = "dubbo";
-
-    public static final String PROVIDER = "provider";
-
-    public static final String CONSUMER = "consumer";
-
-    public static final String APPLICATION_KEY = "application";
-
-    public static final String REMOTE_APPLICATION_KEY = "remote.application";
-
-    public static final String ENABLED_KEY = "enabled";
-
-    public static final String DISABLED_KEY = "disabled";
-
-    public static final String DUBBO_PROPERTIES_KEY = "dubbo.properties.file";
-
-    public static final String DEFAULT_DUBBO_PROPERTIES = "dubbo.properties";
-
-    public static final String ANY_VALUE = "*";
-
-    public static final String COMMA_SEPARATOR = ",";
-
-    public static final Pattern COMMA_SPLIT_PATTERN = Pattern.compile("\\s*[,]+\\s*");
-
-    public final static String PATH_SEPARATOR = "/";
-
-    public final static String PROTOCOL_SEPARATOR = "://";
-
-    public static final String REGISTRY_SEPARATOR = "|";
-
-    public static final Pattern REGISTRY_SPLIT_PATTERN = Pattern.compile("\\s*[|;]+\\s*");
-
-    public static final String SEMICOLON_SEPARATOR = ";";
-
-    public static final Pattern SEMICOLON_SPLIT_PATTERN = Pattern.compile("\\s*[;]+\\s*");
-
-    public static final String DEFAULT_PROXY = "javassist";
-
-    public static final String DEFAULT_DIRECTORY = "dubbo";
-
-    public static final String PROTOCOL_KEY = "protocol";
-
-    public static final String DEFAULT_PROTOCOL = "dubbo";
-
-    public static final String DEFAULT_THREAD_NAME = "Dubbo";
-
-    public static final int DEFAULT_CORE_THREADS = 0;
-
-    public static final int DEFAULT_THREADS = 200;
-
-    public static final String THREADPOOL_KEY = "threadpool";
-
-    public static final String THREAD_NAME_KEY = "threadname";
-
-    public static final String CORE_THREADS_KEY = "corethreads";
-
-    public static final String THREADS_KEY = "threads";
-
-    public static final String QUEUES_KEY = "queues";
-
-    public static final String ALIVE_KEY = "alive";
-
-    public static final String DEFAULT_THREADPOOL = "limited";
-
-    public static final String DEFAULT_CLIENT_THREADPOOL = "cached";
-
-    public static final String IO_THREADS_KEY = "iothreads";
-
-    public static final int DEFAULT_QUEUES = 0;
-
-    public static final int DEFAULT_ALIVE = 60 * 1000;
-
-    public static final String TIMEOUT_KEY = "timeout";
-
-    public static final int DEFAULT_TIMEOUT = 1000;
-
-    public static final String REMOVE_VALUE_PREFIX = "-";
-
-    public static final String PROPERTIES_CHAR_SEPERATOR = "-";
-  
-    public static final String GROUP_CHAR_SEPERATOR = ":";
-
-    public static final String HIDE_KEY_PREFIX = ".";
-  
-    public static final String DEFAULT_KEY_PREFIX = "default.";
-
-    public static final String DEFAULT_KEY = "default";
-
-
-    /**
-     * Default timeout value in milliseconds for server shutdown
-     */
-    public static final int DEFAULT_SERVER_SHUTDOWN_TIMEOUT = 10000;
-
-    public static final String SIDE_KEY = "side";
-
-    public static final String PROVIDER_SIDE = "provider";
-
-    public static final String CONSUMER_SIDE = "consumer";
-
-    public static final String ANYHOST_KEY = "anyhost";
-
-    public static final String ANYHOST_VALUE = "0.0.0.0";
-
-    public static final String LOCALHOST_KEY = "localhost";
-
-    public static final String LOCALHOST_VALUE = "127.0.0.1";
-
-    public static final String METHODS_KEY = "methods";
-
-    public static final String METHOD_KEY = "method";
-
-    public static final String PID_KEY = "pid";
-
-    public static final String TIMESTAMP_KEY = "timestamp";
-
-    public static final String GROUP_KEY = "group";
-
-    public static final String PATH_KEY = "path";
-
-    public static final String INTERFACE_KEY = "interface";
-
-    public static final String FILE_KEY = "file";
-
-    public static final String DUMP_DIRECTORY = "dump.directory";
-
-    public static final String CLASSIFIER_KEY = "classifier";
-
-    public static final String VERSION_KEY = "version";
-
-    public static final String REVISION_KEY = "revision";
-
-    /**
-     * package version in the manifest
-     */
-    public static final String RELEASE_KEY = "release";
-
-    public static final int MAX_PROXY_COUNT = 65535;
-    // END common
-
     // BEGIN dubbo-remoting-api
     public static final String PAYLOAD_KEY = "payload";
     /**
@@ -791,10 +648,6 @@ public class Constants {
 
     public static final String COMPATIBLE_CONFIG_KEY = "compatible_config";
 
-    public static final String[] DEFAULT_REGISTER_PROVIDER_KEYS = {APPLICATION_KEY, RemotingConstants.CODEC_KEY, RemotingConstants.EXCHANGER_KEY, RemotingConstants.SERIALIZATION_KEY, CLUSTER_KEY, CONNECTIONS_KEY, DEPRECATED_KEY,
-            GROUP_KEY, LOADBALANCE_KEY, MOCK_KEY, PATH_KEY, TIMEOUT_KEY, TOKEN_KEY, VERSION_KEY, WARMUP_KEY, WEIGHT_KEY, TIMESTAMP_KEY, DUBBO_VERSION_KEY, RELEASE_KEY};
-
-    public static final String[] DEFAULT_REGISTER_CONSUMER_KEYS = {APPLICATION_KEY, VERSION_KEY, GROUP_KEY, DUBBO_VERSION_KEY, RELEASE_KEY};
 
     /**
      * To decide whether register center saves file synchronously, the default value is asynchronously

dubbo-common/src/main/java/org/apache/dubbo/common/Parameters.java

@@ -28,6 +28,9 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY_PREFIX;
+import static org.apache.dubbo.common.constants.CommonConstants.HIDE_KEY_PREFIX;
+
 /**
  * Parameters for backward compatibility for version prior to 2.0.5
  *
@@ -97,13 +100,13 @@ public class Parameters {
     public String getParameter(String key) {
         String value = parameters.get(key);
         if (StringUtils.isEmpty(value)) {
-            value = parameters.get(Constants.HIDE_KEY_PREFIX + key);
+            value = parameters.get(HIDE_KEY_PREFIX + key);
         }
         if (StringUtils.isEmpty(value)) {
-            value = parameters.get(Constants.DEFAULT_KEY_PREFIX + key);
+            value = parameters.get(DEFAULT_KEY_PREFIX + key);
         }
         if (StringUtils.isEmpty(value)) {
-            value = parameters.get(Constants.HIDE_KEY_PREFIX + Constants.DEFAULT_KEY_PREFIX + key);
+            value = parameters.get(HIDE_KEY_PREFIX + DEFAULT_KEY_PREFIX + key);
         }
         return value;
     }
@@ -171,7 +174,7 @@ public class Parameters {
     public String getMethodParameter(String method, String key) {
         String value = parameters.get(method + "." + key);
         if (StringUtils.isEmpty(value)) {
-            value = parameters.get(Constants.HIDE_KEY_PREFIX + method + "." + key);
+            value = parameters.get(HIDE_KEY_PREFIX + method + "." + key);
         }
         if (StringUtils.isEmpty(value)) {
             return getParameter(key);

dubbo-common/src/main/java/org/apache/dubbo/common/URL.java

@@ -40,6 +40,17 @@ import java.util.Map;
 import java.util.TreeMap;
 import java.util.concurrent.ConcurrentHashMap;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY_PREFIX;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * URL - Uniform Resource Locator (Immutable, ThreadSafe)
  * <p>
@@ -479,7 +490,7 @@ class URL implements Serializable {
     public String getParameter(String key) {
         String value = parameters.get(key);
         if (StringUtils.isEmpty(value)) {
-            value = parameters.get(Constants.DEFAULT_KEY_PREFIX + key);
+            value = parameters.get(DEFAULT_KEY_PREFIX + key);
         }
         return value;
     }
@@ -497,7 +508,7 @@ class URL implements Serializable {
         if (StringUtils.isEmpty(value)) {
             return defaultValue;
         }
-        return Constants.COMMA_SPLIT_PATTERN.split(value);
+        return COMMA_SPLIT_PATTERN.split(value);
     }
 
     public List<String> getParameter(String key, List<String> defaultValue) {
@@ -505,7 +516,7 @@ class URL implements Serializable {
         if (value == null || value.length() == 0) {
             return defaultValue;
         }
-        String[] strArray = Constants.COMMA_SPLIT_PATTERN.split(value);
+        String[] strArray = COMMA_SPLIT_PATTERN.split(value);
         return Arrays.asList(strArray);
     }
 
@@ -928,11 +939,11 @@ class URL implements Serializable {
     }
 
     public boolean isLocalHost() {
-        return NetUtils.isLocalHost(host) || getParameter(Constants.LOCALHOST_KEY, false);
+        return NetUtils.isLocalHost(host) || getParameter(LOCALHOST_KEY, false);
     }
 
     public boolean isAnyHost() {
-        return Constants.ANYHOST_VALUE.equals(host) || getParameter(Constants.ANYHOST_KEY, false);
+        return ANYHOST_VALUE.equals(host) || getParameter(ANYHOST_KEY, false);
     }
 
     public URL addParameterAndEncoded(String key, String value) {
@@ -1123,7 +1134,7 @@ class URL implements Serializable {
     }
 
     public String getRawParameter(String key) {
-        if (Constants.PROTOCOL_KEY.equals(key)) {
+        if (PROTOCOL_KEY.equals(key)) {
             return protocol;
         }
         if (Constants.USERNAME_KEY.equals(key)) {
@@ -1138,7 +1149,7 @@ class URL implements Serializable {
         if (Constants.PORT_KEY.equals(key)) {
             return String.valueOf(port);
         }
-        if (Constants.PATH_KEY.equals(key)) {
+        if (PATH_KEY.equals(key)) {
             return path;
         }
         return getParameter(key);
@@ -1147,7 +1158,7 @@ class URL implements Serializable {
     public Map<String, String> toMap() {
         Map<String, String> map = new HashMap<>(parameters);
         if (protocol != null) {
-            map.put(Constants.PROTOCOL_KEY, protocol);
+            map.put(PROTOCOL_KEY, protocol);
         }
         if (username != null) {
             map.put(Constants.USERNAME_KEY, username);
@@ -1162,7 +1173,7 @@ class URL implements Serializable {
             map.put(Constants.PORT_KEY, String.valueOf(port));
         }
         if (path != null) {
-            map.put(Constants.PATH_KEY, path);
+            map.put(PATH_KEY, path);
         }
         return map;
     }
@@ -1317,7 +1328,7 @@ class URL implements Serializable {
         if (inf == null) {
             return null;
         }
-        return buildKey(inf, getParameter(Constants.GROUP_KEY), getParameter(Constants.VERSION_KEY));
+        return buildKey(inf, getParameter(GROUP_KEY), getParameter(VERSION_KEY));
     }
 
     /**
@@ -1329,7 +1340,7 @@ class URL implements Serializable {
         if (inf == null) {
             return null;
         }
-        return buildKey(inf, getParameter(Constants.GROUP_KEY), getParameter(Constants.VERSION_KEY));
+        return buildKey(inf, getParameter(GROUP_KEY), getParameter(VERSION_KEY));
     }
 
     public static String buildKey(String path, String group, String version) {
@@ -1358,11 +1369,11 @@ class URL implements Serializable {
     }
 
     public String getServiceInterface() {
-        return getParameter(Constants.INTERFACE_KEY, path);
+        return getParameter(INTERFACE_KEY, path);
     }
 
     public URL setServiceInterface(String service) {
-        return addParameter(Constants.INTERFACE_KEY, service);
+        return addParameter(INTERFACE_KEY, service);
     }
 
     /**

dubbo-common/src/main/java/org/apache/dubbo/common/URLBuilder.java

@@ -24,6 +24,8 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY_PREFIX;
+
 public final class URLBuilder {
     private String protocol;
 
@@ -343,7 +345,7 @@ public final class URLBuilder {
     public String getParameter(String key) {
         String value = parameters.get(key);
         if (StringUtils.isEmpty(value)) {
-            value = parameters.get(Constants.DEFAULT_KEY_PREFIX + key);
+            value = parameters.get(DEFAULT_KEY_PREFIX + key);
         }
         return value;
     }

dubbo-common/src/main/java/org/apache/dubbo/common/bytecode/Proxy.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.bytecode;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.utils.ClassUtils;
 import org.apache.dubbo.common.utils.ReflectUtils;
 
@@ -34,6 +33,8 @@ import java.util.Set;
 import java.util.WeakHashMap;
 import java.util.concurrent.atomic.AtomicLong;
 
+import static org.apache.dubbo.common.constants.CommonConstants.MAX_PROXY_COUNT;
+
 /**
  * Proxy.
  */
@@ -73,7 +74,7 @@ public abstract class Proxy {
      * @return Proxy instance.
      */
     public static Proxy getProxy(ClassLoader cl, Class<?>... ics) {
-        if (ics.length > Constants.MAX_PROXY_COUNT) {
+        if (ics.length > MAX_PROXY_COUNT) {
             throw new IllegalArgumentException("interface limit exceeded");
         }
 

dubbo-common/src/main/java/org/apache/dubbo/common/config/ConfigurationUtils.java

@@ -27,6 +27,8 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Properties;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_SERVER_SHUTDOWN_TIMEOUT;
+
 /**
  * Utilities for manipulating configurations from different sources
  */
@@ -36,7 +38,7 @@ public class ConfigurationUtils {
     // FIXME
     @SuppressWarnings("deprecation")
     public static int getServerShutdownTimeout() {
-        int timeout = Constants.DEFAULT_SERVER_SHUTDOWN_TIMEOUT;
+        int timeout = DEFAULT_SERVER_SHUTDOWN_TIMEOUT;
         Configuration configuration = Environment.getInstance().getConfiguration();
         String value = StringUtils.trim(configuration.getString(Constants.SHUTDOWN_WAIT_KEY));
 

dubbo-common/src/main/java/org/apache/dubbo/common/config/Environment.java

@@ -16,7 +16,7 @@
  */
 package org.apache.dubbo.common.config;
 
-import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.utils.StringUtils;
 
 import java.util.HashMap;
@@ -141,7 +141,7 @@ public class Environment {
         if (sb.length() > 0) {
             return sb.toString();
         }
-        return Constants.DUBBO;
+        return CommonConstants.DUBBO;
     }
 
     public boolean isConfigCenterFirst() {

dubbo-common/src/main/java/org/apache/dubbo/common/constants/RegistryConstants.java

@@ -17,26 +17,6 @@
 
 package org.apache.dubbo.common.constants;
 
-import static org.apache.dubbo.common.Constants.APPLICATION_KEY;
-import static org.apache.dubbo.common.Constants.CLUSTER_KEY;
-import static org.apache.dubbo.common.constants.RemotingConstants.CODEC_KEY;
-import static org.apache.dubbo.common.Constants.CONNECTIONS_KEY;
-import static org.apache.dubbo.common.Constants.DEPRECATED_KEY;
-import static org.apache.dubbo.common.Constants.DUBBO_VERSION_KEY;
-import static org.apache.dubbo.common.constants.RemotingConstants.EXCHANGER_KEY;
-import static org.apache.dubbo.common.Constants.GROUP_KEY;
-import static org.apache.dubbo.common.Constants.LOADBALANCE_KEY;
-import static org.apache.dubbo.common.Constants.MOCK_KEY;
-import static org.apache.dubbo.common.Constants.PATH_KEY;
-import static org.apache.dubbo.common.Constants.RELEASE_KEY;
-import static org.apache.dubbo.common.constants.RemotingConstants.SERIALIZATION_KEY;
-import static org.apache.dubbo.common.Constants.TIMEOUT_KEY;
-import static org.apache.dubbo.common.Constants.TIMESTAMP_KEY;
-import static org.apache.dubbo.common.Constants.TOKEN_KEY;
-import static org.apache.dubbo.common.Constants.VERSION_KEY;
-import static org.apache.dubbo.common.Constants.WARMUP_KEY;
-import static org.apache.dubbo.common.Constants.WEIGHT_KEY;
-
 public interface RegistryConstants {
     String REGISTER_KEY = "register";
 
@@ -114,11 +94,6 @@ public interface RegistryConstants {
 
     String COMPATIBLE_CONFIG_KEY = "compatible_config";
 
-    String[] DEFAULT_REGISTER_PROVIDER_KEYS = {APPLICATION_KEY, CODEC_KEY, EXCHANGER_KEY, SERIALIZATION_KEY, CLUSTER_KEY, CONNECTIONS_KEY, DEPRECATED_KEY,
-            GROUP_KEY, LOADBALANCE_KEY, MOCK_KEY, PATH_KEY, TIMEOUT_KEY, TOKEN_KEY, VERSION_KEY, WARMUP_KEY, WEIGHT_KEY, TIMESTAMP_KEY, DUBBO_VERSION_KEY, RELEASE_KEY};
-
-    String[] DEFAULT_REGISTER_CONSUMER_KEYS = {APPLICATION_KEY, VERSION_KEY, GROUP_KEY, DUBBO_VERSION_KEY, RELEASE_KEY};
-
     /**
      * To decide whether register center saves file synchronously, the default value is asynchronously
      */

dubbo-common/src/main/java/org/apache/dubbo/common/extension/ExtensionLoader.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.extension;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.support.ActivateComparator;
 import org.apache.dubbo.common.logger.Logger;
@@ -48,6 +47,10 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.regex.Pattern;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.REMOVE_VALUE_PREFIX;
+
 /**
  * Load dubbo extensions
  * <ul>
@@ -190,7 +193,7 @@ public class ExtensionLoader<T> {
      */
     public List<T> getActivateExtension(URL url, String key, String group) {
         String value = url.getParameter(key);
-        return getActivateExtension(url, StringUtils.isEmpty(value) ? null : Constants.COMMA_SPLIT_PATTERN.split(value), group);
+        return getActivateExtension(url, StringUtils.isEmpty(value) ? null : COMMA_SPLIT_PATTERN.split(value), group);
     }
 
     /**
@@ -205,7 +208,7 @@ public class ExtensionLoader<T> {
     public List<T> getActivateExtension(URL url, String[] values, String group) {
         List<T> exts = new ArrayList<>();
         List<String> names = values == null ? new ArrayList<>(0) : Arrays.asList(values);
-        if (!names.contains(Constants.REMOVE_VALUE_PREFIX + Constants.DEFAULT_KEY)) {
+        if (!names.contains(REMOVE_VALUE_PREFIX + DEFAULT_KEY)) {
             getExtensionClasses();
             for (Map.Entry<String, Object> entry : cachedActivates.entrySet()) {
                 String name = entry.getKey();
@@ -225,7 +228,7 @@ public class ExtensionLoader<T> {
                 if (isMatchGroup(group, activateGroup)) {
                     T ext = getExtension(name);
                     if (!names.contains(name)
-                            && !names.contains(Constants.REMOVE_VALUE_PREFIX + name)
+                            && !names.contains(REMOVE_VALUE_PREFIX + name)
                             && isActive(activateValue, url)) {
                         exts.add(ext);
                     }
@@ -236,9 +239,9 @@ public class ExtensionLoader<T> {
         List<T> usrs = new ArrayList<>();
         for (int i = 0; i < names.size(); i++) {
             String name = names.get(i);
-            if (!name.startsWith(Constants.REMOVE_VALUE_PREFIX)
-                    && !names.contains(Constants.REMOVE_VALUE_PREFIX + name)) {
-                if (Constants.DEFAULT_KEY.equals(name)) {
+            if (!name.startsWith(REMOVE_VALUE_PREFIX)
+                    && !names.contains(REMOVE_VALUE_PREFIX + name)) {
+                if (DEFAULT_KEY.equals(name)) {
                     if (!usrs.isEmpty()) {
                         exts.addAll(0, usrs);
                         usrs.clear();

dubbo-common/src/main/java/org/apache/dubbo/common/threadpool/ThreadPool.java

@@ -16,13 +16,14 @@
  */
 package org.apache.dubbo.common.threadpool;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.Adaptive;
 import org.apache.dubbo.common.extension.SPI;
 
 import java.util.concurrent.Executor;
 
+import static org.apache.dubbo.common.constants.CommonConstants.THREADPOOL_KEY;
+
 /**
  * ThreadPool
  */
@@ -35,7 +36,7 @@ public interface ThreadPool {
      * @param url URL contains thread parameter
      * @return thread pool
      */
-    @Adaptive({Constants.THREADPOOL_KEY})
+    @Adaptive({THREADPOOL_KEY})
     Executor getExecutor(URL url);
 
-}
+}

dubbo-common/src/main/java/org/apache/dubbo/common/threadpool/support/AbortPolicyWithReport.java

@@ -26,12 +26,13 @@ import java.util.concurrent.RejectedExecutionException;
 import java.util.concurrent.Semaphore;
 import java.util.concurrent.ThreadPoolExecutor;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.JVMUtil;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DUMP_DIRECTORY;
+
 /**
  * Abort Policy.
  * Log warn info when abort.
@@ -92,7 +93,7 @@ public class AbortPolicyWithReport extends ThreadPoolExecutor.AbortPolicy {
 
         ExecutorService pool = Executors.newSingleThreadExecutor();
         pool.execute(() -> {
-            String dumpPath = url.getParameter(Constants.DUMP_DIRECTORY, System.getProperty("user.home"));
+            String dumpPath = url.getParameter(DUMP_DIRECTORY, System.getProperty("user.home"));
 
             SimpleDateFormat sdf;
 

dubbo-common/src/main/java/org/apache/dubbo/common/threadpool/support/cached/CachedThreadPool.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.threadpool.support.cached;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.NamedInternalThreadFactory;
 import org.apache.dubbo.common.threadpool.ThreadPool;
@@ -28,6 +27,16 @@ import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ALIVE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_ALIVE;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_CORE_THREADS;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_QUEUES;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_THREAD_NAME;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+
 /**
  * This thread pool is self-tuned. Thread will be recycled after idle for one minute, and new thread will be created for
  * the upcoming request.
@@ -38,11 +47,11 @@ public class CachedThreadPool implements ThreadPool {
 
     @Override
     public Executor getExecutor(URL url) {
-        String name = url.getParameter(Constants.THREAD_NAME_KEY, Constants.DEFAULT_THREAD_NAME);
-        int cores = url.getParameter(Constants.CORE_THREADS_KEY, Constants.DEFAULT_CORE_THREADS);
-        int threads = url.getParameter(Constants.THREADS_KEY, Integer.MAX_VALUE);
-        int queues = url.getParameter(Constants.QUEUES_KEY, Constants.DEFAULT_QUEUES);
-        int alive = url.getParameter(Constants.ALIVE_KEY, Constants.DEFAULT_ALIVE);
+        String name = url.getParameter(THREAD_NAME_KEY, DEFAULT_THREAD_NAME);
+        int cores = url.getParameter(CORE_THREADS_KEY, DEFAULT_CORE_THREADS);
+        int threads = url.getParameter(THREADS_KEY, Integer.MAX_VALUE);
+        int queues = url.getParameter(QUEUES_KEY, DEFAULT_QUEUES);
+        int alive = url.getParameter(ALIVE_KEY, DEFAULT_ALIVE);
         return new ThreadPoolExecutor(cores, threads, alive, TimeUnit.MILLISECONDS,
                 queues == 0 ? new SynchronousQueue<Runnable>() :
                         (queues < 0 ? new LinkedBlockingQueue<Runnable>()

dubbo-common/src/main/java/org/apache/dubbo/common/threadpool/support/eager/EagerThreadPool.java

@@ -17,7 +17,6 @@
 
 package org.apache.dubbo.common.threadpool.support.eager;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.NamedInternalThreadFactory;
 import org.apache.dubbo.common.threadpool.ThreadPool;
@@ -26,6 +25,16 @@ import org.apache.dubbo.common.threadpool.support.AbortPolicyWithReport;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ALIVE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_ALIVE;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_CORE_THREADS;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_QUEUES;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_THREAD_NAME;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+
 /**
  * EagerThreadPool
  * When the core threads are all in busy,
@@ -35,11 +44,11 @@ public class EagerThreadPool implements ThreadPool {
 
     @Override
     public Executor getExecutor(URL url) {
-        String name = url.getParameter(Constants.THREAD_NAME_KEY, Constants.DEFAULT_THREAD_NAME);
-        int cores = url.getParameter(Constants.CORE_THREADS_KEY, Constants.DEFAULT_CORE_THREADS);
-        int threads = url.getParameter(Constants.THREADS_KEY, Integer.MAX_VALUE);
-        int queues = url.getParameter(Constants.QUEUES_KEY, Constants.DEFAULT_QUEUES);
-        int alive = url.getParameter(Constants.ALIVE_KEY, Constants.DEFAULT_ALIVE);
+        String name = url.getParameter(THREAD_NAME_KEY, DEFAULT_THREAD_NAME);
+        int cores = url.getParameter(CORE_THREADS_KEY, DEFAULT_CORE_THREADS);
+        int threads = url.getParameter(THREADS_KEY, Integer.MAX_VALUE);
+        int queues = url.getParameter(QUEUES_KEY, DEFAULT_QUEUES);
+        int alive = url.getParameter(ALIVE_KEY, DEFAULT_ALIVE);
 
         // init queue and executor
         TaskQueue<Runnable> taskQueue = new TaskQueue<Runnable>(queues <= 0 ? 1 : queues);

dubbo-common/src/main/java/org/apache/dubbo/common/threadpool/support/fixed/FixedThreadPool.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.threadpool.support.fixed;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.NamedInternalThreadFactory;
 import org.apache.dubbo.common.threadpool.ThreadPool;
@@ -28,6 +27,13 @@ import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_QUEUES;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_THREADS;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_THREAD_NAME;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+
 /**
  * Creates a thread pool that reuses a fixed number of threads
  *
@@ -37,9 +43,9 @@ public class FixedThreadPool implements ThreadPool {
 
     @Override
     public Executor getExecutor(URL url) {
-        String name = url.getParameter(Constants.THREAD_NAME_KEY, Constants.DEFAULT_THREAD_NAME);
-        int threads = url.getParameter(Constants.THREADS_KEY, Constants.DEFAULT_THREADS);
-        int queues = url.getParameter(Constants.QUEUES_KEY, Constants.DEFAULT_QUEUES);
+        String name = url.getParameter(THREAD_NAME_KEY, DEFAULT_THREAD_NAME);
+        int threads = url.getParameter(THREADS_KEY, DEFAULT_THREADS);
+        int queues = url.getParameter(QUEUES_KEY, DEFAULT_QUEUES);
         return new ThreadPoolExecutor(threads, threads, 0, TimeUnit.MILLISECONDS,
                 queues == 0 ? new SynchronousQueue<Runnable>() :
                         (queues < 0 ? new LinkedBlockingQueue<Runnable>()

dubbo-common/src/main/java/org/apache/dubbo/common/threadpool/support/limited/LimitedThreadPool.java

@@ -17,7 +17,6 @@
 
 package org.apache.dubbo.common.threadpool.support.limited;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.NamedInternalThreadFactory;
 import org.apache.dubbo.common.threadpool.ThreadPool;
@@ -29,6 +28,15 @@ import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_CORE_THREADS;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_QUEUES;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_THREADS;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_THREAD_NAME;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+
 /**
  * Creates a thread pool that creates new threads as needed until limits reaches. This thread pool will not shrink
  * automatically.
@@ -37,10 +45,10 @@ public class LimitedThreadPool implements ThreadPool {
 
     @Override
     public Executor getExecutor(URL url) {
-        String name = url.getParameter(Constants.THREAD_NAME_KEY, Constants.DEFAULT_THREAD_NAME);
-        int cores = url.getParameter(Constants.CORE_THREADS_KEY, Constants.DEFAULT_CORE_THREADS);
-        int threads = url.getParameter(Constants.THREADS_KEY, Constants.DEFAULT_THREADS);
-        int queues = url.getParameter(Constants.QUEUES_KEY, Constants.DEFAULT_QUEUES);
+        String name = url.getParameter(THREAD_NAME_KEY, DEFAULT_THREAD_NAME);
+        int cores = url.getParameter(CORE_THREADS_KEY, DEFAULT_CORE_THREADS);
+        int threads = url.getParameter(THREADS_KEY, DEFAULT_THREADS);
+        int queues = url.getParameter(QUEUES_KEY, DEFAULT_QUEUES);
         return new ThreadPoolExecutor(cores, threads, Long.MAX_VALUE, TimeUnit.MILLISECONDS,
                 queues == 0 ? new SynchronousQueue<Runnable>() :
                         (queues < 0 ? new LinkedBlockingQueue<Runnable>()

dubbo-common/src/main/java/org/apache/dubbo/common/utils/ConfigUtils.java

@@ -16,7 +16,7 @@
  */
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.extension.ExtensionLoader;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -34,6 +34,10 @@ import java.util.Properties;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.REMOVE_VALUE_PREFIX;
+
 public class ConfigUtils {
 
     private static final Logger logger = LoggerFactory.getLogger(ConfigUtils.class);
@@ -88,7 +92,7 @@ public class ConfigUtils {
         List<String> names = new ArrayList<String>();
 
         // add initial values
-        String[] configs = (cfg == null || cfg.trim().length() == 0) ? new String[0] : Constants.COMMA_SPLIT_PATTERN.split(cfg);
+        String[] configs = (cfg == null || cfg.trim().length() == 0) ? new String[0] : COMMA_SPLIT_PATTERN.split(cfg);
         for (String config : configs) {
             if (config != null && config.trim().length() > 0) {
                 names.add(config);
@@ -96,22 +100,22 @@ public class ConfigUtils {
         }
 
         // -default is not included
-        if (!names.contains(Constants.REMOVE_VALUE_PREFIX + Constants.DEFAULT_KEY)) {
+        if (!names.contains(REMOVE_VALUE_PREFIX + DEFAULT_KEY)) {
             // add default extension
-            int i = names.indexOf(Constants.DEFAULT_KEY);
+            int i = names.indexOf(DEFAULT_KEY);
             if (i > 0) {
                 names.addAll(i, defaults);
             } else {
                 names.addAll(0, defaults);
             }
-            names.remove(Constants.DEFAULT_KEY);
+            names.remove(DEFAULT_KEY);
         } else {
-            names.remove(Constants.DEFAULT_KEY);
+            names.remove(DEFAULT_KEY);
         }
 
         // merge - configuration
         for (String name : new ArrayList<String>(names)) {
-            if (name.startsWith(Constants.REMOVE_VALUE_PREFIX)) {
+            if (name.startsWith(REMOVE_VALUE_PREFIX)) {
                 names.remove(name);
                 names.remove(name.substring(1));
             }
@@ -144,11 +148,11 @@ public class ConfigUtils {
         if (PROPERTIES == null) {
             synchronized (ConfigUtils.class) {
                 if (PROPERTIES == null) {
-                    String path = System.getProperty(Constants.DUBBO_PROPERTIES_KEY);
+                    String path = System.getProperty(CommonConstants.DUBBO_PROPERTIES_KEY);
                     if (path == null || path.length() == 0) {
-                        path = System.getenv(Constants.DUBBO_PROPERTIES_KEY);
+                        path = System.getenv(CommonConstants.DUBBO_PROPERTIES_KEY);
                         if (path == null || path.length() == 0) {
-                            path = Constants.DEFAULT_DUBBO_PROPERTIES;
+                            path = CommonConstants.DEFAULT_DUBBO_PROPERTIES;
                         }
                     }
                     PROPERTIES = ConfigUtils.loadProperties(path, false, true);

dubbo-common/src/main/java/org/apache/dubbo/common/utils/ExecutorUtil.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -24,9 +23,11 @@ import org.apache.dubbo.common.logger.LoggerFactory;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
-import java.util.concurrent.ScheduledFuture;
+
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
 
 public class ExecutorUtil {
     private static final Logger logger = LoggerFactory.getLogger(ExecutorUtil.class);
@@ -128,9 +129,9 @@ public class ExecutorUtil {
      * @return new url with updated thread name
      */
     public static URL setThreadName(URL url, String defaultName) {
-        String name = url.getParameter(Constants.THREAD_NAME_KEY, defaultName);
+        String name = url.getParameter(THREAD_NAME_KEY, defaultName);
         name = name + "-" + url.getAddress();
-        url = url.addParameter(Constants.THREAD_NAME_KEY, name);
+        url = url.addParameter(THREAD_NAME_KEY, name);
         return url;
     }
 

dubbo-common/src/main/java/org/apache/dubbo/common/utils/NetUtils.java

@@ -37,6 +37,10 @@ import java.util.Optional;
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.regex.Pattern;
 
+import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_KEY;
+
 /**
  * IP and Port Helper for RPC
  */
@@ -99,18 +103,18 @@ public class NetUtils {
     public static boolean isLocalHost(String host) {
         return host != null
                 && (LOCAL_IP_PATTERN.matcher(host).matches()
-                || host.equalsIgnoreCase(Constants.LOCALHOST_KEY));
+                || host.equalsIgnoreCase(LOCALHOST_KEY));
     }
 
     public static boolean isAnyHost(String host) {
-        return Constants.ANYHOST_VALUE.equals(host);
+        return ANYHOST_VALUE.equals(host);
     }
 
     public static boolean isInvalidLocalHost(String host) {
         return host == null
                 || host.length() == 0
-                || host.equalsIgnoreCase(Constants.LOCALHOST_KEY)
-                || host.equals(Constants.ANYHOST_VALUE)
+                || host.equalsIgnoreCase(LOCALHOST_KEY)
+                || host.equals(ANYHOST_VALUE)
                 || (LOCAL_IP_PATTERN.matcher(host).matches());
     }
 
@@ -130,8 +134,8 @@ public class NetUtils {
         String name = address.getHostAddress();
         boolean result = (name != null
                 && IP_PATTERN.matcher(name).matches()
-                && !Constants.ANYHOST_VALUE.equals(name)
-                && !Constants.LOCALHOST_VALUE.equals(name));
+                && !ANYHOST_VALUE.equals(name)
+                && !LOCALHOST_VALUE.equals(name));
         return result;
     }
 
@@ -178,7 +182,7 @@ public class NetUtils {
 
     public static String getLocalHost() {
         InetAddress address = getLocalAddress();
-        return address == null ? Constants.LOCALHOST_VALUE : address.getHostAddress();
+        return address == null ? LOCALHOST_VALUE : address.getHostAddress();
     }
 
     public static String filterLocalHost(String host) {

dubbo-common/src/main/java/org/apache/dubbo/common/utils/StringUtils.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.io.UnsafeStringWriter;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -33,6 +32,12 @@ import java.util.TreeMap;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * StringUtils
  */
@@ -458,7 +463,7 @@ public final class StringUtils {
     }
 
     public static boolean isContains(String values, String value) {
-        return isNotEmpty(values) && isContains(Constants.COMMA_SPLIT_PATTERN.split(values), value);
+        return isNotEmpty(values) && isContains(COMMA_SPLIT_PATTERN.split(values), value);
     }
 
     /**
@@ -714,12 +719,12 @@ public final class StringUtils {
 
     public static String getServiceKey(Map<String, String> ps) {
         StringBuilder buf = new StringBuilder();
-        String group = ps.get(Constants.GROUP_KEY);
+        String group = ps.get(GROUP_KEY);
         if (isNotEmpty(group)) {
             buf.append(group).append("/");
         }
-        buf.append(ps.get(Constants.INTERFACE_KEY));
-        String version = ps.get(Constants.VERSION_KEY);
+        buf.append(ps.get(INTERFACE_KEY));
+        String version = ps.get(VERSION_KEY);
         if (isNotEmpty(group)) {
             buf.append(":").append(version);
         }
@@ -774,7 +779,7 @@ public final class StringUtils {
         StringBuilder buf = new StringBuilder();
         for (Object arg : args) {
             if (buf.length() > 0) {
-                buf.append(Constants.COMMA_SEPARATOR);
+                buf.append(COMMA_SEPARATOR);
             }
             if (arg == null || ReflectUtils.isPrimitives(arg.getClass())) {
                 buf.append(arg);

dubbo-common/src/main/java/org/apache/dubbo/common/utils/UrlUtils.java

@@ -35,11 +35,22 @@ import static org.apache.dubbo.common.Constants.OVERRIDE_PROTOCOL;
 import static org.apache.dubbo.common.Constants.PROVIDERS_CATEGORY;
 import static org.apache.dubbo.common.Constants.ROUTERS_CATEGORY;
 import static org.apache.dubbo.common.Constants.ROUTE_PROTOCOL;
+import static org.apache.dubbo.common.constants.CommonConstants.ANY_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.CLASSIFIER_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.ENABLED_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.REGISTRY_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.REMOVE_VALUE_PREFIX;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
 
 public class UrlUtils {
 
     /**
-     *  in the url string,mark the param begin
+     * in the url string,mark the param begin
      */
     private final static String URL_PARAM_STARTING_SYMBOL = "?";
 
@@ -51,7 +62,7 @@ public class UrlUtils {
         if (address.contains("://") || address.contains(URL_PARAM_STARTING_SYMBOL)) {
             url = address;
         } else {
-            String[] addresses = Constants.COMMA_SPLIT_PATTERN.split(address);
+            String[] addresses = COMMA_SPLIT_PATTERN.split(address);
             url = addresses[0];
             if (addresses.length > 1) {
                 StringBuilder backup = new StringBuilder();
@@ -64,22 +75,22 @@ public class UrlUtils {
                 url += URL_PARAM_STARTING_SYMBOL + RemotingConstants.BACKUP_KEY + "=" + backup.toString();
             }
         }
-        String defaultProtocol = defaults == null ? null : defaults.get(Constants.PROTOCOL_KEY);
+        String defaultProtocol = defaults == null ? null : defaults.get(PROTOCOL_KEY);
         if (defaultProtocol == null || defaultProtocol.length() == 0) {
             defaultProtocol = Constants.DUBBO_PROTOCOL;
         }
         String defaultUsername = defaults == null ? null : defaults.get(Constants.USERNAME_KEY);
         String defaultPassword = defaults == null ? null : defaults.get(Constants.PASSWORD_KEY);
         int defaultPort = StringUtils.parseInteger(defaults == null ? null : defaults.get(Constants.PORT_KEY));
-        String defaultPath = defaults == null ? null : defaults.get(Constants.PATH_KEY);
+        String defaultPath = defaults == null ? null : defaults.get(PATH_KEY);
         Map<String, String> defaultParameters = defaults == null ? null : new HashMap<String, String>(defaults);
         if (defaultParameters != null) {
-            defaultParameters.remove(Constants.PROTOCOL_KEY);
+            defaultParameters.remove(PROTOCOL_KEY);
             defaultParameters.remove(Constants.USERNAME_KEY);
             defaultParameters.remove(Constants.PASSWORD_KEY);
             defaultParameters.remove(Constants.HOST_KEY);
             defaultParameters.remove(Constants.PORT_KEY);
-            defaultParameters.remove(Constants.PATH_KEY);
+            defaultParameters.remove(PATH_KEY);
         }
         URL u = URL.valueOf(url);
         boolean changed = false;
@@ -144,7 +155,7 @@ public class UrlUtils {
         if (address == null || address.length() == 0) {
             return null;
         }
-        String[] addresses = Constants.REGISTRY_SPLIT_PATTERN.split(address);
+        String[] addresses = REGISTRY_SPLIT_PATTERN.split(address);
         if (addresses == null || addresses.length == 0) {
             return null; //here won't be empty
         }
@@ -353,17 +364,17 @@ public class UrlUtils {
         }
         return URL.valueOf(Constants.EMPTY_PROTOCOL + "://0.0.0.0/" + service + URL_PARAM_STARTING_SYMBOL
                 + CATEGORY_KEY + "=" + category
-                + (group == null ? "" : "&" + Constants.GROUP_KEY + "=" + group)
-                + (version == null ? "" : "&" + Constants.VERSION_KEY + "=" + version));
+                + (group == null ? "" : "&" + GROUP_KEY + "=" + group)
+                + (version == null ? "" : "&" + VERSION_KEY + "=" + version));
     }
 
     public static boolean isMatchCategory(String category, String categories) {
         if (categories == null || categories.length() == 0) {
             return DEFAULT_CATEGORY.equals(category);
-        } else if (categories.contains(Constants.ANY_VALUE)) {
+        } else if (categories.contains(ANY_VALUE)) {
             return true;
-        } else if (categories.contains(Constants.REMOVE_VALUE_PREFIX)) {
-            return !categories.contains(Constants.REMOVE_VALUE_PREFIX + category);
+        } else if (categories.contains(REMOVE_VALUE_PREFIX)) {
+            return !categories.contains(REMOVE_VALUE_PREFIX + category);
         } else {
             return categories.contains(category);
         }
@@ -373,8 +384,8 @@ public class UrlUtils {
         String consumerInterface = consumerUrl.getServiceInterface();
         String providerInterface = providerUrl.getServiceInterface();
         //FIXME accept providerUrl with '*' as interface name, after carefully thought about all possible scenarios I think it's ok to add this condition.
-        if (!(Constants.ANY_VALUE.equals(consumerInterface)
-                || Constants.ANY_VALUE.equals(providerInterface)
+        if (!(ANY_VALUE.equals(consumerInterface)
+                || ANY_VALUE.equals(providerInterface)
                 || StringUtils.isEquals(consumerInterface, providerInterface))) {
             return false;
         }
@@ -383,21 +394,21 @@ public class UrlUtils {
                 consumerUrl.getParameter(CATEGORY_KEY, DEFAULT_CATEGORY))) {
             return false;
         }
-        if (!providerUrl.getParameter(Constants.ENABLED_KEY, true)
-                && !Constants.ANY_VALUE.equals(consumerUrl.getParameter(Constants.ENABLED_KEY))) {
+        if (!providerUrl.getParameter(ENABLED_KEY, true)
+                && !ANY_VALUE.equals(consumerUrl.getParameter(ENABLED_KEY))) {
             return false;
         }
 
-        String consumerGroup = consumerUrl.getParameter(Constants.GROUP_KEY);
-        String consumerVersion = consumerUrl.getParameter(Constants.VERSION_KEY);
-        String consumerClassifier = consumerUrl.getParameter(Constants.CLASSIFIER_KEY, Constants.ANY_VALUE);
+        String consumerGroup = consumerUrl.getParameter(GROUP_KEY);
+        String consumerVersion = consumerUrl.getParameter(VERSION_KEY);
+        String consumerClassifier = consumerUrl.getParameter(CLASSIFIER_KEY, ANY_VALUE);
 
-        String providerGroup = providerUrl.getParameter(Constants.GROUP_KEY);
-        String providerVersion = providerUrl.getParameter(Constants.VERSION_KEY);
-        String providerClassifier = providerUrl.getParameter(Constants.CLASSIFIER_KEY, Constants.ANY_VALUE);
-        return (Constants.ANY_VALUE.equals(consumerGroup) || StringUtils.isEquals(consumerGroup, providerGroup) || StringUtils.isContains(consumerGroup, providerGroup))
-                && (Constants.ANY_VALUE.equals(consumerVersion) || StringUtils.isEquals(consumerVersion, providerVersion))
-                && (consumerClassifier == null || Constants.ANY_VALUE.equals(consumerClassifier) || StringUtils.isEquals(consumerClassifier, providerClassifier));
+        String providerGroup = providerUrl.getParameter(GROUP_KEY);
+        String providerVersion = providerUrl.getParameter(VERSION_KEY);
+        String providerClassifier = providerUrl.getParameter(CLASSIFIER_KEY, ANY_VALUE);
+        return (ANY_VALUE.equals(consumerGroup) || StringUtils.isEquals(consumerGroup, providerGroup) || StringUtils.isContains(consumerGroup, providerGroup))
+                && (ANY_VALUE.equals(consumerVersion) || StringUtils.isEquals(consumerVersion, providerVersion))
+                && (consumerClassifier == null || ANY_VALUE.equals(consumerClassifier) || StringUtils.isEquals(consumerClassifier, providerClassifier));
     }
 
     public static boolean isMatchGlobPattern(String pattern, String value, URL param) {
@@ -440,12 +451,12 @@ public class UrlUtils {
     }
 
     public static boolean isServiceKeyMatch(URL pattern, URL value) {
-        return pattern.getParameter(Constants.INTERFACE_KEY).equals(
-                value.getParameter(Constants.INTERFACE_KEY))
-                && isItemMatch(pattern.getParameter(Constants.GROUP_KEY),
-                value.getParameter(Constants.GROUP_KEY))
-                && isItemMatch(pattern.getParameter(Constants.VERSION_KEY),
-                value.getParameter(Constants.VERSION_KEY));
+        return pattern.getParameter(INTERFACE_KEY).equals(
+                value.getParameter(INTERFACE_KEY))
+                && isItemMatch(pattern.getParameter(GROUP_KEY),
+                value.getParameter(GROUP_KEY))
+                && isItemMatch(pattern.getParameter(VERSION_KEY),
+                value.getParameter(VERSION_KEY));
     }
 
     public static List<URL> classifyUrls(List<URL> urls, Predicate<URL> predicate) {

dubbo-common/src/test/java/org/apache/dubbo/common/extension/ExtensionLoaderTest.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.extension;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.extension.activate.ActivateExt1;
 import org.apache.dubbo.common.extension.activate.impl.ActivateExt1Impl1;
@@ -57,6 +56,7 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
 import static org.hamcrest.CoreMatchers.allOf;
 import static org.hamcrest.CoreMatchers.anyOf;
 import static org.hamcrest.CoreMatchers.instanceOf;
@@ -376,14 +376,14 @@ public class ExtensionLoaderTest {
         Assertions.assertTrue(list.get(0).getClass() == ActivateExt1Impl1.class);
 
         // test group
-        url = url.addParameter(Constants.GROUP_KEY, "group1");
+        url = url.addParameter(GROUP_KEY, "group1");
         list = ExtensionLoader.getExtensionLoader(ActivateExt1.class)
                 .getActivateExtension(url, new String[]{}, "group1");
         Assertions.assertEquals(1, list.size());
         Assertions.assertTrue(list.get(0).getClass() == GroupActivateExtImpl.class);
 
         // test old @Activate group
-        url = url.addParameter(Constants.GROUP_KEY, "old_group");
+        url = url.addParameter(GROUP_KEY, "old_group");
         list = ExtensionLoader.getExtensionLoader(ActivateExt1.class)
                 .getActivateExtension(url, new String[]{}, "old_group");
         Assertions.assertEquals(2, list.size());
@@ -391,8 +391,8 @@ public class ExtensionLoaderTest {
                 || list.get(0).getClass() == OldActivateExt1Impl3.class);
 
         // test value
-        url = url.removeParameter(Constants.GROUP_KEY);
-        url = url.addParameter(Constants.GROUP_KEY, "value");
+        url = url.removeParameter(GROUP_KEY);
+        url = url.addParameter(GROUP_KEY, "value");
         url = url.addParameter("value", "value");
         list = ExtensionLoader.getExtensionLoader(ActivateExt1.class)
                 .getActivateExtension(url, new String[]{}, "value");
@@ -401,7 +401,7 @@ public class ExtensionLoaderTest {
 
         // test order
         url = URL.valueOf("test://localhost/test");
-        url = url.addParameter(Constants.GROUP_KEY, "order");
+        url = url.addParameter(GROUP_KEY, "order");
         list = ExtensionLoader.getExtensionLoader(ActivateExt1.class)
                 .getActivateExtension(url, new String[]{}, "order");
         Assertions.assertEquals(2, list.size());

dubbo-common/src/test/java/org/apache/dubbo/common/threadpool/support/cached/CachedThreadPoolTest.java

@@ -17,11 +17,11 @@
 
 package org.apache.dubbo.common.threadpool.support.cached;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.InternalThread;
 import org.apache.dubbo.common.threadpool.ThreadPool;
 import org.apache.dubbo.common.threadpool.support.AbortPolicyWithReport;
+
 import org.hamcrest.Matchers;
 import org.junit.jupiter.api.Test;
 
@@ -31,22 +31,26 @@ import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ALIVE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.startsWith;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class CachedThreadPoolTest {
     @Test
     public void getExecutor1() throws Exception {
         URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" +
-                Constants.THREAD_NAME_KEY + "=demo&" +
-                Constants.CORE_THREADS_KEY + "=1&" +
-                Constants.THREADS_KEY + "=2&" +
-                Constants.ALIVE_KEY + "=1000&" +
-                Constants.QUEUES_KEY + "=0");
+                THREAD_NAME_KEY + "=demo&" +
+                CORE_THREADS_KEY + "=1&" +
+                THREADS_KEY + "=2&" +
+                ALIVE_KEY + "=1000&" +
+                QUEUES_KEY + "=0");
         ThreadPool threadPool = new CachedThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getCorePoolSize(), is(1));
@@ -72,7 +76,7 @@ public class CachedThreadPoolTest {
 
     @Test
     public void getExecutor2() throws Exception {
-        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + Constants.QUEUES_KEY + "=1");
+        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + QUEUES_KEY + "=1");
         ThreadPool threadPool = new CachedThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getQueue(), Matchers.<BlockingQueue<Runnable>>instanceOf(LinkedBlockingQueue.class));

dubbo-common/src/test/java/org/apache/dubbo/common/threadpool/support/eager/EagerThreadPoolTest.java

@@ -17,11 +17,11 @@
 
 package org.apache.dubbo.common.threadpool.support.eager;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.InternalThread;
 import org.apache.dubbo.common.threadpool.ThreadPool;
 import org.apache.dubbo.common.threadpool.support.AbortPolicyWithReport;
+
 import org.hamcrest.Matchers;
 import org.junit.jupiter.api.Test;
 
@@ -31,20 +31,25 @@ import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ALIVE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.startsWith;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class EagerThreadPoolTest {
     @Test
     public void getExecutor1() throws Exception {
         URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" +
-                Constants.THREAD_NAME_KEY + "=demo&" +
-                Constants.CORE_THREADS_KEY + "=1&" +
-                Constants.THREADS_KEY + "=2&" +
-                Constants.ALIVE_KEY + "=1000&" +
-                Constants.QUEUES_KEY + "=0");
+                THREAD_NAME_KEY + "=demo&" +
+                CORE_THREADS_KEY + "=1&" +
+                THREADS_KEY + "=2&" +
+                ALIVE_KEY + "=1000&" +
+                QUEUES_KEY + "=0");
         ThreadPool threadPool = new EagerThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor, instanceOf(EagerThreadPoolExecutor.class));
@@ -73,7 +78,7 @@ public class EagerThreadPoolTest {
 
     @Test
     public void getExecutor2() throws Exception {
-        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + Constants.QUEUES_KEY + "=2");
+        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + QUEUES_KEY + "=2");
         ThreadPool threadPool = new EagerThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getQueue().remainingCapacity(), is(2));

dubbo-common/src/test/java/org/apache/dubbo/common/threadpool/support/fixed/FixedThreadPoolTest.java

@@ -17,12 +17,11 @@
 
 package org.apache.dubbo.common.threadpool.support.fixed;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.InternalThread;
 import org.apache.dubbo.common.threadpool.ThreadPool;
 import org.apache.dubbo.common.threadpool.support.AbortPolicyWithReport;
-import org.apache.dubbo.common.threadpool.support.limited.LimitedThreadPool;
+
 import org.hamcrest.Matchers;
 import org.junit.jupiter.api.Test;
 
@@ -34,19 +33,23 @@ import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.startsWith;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class FixedThreadPoolTest {
     @Test
     public void getExecutor1() throws Exception {
         URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" +
-                Constants.THREAD_NAME_KEY + "=demo&" +
-                Constants.CORE_THREADS_KEY + "=1&" +
-                Constants.THREADS_KEY + "=2&" +
-                Constants.QUEUES_KEY + "=0");
+                THREAD_NAME_KEY + "=demo&" +
+                CORE_THREADS_KEY + "=1&" +
+                THREADS_KEY + "=2&" +
+                QUEUES_KEY + "=0");
         ThreadPool threadPool = new FixedThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getCorePoolSize(), is(2));
@@ -73,7 +76,7 @@ public class FixedThreadPoolTest {
 
     @Test
     public void getExecutor2() throws Exception {
-        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + Constants.QUEUES_KEY + "=1");
+        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + QUEUES_KEY + "=1");
         ThreadPool threadPool = new FixedThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getQueue(), Matchers.<BlockingQueue<Runnable>>instanceOf(LinkedBlockingQueue.class));

dubbo-common/src/test/java/org/apache/dubbo/common/threadpool/support/limited/LimitedThreadPoolTest.java

@@ -17,11 +17,11 @@
 
 package org.apache.dubbo.common.threadpool.support.limited;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.threadlocal.InternalThread;
 import org.apache.dubbo.common.threadpool.ThreadPool;
 import org.apache.dubbo.common.threadpool.support.AbortPolicyWithReport;
+
 import org.hamcrest.Matchers;
 import org.junit.jupiter.api.Test;
 
@@ -31,21 +31,24 @@ import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.SynchronousQueue;
 import java.util.concurrent.ThreadPoolExecutor;
-import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.CORE_THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.QUEUES_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREADS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.startsWith;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class LimitedThreadPoolTest {
     @Test
     public void getExecutor1() throws Exception {
         URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" +
-                Constants.THREAD_NAME_KEY + "=demo&" +
-                Constants.CORE_THREADS_KEY + "=1&" +
-                Constants.THREADS_KEY + "=2&" +
-                Constants.QUEUES_KEY + "=0");
+                THREAD_NAME_KEY + "=demo&" +
+                CORE_THREADS_KEY + "=1&" +
+                THREADS_KEY + "=2&" +
+                QUEUES_KEY + "=0");
         ThreadPool threadPool = new LimitedThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getCorePoolSize(), is(1));
@@ -71,7 +74,7 @@ public class LimitedThreadPoolTest {
 
     @Test
     public void getExecutor2() throws Exception {
-        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + Constants.QUEUES_KEY + "=1");
+        URL url = URL.valueOf("dubbo://10.20.130.230:20880/context/path?" + QUEUES_KEY + "=1");
         ThreadPool threadPool = new LimitedThreadPool();
         ThreadPoolExecutor executor = (ThreadPoolExecutor) threadPool.getExecutor(url);
         assertThat(executor.getQueue(), Matchers.<BlockingQueue<Runnable>>instanceOf(LinkedBlockingQueue.class));

dubbo-common/src/test/java/org/apache/dubbo/common/utils/CIDRUtilsTest.java

@@ -21,9 +21,6 @@ import org.junit.jupiter.api.Test;
 
 import java.net.UnknownHostException;
 
-/**
- * @author cvictory ON 2019-02-28
- */
 public class CIDRUtilsTest {
 
     @Test

dubbo-common/src/test/java/org/apache/dubbo/common/utils/ConfigUtilsTest.java

@@ -16,8 +16,9 @@
  */
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.threadpool.ThreadPool;
+
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
@@ -29,12 +30,12 @@ import java.util.List;
 import java.util.Properties;
 
 import static java.util.Arrays.asList;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.greaterThan;
 import static org.hamcrest.Matchers.is;
 import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class ConfigUtilsTest {
     @BeforeEach
@@ -119,19 +120,19 @@ public class ConfigUtilsTest {
     @Test
     public void testGetProperties1() throws Exception {
         try {
-            System.setProperty(Constants.DUBBO_PROPERTIES_KEY, "properties.load");
+            System.setProperty(CommonConstants.DUBBO_PROPERTIES_KEY, "properties.load");
             Properties p = ConfigUtils.getProperties();
             assertThat((String) p.get("a"), equalTo("12"));
             assertThat((String) p.get("b"), equalTo("34"));
             assertThat((String) p.get("c"), equalTo("56"));
         } finally {
-            System.clearProperty(Constants.DUBBO_PROPERTIES_KEY);
+            System.clearProperty(CommonConstants.DUBBO_PROPERTIES_KEY);
         }
     }
 
     @Test
     public void testGetProperties2() throws Exception {
-        System.clearProperty(Constants.DUBBO_PROPERTIES_KEY);
+        System.clearProperty(CommonConstants.DUBBO_PROPERTIES_KEY);
         Properties p = ConfigUtils.getProperties();
         assertThat((String) p.get("dubbo"), equalTo("properties"));
     }
@@ -256,4 +257,4 @@ public class ConfigUtilsTest {
     public void testGetPid() throws Exception {
         assertThat(ConfigUtils.getPid(), greaterThan(0));
     }
-}
+}

dubbo-common/src/test/java/org/apache/dubbo/common/utils/ExecutorUtilTest.java

@@ -17,8 +17,8 @@
 
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
+
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
 
@@ -26,9 +26,10 @@ import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.THREAD_NAME_KEY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
-import static org.hamcrest.MatcherAssert.assertThat;
 import static org.mockito.Mockito.atLeast;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -76,8 +77,8 @@ public class ExecutorUtilTest {
 
     @Test
     public void testSetThreadName() throws Exception {
-        URL url = new URL("dubbo", "localhost", 1234).addParameter(Constants.THREAD_NAME_KEY, "custom-thread");
+        URL url = new URL("dubbo", "localhost", 1234).addParameter(THREAD_NAME_KEY, "custom-thread");
         url = ExecutorUtil.setThreadName(url, "default-name");
-        assertThat(url.getParameter(Constants.THREAD_NAME_KEY), equalTo("custom-thread-localhost:1234"));
+        assertThat(url.getParameter(THREAD_NAME_KEY), equalTo("custom-thread-localhost:1234"));
     }
 }

dubbo-common/src/test/java/org/apache/dubbo/common/utils/StringUtilsTest.java

@@ -16,8 +16,6 @@
  */
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
-
 import org.junit.jupiter.api.Test;
 
 import java.util.ArrayList;
@@ -26,6 +24,9 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
@@ -193,9 +194,9 @@ public class StringUtilsTest {
     @Test
     public void testGetServiceKey() throws Exception {
         Map<String, String> map = new HashMap<String, String>();
-        map.put(Constants.GROUP_KEY, "dubbo");
-        map.put(Constants.INTERFACE_KEY, "a.b.c.Foo");
-        map.put(Constants.VERSION_KEY, "1.0.0");
+        map.put(GROUP_KEY, "dubbo");
+        map.put(INTERFACE_KEY, "a.b.c.Foo");
+        map.put(VERSION_KEY, "1.0.0");
         assertThat(StringUtils.getServiceKey(map), equalTo("dubbo/a.b.c.Foo:1.0.0"));
     }
 
@@ -295,4 +296,4 @@ public class StringUtilsTest {
         assertEquals("bi-side blank", StringUtils.trim(" bi-side blank "));
 
     }
-}
+}

dubbo-common/src/test/java/org/apache/dubbo/common/utils/UrlUtilsTest.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.common.utils;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 
 import org.junit.jupiter.api.Test;
@@ -28,11 +27,14 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNull;
-import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class UrlUtilsTest {
@@ -331,16 +333,16 @@ public class UrlUtilsTest {
     @Test
     public void testIsServiceKeyMatch() throws Exception {
         URL url = URL.valueOf("test://127.0.0.1");
-        URL pattern = url.addParameter(Constants.GROUP_KEY, "test")
-                .addParameter(Constants.INTERFACE_KEY, "test")
-                .addParameter(Constants.VERSION_KEY, "test");
+        URL pattern = url.addParameter(GROUP_KEY, "test")
+                .addParameter(INTERFACE_KEY, "test")
+                .addParameter(VERSION_KEY, "test");
         URL value = pattern;
         assertTrue(UrlUtils.isServiceKeyMatch(pattern, value));
 
-        pattern = pattern.addParameter(Constants.GROUP_KEY, "*");
+        pattern = pattern.addParameter(GROUP_KEY, "*");
         assertTrue(UrlUtils.isServiceKeyMatch(pattern, value));
 
-        pattern = pattern.addParameter(Constants.VERSION_KEY, "*");
+        pattern = pattern.addParameter(VERSION_KEY, "*");
         assertTrue(UrlUtils.isServiceKeyMatch(pattern, value));
     }
 
@@ -361,4 +363,4 @@ public class UrlUtilsTest {
         assertTrue(UrlUtils.isMatchGlobPattern("v*e", "value"));
         assertTrue(UrlUtils.isMatchGlobPattern("$key", "value", URL.valueOf("dubbo://localhost:8080/Foo?key=v*e")));
     }
-}
+}

dubbo-compatible/src/main/java/com/alibaba/dubbo/cache/support/AbstractCacheFactory.java

@@ -19,13 +19,14 @@ package com.alibaba.dubbo.cache.support;
 
 import com.alibaba.dubbo.cache.Cache;
 import com.alibaba.dubbo.cache.CacheFactory;
-import com.alibaba.dubbo.common.Constants;
 import com.alibaba.dubbo.common.URL;
 import com.alibaba.dubbo.rpc.Invocation;
 
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 
+import static org.apache.dubbo.common.constants.CommonConstants.METHOD_KEY;
+
 @Deprecated
 public abstract class AbstractCacheFactory implements CacheFactory {
 
@@ -33,7 +34,7 @@ public abstract class AbstractCacheFactory implements CacheFactory {
 
     @Override
     public Cache getCache(URL url, Invocation invocation) {
-        url = url.addParameter(Constants.METHOD_KEY, invocation.getMethodName());
+        url = url.addParameter(METHOD_KEY, invocation.getMethodName());
         String key = url.toFullString();
         Cache cache = caches.get(key);
         if (cache == null) {

dubbo-compatible/src/test/java/org/apache/dubbo/config/ApplicationConfigTest.java

@@ -21,7 +21,6 @@ import com.alibaba.dubbo.common.Constants;
 import com.alibaba.dubbo.config.ApplicationConfig;
 import com.alibaba.dubbo.config.MonitorConfig;
 import com.alibaba.dubbo.config.RegistryConfig;
-
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
@@ -29,13 +28,15 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DUMP_DIRECTORY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.hasEntry;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.sameInstance;
 import static org.hamcrest.collection.IsCollectionWithSize.hasSize;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class ApplicationConfigTest {
     @Test
@@ -47,7 +48,7 @@ public class ApplicationConfigTest {
         assertThat(application.getName(), equalTo("app2"));
         Map<String, String> parameters = new HashMap<String, String>();
         ApplicationConfig.appendParameters(parameters, application);
-        assertThat(parameters, hasEntry(Constants.APPLICATION_KEY, "app2"));
+        assertThat(parameters, hasEntry(APPLICATION_KEY, "app2"));
     }
 
     @Test
@@ -141,7 +142,7 @@ public class ApplicationConfigTest {
         assertThat(application.getDumpDirectory(), equalTo("/dump"));
         Map<String, String> parameters = new HashMap<String, String>();
         ApplicationConfig.appendParameters(parameters, application);
-        assertThat(parameters, hasEntry(Constants.DUMP_DIRECTORY, "/dump"));
+        assertThat(parameters, hasEntry(DUMP_DIRECTORY, "/dump"));
     }
 
     @Test
@@ -181,4 +182,4 @@ public class ApplicationConfigTest {
         assertThat(parameters, hasEntry("k1", "v1"));
         assertThat(parameters, hasEntry(Constants.ACCEPT_FOREIGN_IP, "true"));
     }
-}
+}

dubbo-compatible/src/test/java/org/apache/dubbo/filter/LegacyInvocation.java

@@ -24,6 +24,12 @@ import com.alibaba.dubbo.rpc.Invoker;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.Constants.DUBBO_VERSION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * MockInvocation.java
  */
@@ -49,12 +55,12 @@ public class LegacyInvocation implements Invocation {
 
     public Map<String, String> getAttachments() {
         Map<String, String> attachments = new HashMap<String, String>();
-        attachments.put(Constants.PATH_KEY, "dubbo");
-        attachments.put(Constants.GROUP_KEY, "dubbo");
-        attachments.put(Constants.VERSION_KEY, "1.0.0");
-        attachments.put(Constants.DUBBO_VERSION_KEY, "1.0.0");
+        attachments.put(PATH_KEY, "dubbo");
+        attachments.put(GROUP_KEY, "dubbo");
+        attachments.put(VERSION_KEY, "1.0.0");
+        attachments.put(DUBBO_VERSION_KEY, "1.0.0");
         attachments.put(Constants.TOKEN_KEY, "sfag");
-        attachments.put(Constants.TIMEOUT_KEY, "1000");
+        attachments.put(TIMEOUT_KEY, "1000");
         return attachments;
     }
 
@@ -70,4 +76,4 @@ public class LegacyInvocation implements Invocation {
         return getAttachments().get(key);
     }
 
-}
+}

dubbo-compatible/src/test/java/org/apache/dubbo/service/MockInvocation.java

@@ -23,6 +23,11 @@ import org.apache.dubbo.rpc.Invoker;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * MockInvocation.java
  */
@@ -48,12 +53,12 @@ public class MockInvocation implements Invocation {
 
     public Map<String, String> getAttachments() {
         Map<String, String> attachments = new HashMap<String, String>();
-        attachments.put(Constants.PATH_KEY, "dubbo");
-        attachments.put(Constants.GROUP_KEY, "dubbo");
-        attachments.put(Constants.VERSION_KEY, "1.0.0");
+        attachments.put(PATH_KEY, "dubbo");
+        attachments.put(GROUP_KEY, "dubbo");
+        attachments.put(VERSION_KEY, "1.0.0");
         attachments.put(Constants.DUBBO_VERSION_KEY, "1.0.0");
         attachments.put(Constants.TOKEN_KEY, "sfag");
-        attachments.put(Constants.TIMEOUT_KEY, "1000");
+        attachments.put(TIMEOUT_KEY, "1000");
         return attachments;
     }
 
@@ -69,4 +74,4 @@ public class MockInvocation implements Invocation {
         return getAttachments().get(key);
     }
 
-}
+}

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/AbstractConfig.java

@@ -16,11 +16,11 @@
  */
 package org.apache.dubbo.config;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.config.CompositeConfiguration;
 import org.apache.dubbo.common.config.Environment;
 import org.apache.dubbo.common.config.InmemoryConfiguration;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.extension.ExtensionLoader;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -42,6 +42,9 @@ import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.REMOVE_VALUE_PREFIX;
+
 /**
  * Utility methods and public methods for parsing configuration
  *
@@ -175,7 +178,7 @@ public abstract class AbstractConfig implements Serializable {
                             str = URL.encode(str);
                         }
                         if (parameter != null && parameter.append()) {
-                            String pre = parameters.get(Constants.DEFAULT_KEY + "." + key);
+                            String pre = parameters.get(DEFAULT_KEY + "." + key);
                             if (pre != null && pre.length() > 0) {
                                 str = pre + "," + str;
                             }
@@ -314,10 +317,10 @@ public abstract class AbstractConfig implements Serializable {
         if (StringUtils.isNotEmpty(value)) {
             String[] values = value.split("\\s*[,]+\\s*");
             for (String v : values) {
-                if (v.startsWith(Constants.REMOVE_VALUE_PREFIX)) {
+                if (v.startsWith(REMOVE_VALUE_PREFIX)) {
                     v = v.substring(1);
                 }
-                if (Constants.DEFAULT_KEY.equals(v)) {
+                if (DEFAULT_KEY.equals(v)) {
                     continue;
                 }
                 if (!ExtensionLoader.getExtensionLoader(type).hasExtension(v)) {
@@ -529,7 +532,7 @@ public abstract class AbstractConfig implements Serializable {
 
     @Parameter(excluded = true)
     public String getPrefix() {
-        return StringUtils.isNotEmpty(prefix) ? prefix : (Constants.DUBBO + "." + getTagName(this.getClass()));
+        return StringUtils.isNotEmpty(prefix) ? prefix : (CommonConstants.DUBBO + "." + getTagName(this.getClass()));
     }
 
     public void setPrefix(String prefix) {

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/AbstractInterfaceConfig.java

@@ -54,6 +54,16 @@ import java.util.Map;
 import java.util.Set;
 
 import static org.apache.dubbo.common.config.ConfigurationUtils.parseProperties;
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.FILE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PID_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.RELEASE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMESTAMP_KEY;
 import static org.apache.dubbo.common.extension.ExtensionLoader.getExtensionLoader;
 
 /**
@@ -298,16 +308,16 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
             for (RegistryConfig config : registries) {
                 String address = config.getAddress();
                 if (StringUtils.isEmpty(address)) {
-                    address = Constants.ANYHOST_VALUE;
+                    address = ANYHOST_VALUE;
                 }
                 if (!RegistryConfig.NO_AVAILABLE.equalsIgnoreCase(address)) {
                     Map<String, String> map = new HashMap<String, String>();
                     appendParameters(map, application);
                     appendParameters(map, config);
-                    map.put(Constants.PATH_KEY, RegistryService.class.getName());
+                    map.put(PATH_KEY, RegistryService.class.getName());
                     appendRuntimeParameters(map);
-                    if (!map.containsKey(Constants.PROTOCOL_KEY)) {
-                        map.put(Constants.PROTOCOL_KEY, Constants.DUBBO_PROTOCOL);
+                    if (!map.containsKey(PROTOCOL_KEY)) {
+                        map.put(PROTOCOL_KEY, Constants.DUBBO_PROTOCOL);
                     }
                     List<URL> urls = UrlUtils.parseURLs(address, map);
 
@@ -337,7 +347,7 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
     protected URL loadMonitor(URL registryURL) {
         checkMonitor();
         Map<String, String> map = new HashMap<String, String>();
-        map.put(Constants.INTERFACE_KEY, MonitorService.class.getName());
+        map.put(INTERFACE_KEY, MonitorService.class.getName());
         appendRuntimeParameters(map);
         //set ip
         String hostToRegistry = ConfigUtils.getSystemProperty(Constants.DUBBO_IP_TO_REGISTRY);
@@ -356,18 +366,18 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
             address = sysaddress;
         }
         if (ConfigUtils.isNotEmpty(address)) {
-            if (!map.containsKey(Constants.PROTOCOL_KEY)) {
+            if (!map.containsKey(PROTOCOL_KEY)) {
                 if (getExtensionLoader(MonitorFactory.class).hasExtension(Constants.LOGSTAT_PROTOCOL)) {
-                    map.put(Constants.PROTOCOL_KEY, Constants.LOGSTAT_PROTOCOL);
+                    map.put(PROTOCOL_KEY, Constants.LOGSTAT_PROTOCOL);
                 } else {
-                    map.put(Constants.PROTOCOL_KEY, Constants.DUBBO_PROTOCOL);
+                    map.put(PROTOCOL_KEY, Constants.DUBBO_PROTOCOL);
                 }
             }
             return UrlUtils.parseURL(address, map);
         } else if (Constants.REGISTRY_PROTOCOL.equals(monitor.getProtocol()) && registryURL != null) {
             return URLBuilder.from(registryURL)
                     .setProtocol(Constants.DUBBO_PROTOCOL)
-                    .addParameter(Constants.PROTOCOL_KEY, Constants.REGISTRY_PROTOCOL)
+                    .addParameter(PROTOCOL_KEY, Constants.REGISTRY_PROTOCOL)
                     .addParameterAndEncoded(Constants.REFER_KEY, StringUtils.toQueryString(map))
                     .build();
         }
@@ -376,10 +386,10 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
 
     static void appendRuntimeParameters(Map<String, String> map) {
         map.put(Constants.DUBBO_VERSION_KEY, Version.getProtocolVersion());
-        map.put(Constants.RELEASE_KEY, Version.getVersion());
-        map.put(Constants.TIMESTAMP_KEY, String.valueOf(System.currentTimeMillis()));
+        map.put(RELEASE_KEY, Version.getVersion());
+        map.put(TIMESTAMP_KEY, String.valueOf(System.currentTimeMillis()));
         if (ConfigUtils.getPid() > 0) {
-            map.put(Constants.PID_KEY, String.valueOf(ConfigUtils.getPid()));
+            map.put(PID_KEY, String.valueOf(ConfigUtils.getPid()));
         }
     }
 
@@ -519,7 +529,7 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
             configedRegistries.addAll(getSubProperties(Environment.getInstance().getAppExternalConfigurationMap(),
                     Constants.REGISTRIES_SUFFIX));
 
-            registryIds = String.join(Constants.COMMA_SEPARATOR, configedRegistries);
+            registryIds = String.join(COMMA_SEPARATOR, configedRegistries);
         }
 
         if (StringUtils.isEmpty(registryIds)) {
@@ -535,7 +545,7 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
                 );
             }
         } else {
-            String[] ids = Constants.COMMA_SPLIT_PATTERN.split(registryIds);
+            String[] ids = COMMA_SPLIT_PATTERN.split(registryIds);
             List<RegistryConfig> tmpRegistries = CollectionUtils.isNotEmpty(registries) ? registries : new ArrayList<>();
             Arrays.stream(ids).forEach(id -> {
                 if (tmpRegistries.stream().noneMatch(reg -> reg.getId().equals(id))) {
@@ -678,7 +688,7 @@ public abstract class AbstractInterfaceConfig extends AbstractMethodConfig {
     }
 
     public void setFilter(String filter) {
-        checkMultiExtension(Filter.class, Constants.FILE_KEY, filter);
+        checkMultiExtension(Filter.class, FILE_KEY, filter);
         this.filter = filter;
     }
 

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/AbstractReferenceConfig.java

@@ -22,6 +22,9 @@ import org.apache.dubbo.config.support.Parameter;
 import org.apache.dubbo.rpc.InvokerListener;
 import org.apache.dubbo.rpc.support.ProtocolUtils;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * AbstractConsumerConfig
  *
@@ -203,7 +206,7 @@ public abstract class AbstractReferenceConfig extends AbstractInterfaceConfig {
     }
 
     public void setVersion(String version) {
-        checkKey(Constants.VERSION_KEY, version);
+        checkKey(VERSION_KEY, version);
         this.version = version;
     }
 
@@ -212,7 +215,7 @@ public abstract class AbstractReferenceConfig extends AbstractInterfaceConfig {
     }
 
     public void setGroup(String group) {
-        checkKey(Constants.GROUP_KEY, group);
+        checkKey(GROUP_KEY, group);
         this.group = group;
     }
 }

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/AbstractServiceConfig.java

@@ -26,6 +26,9 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * AbstractServiceConfig
  *
@@ -116,7 +119,7 @@ public abstract class AbstractServiceConfig extends AbstractInterfaceConfig {
     }
 
     public void setVersion(String version) {
-        checkKey(Constants.VERSION_KEY, version);
+        checkKey(VERSION_KEY, version);
         this.version = version;
     }
 
@@ -125,7 +128,7 @@ public abstract class AbstractServiceConfig extends AbstractInterfaceConfig {
     }
 
     public void setGroup(String group) {
-        checkKey(Constants.GROUP_KEY, group);
+        checkKey(GROUP_KEY, group);
         this.group = group;
     }
 

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ApplicationConfig.java

@@ -27,6 +27,9 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DUMP_DIRECTORY;
+
 
 /**
  * The application info
@@ -130,7 +133,7 @@ public class ApplicationConfig extends AbstractConfig {
         setName(name);
     }
 
-    @Parameter(key = Constants.APPLICATION_KEY, required = true, useKeyAsProperty = false)
+    @Parameter(key = APPLICATION_KEY, required = true, useKeyAsProperty = false)
     public String getName() {
         return name;
     }
@@ -267,7 +270,7 @@ public class ApplicationConfig extends AbstractConfig {
         this.isDefault = isDefault;
     }
 
-    @Parameter(key = Constants.DUMP_DIRECTORY)
+    @Parameter(key = DUMP_DIRECTORY)
     public String getDumpDirectory() {
         return dumpDirectory;
     }
@@ -327,4 +330,4 @@ public class ApplicationConfig extends AbstractConfig {
         return !StringUtils.isEmpty(name);
     }
 
-}
+}

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ConfigCenterConfig.java

@@ -26,6 +26,10 @@ import org.apache.dubbo.config.support.Parameter;
 import java.util.Map;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
+
 /**
  * ConfigCenterConfig
  */
@@ -56,12 +60,12 @@ public class ConfigCenterConfig extends AbstractConfig {
     public URL toUrl() {
         Map<String, String> map = this.getMetaData();
         if (StringUtils.isEmpty(address)) {
-            address = Constants.ANYHOST_VALUE;
+            address = ANYHOST_VALUE;
         }
-        map.put(Constants.PATH_KEY, ConfigCenterConfig.class.getSimpleName());
+        map.put(PATH_KEY, ConfigCenterConfig.class.getSimpleName());
         // use 'zookeeper' as the default configcenter.
-        if (StringUtils.isEmpty(map.get(Constants.PROTOCOL_KEY))) {
-            map.put(Constants.PROTOCOL_KEY, Constants.ZOOKEEPER_PROTOCOL);
+        if (StringUtils.isEmpty(map.get(PROTOCOL_KEY))) {
+            map.put(PROTOCOL_KEY, Constants.ZOOKEEPER_PROTOCOL);
         }
         return UrlUtils.parseURL(address, map);
     }

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/MetadataReportConfig.java

@@ -16,13 +16,13 @@
  */
 package org.apache.dubbo.config;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.utils.StringUtils;
 import org.apache.dubbo.config.support.Parameter;
 
 import java.util.Map;
 
-import static org.apache.dubbo.common.Constants.PROPERTIES_CHAR_SEPERATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.DUBBO;
+import static org.apache.dubbo.common.constants.CommonConstants.PROPERTIES_CHAR_SEPERATOR;
 
 /**
  * MetadataReportConfig
@@ -158,7 +158,7 @@ public class MetadataReportConfig extends AbstractConfig {
     @Override
     @Parameter(excluded = true)
     public String getPrefix() {
-        return StringUtils.isNotEmpty(prefix) ? prefix : (Constants.DUBBO + "." + PREFIX_TAG);
+        return StringUtils.isNotEmpty(prefix) ? prefix : (DUBBO + "." + PREFIX_TAG);
     }
 
     @Override

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/MethodConfig.java

@@ -17,6 +17,7 @@
 package org.apache.dubbo.config;
 
 import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.utils.StringUtils;
 import org.apache.dubbo.config.annotation.Method;
 import org.apache.dubbo.config.support.Parameter;
@@ -318,7 +319,7 @@ public class MethodConfig extends AbstractMethodConfig {
     @Override
     @Parameter(excluded = true)
     public String getPrefix() {
-        return Constants.DUBBO + "." + service
+        return CommonConstants.DUBBO + "." + service
                 + (StringUtils.isEmpty(serviceId) ? "" : ("." + serviceId))
                 + "." + getName();
     }

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ProtocolConfig.java

@@ -33,6 +33,8 @@ import org.apache.dubbo.rpc.Protocol;
 
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.THREADPOOL_KEY;
+
 /**
  * ProtocolConfig
  *
@@ -269,7 +271,7 @@ public class ProtocolConfig extends AbstractConfig {
     }
 
     public void setThreadpool(String threadpool) {
-        checkExtension(ThreadPool.class, Constants.THREADPOOL_KEY, threadpool);
+        checkExtension(ThreadPool.class, THREADPOOL_KEY, threadpool);
         this.threadpool = threadpool;
     }
 

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ProviderConfig.java

@@ -29,6 +29,8 @@ import org.apache.dubbo.remoting.telnet.TelnetHandler;
 import java.util.ArrayList;
 import java.util.Arrays;
 
+import static org.apache.dubbo.common.constants.CommonConstants.THREADPOOL_KEY;
+
 /**
  * The service provider default configuration
  *
@@ -217,7 +219,7 @@ public class ProviderConfig extends AbstractServiceConfig {
     }
 
     public void setThreadpool(String threadpool) {
-        checkExtension(ThreadPool.class, Constants.THREADPOOL_KEY, threadpool);
+        checkExtension(ThreadPool.class, THREADPOOL_KEY, threadpool);
         this.threadpool = threadpool;
     }
 

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ReferenceConfig.java

@@ -56,6 +56,16 @@ import java.util.List;
 import java.util.Map;
 import java.util.Properties;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANY_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.DUBBO;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.METHODS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.REVISION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.SEMICOLON_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
 import static org.apache.dubbo.common.utils.NetUtils.isInvalidLocalHost;
 
 /**
@@ -261,24 +271,24 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
         checkMock(interfaceClass);
         Map<String, String> map = new HashMap<String, String>();
 
-        map.put(Constants.SIDE_KEY, Constants.CONSUMER_SIDE);
+        map.put(SIDE_KEY, CONSUMER_SIDE);
 
         appendRuntimeParameters(map);
         if (!isGeneric()) {
             String revision = Version.getVersion(interfaceClass, version);
             if (revision != null && revision.length() > 0) {
-                map.put(Constants.REVISION_KEY, revision);
+                map.put(REVISION_KEY, revision);
             }
 
             String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames();
             if (methods.length == 0) {
                 logger.warn("No method found in service interface " + interfaceClass.getName());
-                map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
+                map.put(METHODS_KEY, ANY_VALUE);
             } else {
-                map.put(Constants.METHODS_KEY, StringUtils.join(new HashSet<String>(Arrays.asList(methods)), Constants.COMMA_SEPARATOR));
+                map.put(METHODS_KEY, StringUtils.join(new HashSet<String>(Arrays.asList(methods)), COMMA_SEPARATOR));
             }
         }
-        map.put(Constants.INTERFACE_KEY, interfaceName);
+        map.put(INTERFACE_KEY, interfaceName);
         appendParameters(map, metrics);
         appendParameters(map, application);
         appendParameters(map, module);
@@ -333,14 +343,14 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
     @SuppressWarnings({"unchecked", "rawtypes", "deprecation"})
     private T createProxy(Map<String, String> map) {
         if (shouldJvmRefer(map)) {
-            URL url = new URL(Constants.LOCAL_PROTOCOL, Constants.LOCALHOST_VALUE, 0, interfaceClass.getName()).addParameters(map);
+            URL url = new URL(Constants.LOCAL_PROTOCOL, LOCALHOST_VALUE, 0, interfaceClass.getName()).addParameters(map);
             invoker = REF_PROTOCOL.refer(interfaceClass, url);
             if (logger.isInfoEnabled()) {
                 logger.info("Using injvm service " + interfaceClass.getName());
             }
         } else {
             if (url != null && url.length() > 0) { // user specified URL, could be peer-to-peer address, or register center's address.
-                String[] us = Constants.SEMICOLON_SPLIT_PATTERN.split(url);
+                String[] us = SEMICOLON_SPLIT_PATTERN.split(url);
                 if (us != null && us.length > 0) {
                     for (String u : us) {
                         URL url = URL.valueOf(u);
@@ -410,7 +420,7 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
          */
         MetadataReportService metadataReportService = null;
         if ((metadataReportService = getMetadataReportService()) != null) {
-            URL consumerURL = new URL(Constants.CONSUMER_PROTOCOL, map.remove(Constants.REGISTER_IP_KEY), 0, map.get(Constants.INTERFACE_KEY), map);
+            URL consumerURL = new URL(Constants.CONSUMER_PROTOCOL, map.remove(Constants.REGISTER_IP_KEY), 0, map.get(INTERFACE_KEY), map);
             metadataReportService.publishConsumer(consumerURL);
         }
         // create service proxy
@@ -609,7 +619,7 @@ public class ReferenceConfig<T> extends AbstractReferenceConfig {
     @Override
     @Parameter(excluded = true)
     public String getPrefix() {
-        return Constants.DUBBO + ".reference." + interfaceName;
+        return DUBBO + ".reference." + interfaceName;
     }
 
     private void resolveFile() {

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/RegistryConfig.java

@@ -23,6 +23,9 @@ import org.apache.dubbo.config.support.Parameter;
 
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.FILE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
+
 /**
  * RegistryConfig
  *
@@ -158,7 +161,7 @@ public class RegistryConfig extends AbstractConfig {
     }
 
     public void setProtocol(String protocol) {
-        checkName(Constants.PROTOCOL_KEY, protocol);
+        checkName(PROTOCOL_KEY, protocol);
         this.protocol = protocol;
         this.updateIdIfAbsent(protocol);
     }
@@ -240,7 +243,7 @@ public class RegistryConfig extends AbstractConfig {
     }
 
     public void setFile(String file) {
-        checkPathLength(Constants.FILE_KEY, file);
+        checkPathLength(FILE_KEY, file);
         this.file = file;
     }
 

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ServiceConfig.java

@@ -62,7 +62,16 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
 
-import static org.apache.dubbo.common.Constants.LOCALHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.ANY_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+import static org.apache.dubbo.common.constants.CommonConstants.DUBBO;
+import static org.apache.dubbo.common.constants.CommonConstants.LOCALHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.METHODS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.REVISION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
 import static org.apache.dubbo.common.utils.NetUtils.getAvailablePort;
 import static org.apache.dubbo.common.utils.NetUtils.getLocalHost;
 import static org.apache.dubbo.common.utils.NetUtils.isInvalidLocalHost;
@@ -436,11 +445,11 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
     private void doExportUrlsFor1Protocol(ProtocolConfig protocolConfig, List<URL> registryURLs) {
         String name = protocolConfig.getName();
         if (StringUtils.isEmpty(name)) {
-            name = Constants.DUBBO;
+            name = DUBBO;
         }
 
         Map<String, String> map = new HashMap<String, String>();
-        map.put(Constants.SIDE_KEY, Constants.PROVIDER_SIDE);
+        map.put(SIDE_KEY, PROVIDER_SIDE);
 
         appendRuntimeParameters(map);
         appendParameters(map, metrics);
@@ -509,19 +518,19 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
 
         if (ProtocolUtils.isGeneric(generic)) {
             map.put(Constants.GENERIC_KEY, generic);
-            map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
+            map.put(METHODS_KEY, ANY_VALUE);
         } else {
             String revision = Version.getVersion(interfaceClass, version);
             if (revision != null && revision.length() > 0) {
-                map.put(Constants.REVISION_KEY, revision);
+                map.put(REVISION_KEY, revision);
             }
 
             String[] methods = Wrapper.getWrapper(interfaceClass).getMethodNames();
             if (methods.length == 0) {
                 logger.warn("No method found in service interface " + interfaceClass.getName());
-                map.put(Constants.METHODS_KEY, Constants.ANY_VALUE);
+                map.put(METHODS_KEY, ANY_VALUE);
             } else {
-                map.put(Constants.METHODS_KEY, StringUtils.join(new HashSet<String>(Arrays.asList(methods)), ","));
+                map.put(METHODS_KEY, StringUtils.join(new HashSet<String>(Arrays.asList(methods)), ","));
             }
         }
         if (!ConfigUtils.isEmpty(token)) {
@@ -696,7 +705,7 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
             hostToRegistry = hostToBind;
         }
 
-        map.put(Constants.ANYHOST_KEY, String.valueOf(anyhost));
+        map.put(ANYHOST_KEY, String.valueOf(anyhost));
 
         return hostToRegistry;
     }
@@ -863,7 +872,7 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
                 );
             }
         } else {
-            String[] arr = Constants.COMMA_SPLIT_PATTERN.split(protocolIds);
+            String[] arr = COMMA_SPLIT_PATTERN.split(protocolIds);
             List<ProtocolConfig> tmpProtocols = CollectionUtils.isNotEmpty(protocols) ? protocols : new ArrayList<>();
             Arrays.stream(arr).forEach(id -> {
                 if (tmpProtocols.stream().noneMatch(prot -> prot.getId().equals(id))) {
@@ -943,7 +952,7 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
     }
 
     public void setPath(String path) {
-        checkPathName(Constants.PATH_KEY, path);
+        checkPathName(PATH_KEY, path);
         this.path = path;
     }
 
@@ -1024,6 +1033,6 @@ public class ServiceConfig<T> extends AbstractServiceConfig {
     @Override
     @Parameter(excluded = true)
     public String getPrefix() {
-        return Constants.DUBBO + ".service." + interfaceName;
+        return DUBBO + ".service." + interfaceName;
     }
 }

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/context/ConfigManager.java

@@ -35,7 +35,7 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 
-import static org.apache.dubbo.common.Constants.DEFAULT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_KEY;
 
 /**
  * TODO

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/config/AbstractInterfaceConfigTest.java

@@ -18,6 +18,7 @@ package org.apache.dubbo.config;
 
 import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.utils.ConfigUtils;
 import org.apache.dubbo.config.api.Greeting;
 import org.apache.dubbo.config.context.ConfigManager;
@@ -51,13 +52,13 @@ public class AbstractInterfaceConfigTest {
 
     @BeforeAll
     public static void setUp(@TempDir Path folder) {
-        dubboProperties = folder.resolve(Constants.DUBBO_PROPERTIES_KEY).toFile();
-        System.setProperty(Constants.DUBBO_PROPERTIES_KEY, dubboProperties.getAbsolutePath());
+        dubboProperties = folder.resolve(CommonConstants.DUBBO_PROPERTIES_KEY).toFile();
+        System.setProperty(CommonConstants.DUBBO_PROPERTIES_KEY, dubboProperties.getAbsolutePath());
     }
 
     @AfterAll
     public static void tearDown() {
-        System.clearProperty(Constants.DUBBO_PROPERTIES_KEY);
+        System.clearProperty(CommonConstants.DUBBO_PROPERTIES_KEY);
     }
 
     @AfterEach

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/config/ApplicationConfigTest.java

@@ -26,13 +26,15 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.DUMP_DIRECTORY;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.hasEntry;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.sameInstance;
 import static org.hamcrest.collection.IsCollectionWithSize.hasSize;
-import static org.hamcrest.MatcherAssert.assertThat;
 
 public class ApplicationConfigTest {
     @Test
@@ -44,7 +46,7 @@ public class ApplicationConfigTest {
         assertThat(application.getName(), equalTo("app2"));
         Map<String, String> parameters = new HashMap<String, String>();
         ApplicationConfig.appendParameters(parameters, application);
-        assertThat(parameters, hasEntry(Constants.APPLICATION_KEY, "app2"));
+        assertThat(parameters, hasEntry(APPLICATION_KEY, "app2"));
     }
 
     @Test
@@ -138,7 +140,7 @@ public class ApplicationConfigTest {
         assertThat(application.getDumpDirectory(), equalTo("/dump"));
         Map<String, String> parameters = new HashMap<String, String>();
         ApplicationConfig.appendParameters(parameters, application);
-        assertThat(parameters, hasEntry(Constants.DUMP_DIRECTORY, "/dump"));
+        assertThat(parameters, hasEntry(DUMP_DIRECTORY, "/dump"));
     }
 
     @Test

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/config/ServiceConfigTest.java

@@ -46,6 +46,12 @@ import java.util.concurrent.TimeUnit;
 import static org.apache.dubbo.common.Constants.GENERIC_SERIALIZATION_BEAN;
 import static org.apache.dubbo.common.Constants.GENERIC_SERIALIZATION_DEFAULT;
 import static org.apache.dubbo.common.Constants.GENERIC_SERIALIZATION_NATIVE_JAVA;
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.METHODS_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.CoreMatchers.is;
@@ -131,17 +137,17 @@ public class ServiceConfigTest {
         URL url = service.toUrl();
         assertThat(url.getProtocol(), equalTo("mockprotocol2"));
         assertThat(url.getPath(), equalTo(DemoService.class.getName()));
-        assertThat(url.getParameters(), hasEntry(Constants.ANYHOST_KEY, "true"));
-        assertThat(url.getParameters(), hasEntry(Constants.APPLICATION_KEY, "app"));
+        assertThat(url.getParameters(), hasEntry(ANYHOST_KEY, "true"));
+        assertThat(url.getParameters(), hasEntry(APPLICATION_KEY, "app"));
         assertThat(url.getParameters(), hasKey(RemotingConstants.BIND_IP_KEY));
         assertThat(url.getParameters(), hasKey(RemotingConstants.BIND_PORT_KEY));
         assertThat(url.getParameters(), hasEntry(Constants.EXPORT_KEY, "true"));
         assertThat(url.getParameters(), hasEntry("echo.0.callback", "false"));
         assertThat(url.getParameters(), hasEntry(Constants.GENERIC_KEY, "false"));
-        assertThat(url.getParameters(), hasEntry(Constants.INTERFACE_KEY, DemoService.class.getName()));
-        assertThat(url.getParameters(), hasKey(Constants.METHODS_KEY));
-        assertThat(url.getParameters().get(Constants.METHODS_KEY), containsString("echo"));
-        assertThat(url.getParameters(), hasEntry(Constants.SIDE_KEY, Constants.PROVIDER));
+        assertThat(url.getParameters(), hasEntry(INTERFACE_KEY, DemoService.class.getName()));
+        assertThat(url.getParameters(), hasKey(METHODS_KEY));
+        assertThat(url.getParameters().get(METHODS_KEY), containsString("echo"));
+        assertThat(url.getParameters(), hasEntry(SIDE_KEY, PROVIDER));
         Mockito.verify(protocolDelegate).export(Mockito.any(Invoker.class));
     }
 

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/config/mock/MockRegistry.java

@@ -24,6 +24,8 @@ import org.apache.dubbo.registry.Registry;
 import java.util.ArrayList;
 import java.util.List;
 
+import static org.apache.dubbo.common.constants.CommonConstants.METHODS_KEY;
+
 /**
  * TODO Comment of MockRegistry
  */
@@ -84,7 +86,7 @@ public class MockRegistry implements Registry {
 
         urls.add(url.setProtocol("mockprotocol")
                 .removeParameter(Constants.CATEGORY_KEY)
-                .addParameter(Constants.METHODS_KEY, "sayHello"));
+                .addParameter(METHODS_KEY, "sayHello"));
 
         listener.notify(urls);
     }

dubbo-config/dubbo-config-spring/src/main/java/org/apache/dubbo/config/spring/ReferenceBean.java

@@ -16,18 +16,17 @@
  */
 package org.apache.dubbo.config.spring;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.utils.CollectionUtils;
 import org.apache.dubbo.common.utils.StringUtils;
 import org.apache.dubbo.config.ApplicationConfig;
 import org.apache.dubbo.config.ConfigCenterConfig;
 import org.apache.dubbo.config.ConsumerConfig;
 import org.apache.dubbo.config.MetadataReportConfig;
+import org.apache.dubbo.config.MetricsConfig;
 import org.apache.dubbo.config.ModuleConfig;
 import org.apache.dubbo.config.MonitorConfig;
 import org.apache.dubbo.config.ReferenceConfig;
 import org.apache.dubbo.config.RegistryConfig;
-import org.apache.dubbo.config.MetricsConfig;
 import org.apache.dubbo.config.annotation.Reference;
 import org.apache.dubbo.config.spring.extension.SpringExtensionFactory;
 import org.apache.dubbo.config.support.Parameter;
@@ -44,6 +43,8 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+
 /**
  * ReferenceFactoryBean
  */
@@ -158,7 +159,7 @@ public class ReferenceBean<T> extends ReferenceConfig<T> implements FactoryBean,
             if (registryConfigMap != null && registryConfigMap.size() > 0) {
                 List<RegistryConfig> registryConfigs = new ArrayList<>();
                 if (StringUtils.isNotEmpty(registryIds)) {
-                    Arrays.stream(Constants.COMMA_SPLIT_PATTERN.split(registryIds)).forEach(id -> {
+                    Arrays.stream(COMMA_SPLIT_PATTERN.split(registryIds)).forEach(id -> {
                         if (registryConfigMap.containsKey(id)) {
                             registryConfigs.add(registryConfigMap.get(id));
                         }

dubbo-config/dubbo-config-spring/src/main/java/org/apache/dubbo/config/spring/ServiceBean.java

@@ -16,19 +16,18 @@
  */
 package org.apache.dubbo.config.spring;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.utils.CollectionUtils;
 import org.apache.dubbo.common.utils.StringUtils;
-import org.apache.dubbo.config.ProtocolConfig;
-import org.apache.dubbo.config.ProviderConfig;
-import org.apache.dubbo.config.ServiceConfig;
-import org.apache.dubbo.config.MetricsConfig;
-import org.apache.dubbo.config.RegistryConfig;
+import org.apache.dubbo.config.ApplicationConfig;
 import org.apache.dubbo.config.ConfigCenterConfig;
 import org.apache.dubbo.config.MetadataReportConfig;
-import org.apache.dubbo.config.MonitorConfig;
+import org.apache.dubbo.config.MetricsConfig;
 import org.apache.dubbo.config.ModuleConfig;
-import org.apache.dubbo.config.ApplicationConfig;
+import org.apache.dubbo.config.MonitorConfig;
+import org.apache.dubbo.config.ProtocolConfig;
+import org.apache.dubbo.config.ProviderConfig;
+import org.apache.dubbo.config.RegistryConfig;
+import org.apache.dubbo.config.ServiceConfig;
 import org.apache.dubbo.config.annotation.Service;
 import org.apache.dubbo.config.spring.context.event.ServiceBeanExportedEvent;
 import org.apache.dubbo.config.spring.extension.SpringExtensionFactory;
@@ -50,6 +49,7 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
 import static org.apache.dubbo.config.spring.util.BeanFactoryUtils.addApplicationListener;
 
 /**
@@ -200,7 +200,7 @@ public class ServiceBean<T> extends ServiceConfig<T> implements InitializingBean
             if (CollectionUtils.isNotEmptyMap(registryConfigMap)) {
                 List<RegistryConfig> registryConfigs = new ArrayList<>();
                 if (StringUtils.isNotEmpty(registryIds)) {
-                    Arrays.stream(Constants.COMMA_SPLIT_PATTERN.split(registryIds)).forEach(id -> {
+                    Arrays.stream(COMMA_SPLIT_PATTERN.split(registryIds)).forEach(id -> {
                         if (registryConfigMap.containsKey(id)) {
                             registryConfigs.add(registryConfigMap.get(id));
                         }
@@ -285,7 +285,7 @@ public class ServiceBean<T> extends ServiceConfig<T> implements InitializingBean
             if (protocolConfigMap != null && protocolConfigMap.size() > 0) {
                 List<ProtocolConfig> protocolConfigs = new ArrayList<ProtocolConfig>();
                 if (StringUtils.isNotEmpty(getProtocolIds())) {
-                    Arrays.stream(Constants.COMMA_SPLIT_PATTERN.split(getProtocolIds()))
+                    Arrays.stream(COMMA_SPLIT_PATTERN.split(getProtocolIds()))
                             .forEach(id -> {
                                 if (protocolConfigMap.containsKey(id)) {
                                     protocolConfigs.add(protocolConfigMap.get(id));

dubbo-config/dubbo-config-spring/src/main/java/org/apache/dubbo/config/spring/beans/factory/annotation/AnnotationBeanNameBuilder.java

@@ -16,7 +16,7 @@
  */
 package org.apache.dubbo.config.spring.beans.factory.annotation;
 
-import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.config.annotation.Reference;
 import org.apache.dubbo.config.annotation.Service;
 import org.apache.dubbo.registry.Registry;
@@ -24,8 +24,8 @@ import org.apache.dubbo.registry.Registry;
 import org.springframework.core.env.Environment;
 
 import static org.apache.dubbo.common.Constants.CONSUMERS_CATEGORY;
-import static org.apache.dubbo.common.Constants.DEFAULT_PROTOCOL;
 import static org.apache.dubbo.common.Constants.PROVIDERS_CATEGORY;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_PROTOCOL;
 import static org.apache.dubbo.config.spring.util.AnnotationUtils.resolveInterfaceName;
 import static org.springframework.util.StringUtils.arrayToCommaDelimitedString;
 import static org.springframework.util.StringUtils.hasText;
@@ -114,8 +114,8 @@ class AnnotationBeanNameBuilder {
      *
      * @param protocols one or more protocols
      * @return if <code>protocols</code> == <code>null</code>, it will return
-     * {@link Constants#DEFAULT_PROTOCOL "dubbo"} as the default protocol
-     * @see Constants#DEFAULT_PROTOCOL
+     * {@link CommonConstants#DEFAULT_PROTOCOL "dubbo"} as the default protocol
+     * @see CommonConstants#DEFAULT_PROTOCOL
      */
     private static String resolveProtocol(String... protocols) {
         String protocol = arrayToCommaDelimitedString(protocols);

dubbo-config/dubbo-config-spring/src/main/java/org/apache/dubbo/config/spring/schema/DubboBeanDefinitionParser.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.config.spring.schema;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
 import org.apache.dubbo.common.utils.ReflectUtils;
@@ -52,6 +51,8 @@ import java.util.HashSet;
 import java.util.Set;
 import java.util.regex.Pattern;
 
+import static org.apache.dubbo.common.constants.CommonConstants.HIDE_KEY_PREFIX;
+
 /**
  * AbstractBeanDefinitionParser
  *
@@ -316,7 +317,7 @@ public class DubboBeanDefinitionParser implements BeanDefinitionParser {
                         String value = ((Element) node).getAttribute("value");
                         boolean hide = "true".equals(((Element) node).getAttribute("hide"));
                         if (hide) {
-                            key = Constants.HIDE_KEY_PREFIX + key;
+                            key = HIDE_KEY_PREFIX + key;
                         }
                         parameters.put(key, new TypedStringValue(value, String.class));
                     }

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/SimpleRegistryExporter.java

@@ -17,7 +17,6 @@
 package org.apache.dubbo.config.spring;
 
 import org.apache.dubbo.common.Constants;
-import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.URLBuilder;
 import org.apache.dubbo.common.extension.ExtensionLoader;
 import org.apache.dubbo.common.utils.NetUtils;
@@ -29,6 +28,8 @@ import org.apache.dubbo.rpc.ProxyFactory;
 import java.io.IOException;
 import java.net.ServerSocket;
 
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+
 /**
  * SimpleRegistryExporter
  */
@@ -55,7 +56,7 @@ public class SimpleRegistryExporter {
         return protocol.export(proxyFactory.getInvoker(registryService, RegistryService.class,
                 new URLBuilder(Constants.DUBBO_PROTOCOL, NetUtils.getLocalHost(), port, RegistryService.class.getName())
                         .setPath(RegistryService.class.getName())
-                        .addParameter(Constants.INTERFACE_KEY, RegistryService.class.getName())
+                        .addParameter(INTERFACE_KEY, RegistryService.class.getName())
                         .addParameter(Constants.CLUSTER_STICKY_KEY, "true")
                         .addParameter(Constants.CALLBACK_INSTANCES_LIMIT_KEY, "1000")
                         .addParameter("ondisconnect", "disconnect")

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/beans/factory/annotation/ReferenceBeanBuilderTest.java

@@ -38,7 +38,6 @@ import static org.springframework.util.ReflectionUtils.findField;
 /**
  * {@link ReferenceBeanBuilder} Test
  *
- * @author <a href="mailto:mercyblitz@gmail.com">Mercy</a>
  * @see ReferenceBeanBuilder
  * @see Reference
  * @since 2.6.4

dubbo-configcenter/dubbo-configcenter-apollo/src/main/java/org/apache/dubbo/configcenter/support/apollo/ApolloDynamicConfiguration.java

@@ -41,6 +41,9 @@ import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.CopyOnWriteArraySet;
 import java.util.stream.Collectors;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANYHOST_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+
 /**
  * Apollo implementation, https://github.com/ctripcorp/apollo
  */
@@ -64,7 +67,7 @@ public class ApolloDynamicConfiguration implements DynamicConfiguration {
         if (configEnv != null) {
             System.setProperty(APOLLO_ENV_KEY, configEnv);
         }
-        if (StringUtils.isEmpty(System.getProperty(APOLLO_ENV_KEY)) && !Constants.ANYHOST_VALUE.equals(configAddr)) {
+        if (StringUtils.isEmpty(System.getProperty(APOLLO_ENV_KEY)) && !ANYHOST_VALUE.equals(configAddr)) {
             System.setProperty(APOLLO_ADDR_KEY, configAddr);
         }
         if (configCluster != null) {
@@ -89,7 +92,7 @@ public class ApolloDynamicConfiguration implements DynamicConfiguration {
     private String getAddressWithProtocolPrefix (URL url) {
         String address = url.getBackupAddress();
         if (StringUtils.isNotEmpty(address)) {
-            address = Arrays.stream(Constants.COMMA_SPLIT_PATTERN.split(address))
+            address = Arrays.stream(COMMA_SPLIT_PATTERN.split(address))
                     .map(addr ->  {
                         if (addr.startsWith(APOLLO_PROTOCOL_PREFIX)) {
                             return addr;

dubbo-configcenter/dubbo-configcenter-consul/src/main/java/org/apache/dubbo/configcenter/consul/ConsulDynamicConfiguration.java

@@ -40,7 +40,7 @@ import java.util.concurrent.ExecutorService;
 
 import static java.util.concurrent.Executors.newCachedThreadPool;
 import static org.apache.dubbo.common.Constants.CONFIG_NAMESPACE_KEY;
-import static org.apache.dubbo.common.Constants.PATH_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
 import static org.apache.dubbo.configcenter.ConfigChangeType.ADDED;
 
 /**

dubbo-configcenter/dubbo-configcenter-etcd/src/main/java/org/apache/dubbo/configcenter/support/etcd/EtcdDynamicConfiguration.java

@@ -40,7 +40,7 @@ import java.util.concurrent.ConcurrentMap;
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.apache.dubbo.common.Constants.CONFIG_NAMESPACE_KEY;
-import static org.apache.dubbo.common.Constants.PATH_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
 
 /**
  * The etcd implementation of {@link DynamicConfiguration}

dubbo-configcenter/dubbo-configcenter-nacos/src/main/java/org/apache/dubbo/configcenter/support/nacos/NacosDynamicConfiguration.java

@@ -17,10 +17,6 @@
 
 package org.apache.dubbo.configcenter.support.nacos;
 
-import com.alibaba.nacos.api.NacosFactory;
-import com.alibaba.nacos.api.config.ConfigService;
-import com.alibaba.nacos.api.config.listener.AbstractSharedListener;
-import com.alibaba.nacos.api.exception.NacosException;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -30,24 +26,30 @@ import org.apache.dubbo.configcenter.ConfigChangeType;
 import org.apache.dubbo.configcenter.ConfigurationListener;
 import org.apache.dubbo.configcenter.DynamicConfiguration;
 
+import com.alibaba.nacos.api.NacosFactory;
+import com.alibaba.nacos.api.config.ConfigService;
+import com.alibaba.nacos.api.config.listener.AbstractSharedListener;
+import com.alibaba.nacos.api.exception.NacosException;
+
 import java.util.Map;
 import java.util.Properties;
 import java.util.Set;
-import java.util.concurrent.Executor;
-import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.CopyOnWriteArraySet;
+import java.util.concurrent.Executor;
+
 import static com.alibaba.nacos.api.PropertyKeyConst.ACCESS_KEY;
 import static com.alibaba.nacos.api.PropertyKeyConst.CLUSTER_NAME;
 import static com.alibaba.nacos.api.PropertyKeyConst.ENDPOINT;
+import static com.alibaba.nacos.api.PropertyKeyConst.NAMESPACE;
 import static com.alibaba.nacos.api.PropertyKeyConst.SECRET_KEY;
 import static com.alibaba.nacos.api.PropertyKeyConst.SERVER_ADDR;
-import static com.alibaba.nacos.api.PropertyKeyConst.NAMESPACE;
 import static com.alibaba.nacos.client.naming.utils.UtilAndComs.NACOS_NAMING_LOG_NAME;
 import static org.apache.dubbo.common.constants.RemotingConstants.BACKUP_KEY;
 import static org.apache.dubbo.common.Constants.CONFIG_NAMESPACE_KEY;
-import static org.apache.dubbo.common.Constants.GROUP_CHAR_SEPERATOR;
-import static org.apache.dubbo.common.Constants.PROPERTIES_CHAR_SEPERATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_CHAR_SEPERATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.PROPERTIES_CHAR_SEPERATOR;
 
 /**
  * The nacos implementation of {@link DynamicConfiguration}

dubbo-configcenter/dubbo-configcenter-nacos/src/main/java/org/apache/dubbo/configcenter/support/nacos/NacosDynamicConfigurationFactory.java

@@ -17,12 +17,13 @@
 
 package org.apache.dubbo.configcenter.support.nacos;
 
-import com.alibaba.nacos.api.PropertyKeyConst;
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.configcenter.AbstractDynamicConfigurationFactory;
 import org.apache.dubbo.configcenter.DynamicConfiguration;
 
+import com.alibaba.nacos.api.PropertyKeyConst;
+
 /**
  * The nacos implementation of {@link AbstractDynamicConfigurationFactory}
  */
@@ -31,7 +32,7 @@ public class NacosDynamicConfigurationFactory extends AbstractDynamicConfigurati
     @Override
     protected DynamicConfiguration createDynamicConfiguration(URL url) {
         URL nacosURL = url;
-        if (Constants.DUBBO.equals(url.getParameter(PropertyKeyConst.NAMESPACE))) {
+        if (CommonConstants.DUBBO.equals(url.getParameter(PropertyKeyConst.NAMESPACE))) {
             // Nacos use empty string as default name space, replace default namespace "dubbo" to ""
             nacosURL = url.removeParameter(PropertyKeyConst.NAMESPACE);
         }

dubbo-container/dubbo-container-api/src/main/java/org/apache/dubbo/container/Main.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.container;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.extension.ExtensionLoader;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -31,6 +30,8 @@ import java.util.List;
 import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.ReentrantLock;
 
+import static org.apache.dubbo.common.constants.CommonConstants.COMMA_SPLIT_PATTERN;
+
 /**
  * Main. (API, Static, ThreadSafe)
  *
@@ -54,7 +55,7 @@ public class Main {
         try {
             if (ArrayUtils.isEmpty(args)) {
                 String config = ConfigUtils.getProperty(CONTAINER_KEY, loader.getDefaultExtensionName());
-                args = Constants.COMMA_SPLIT_PATTERN.split(config);
+                args = COMMA_SPLIT_PATTERN.split(config);
             }
 
             final List<Container> containers = new ArrayList<Container>();

dubbo-filter/dubbo-filter-cache/src/main/java/org/apache/dubbo/cache/filter/CacheFilter.java

@@ -19,6 +19,7 @@ package org.apache.dubbo.cache.filter;
 import org.apache.dubbo.cache.Cache;
 import org.apache.dubbo.cache.CacheFactory;
 import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.extension.Activate;
 import org.apache.dubbo.common.utils.ConfigUtils;
 import org.apache.dubbo.common.utils.StringUtils;
@@ -45,10 +46,10 @@ import java.io.Serializable;
  *        3)<dubbo:provider cache="expiring" />
  *        4)<dubbo:consumer cache="jcache" />
  *
- *If cache type is defined in method level then method level type will get precedence. According to above provided
- *example, if service has two method, method1 and method2, method2 will have cache type as <b>threadlocal</b> where others will
- *be backed by <b>lru</b>
- *</pre>
+ * If cache type is defined in method level then method level type will get precedence. According to above provided
+ * example, if service has two method, method1 and method2, method2 will have cache type as <b>threadlocal</b> where others will
+ * be backed by <b>lru</b>
+ * </pre>
  *
  * @see org.apache.dubbo.rpc.Filter
  * @see org.apache.dubbo.cache.support.lru.LruCacheFactory
@@ -59,9 +60,8 @@ import java.io.Serializable;
  * @see org.apache.dubbo.cache.support.threadlocal.ThreadLocalCache
  * @see org.apache.dubbo.cache.support.expiring.ExpiringCacheFactory
  * @see org.apache.dubbo.cache.support.expiring.ExpiringCache
- *
  */
-@Activate(group = {Constants.CONSUMER, Constants.PROVIDER}, value = Constants.CACHE_KEY)
+@Activate(group = {CommonConstants.CONSUMER, CommonConstants.PROVIDER}, value = Constants.CACHE_KEY)
 public class CacheFilter implements Filter {
 
     private CacheFactory cacheFactory;
@@ -81,6 +81,7 @@ public class CacheFilter implements Filter {
      * If cache is configured, dubbo will invoke method on each method call. If cache value is returned by cache store
      * then it will return otherwise call the remote method and return value. If remote method's return valeu has error
      * then it will not cache the value.
+     *
      * @param invoker    service
      * @param invocation invocation.
      * @return Cache returned value if found by the underlying cache store. If cache miss it will call target method.
@@ -95,7 +96,7 @@ public class CacheFilter implements Filter {
                 Object value = cache.get(key);
                 if (value != null) {
                     if (value instanceof ValueWrapper) {
-                        return new RpcResult(((ValueWrapper)value).get());
+                        return new RpcResult(((ValueWrapper) value).get());
                     } else {
                         return new RpcResult(value);
                     }
@@ -113,13 +114,13 @@ public class CacheFilter implements Filter {
     /**
      * Cache value wrapper.
      */
-    static class ValueWrapper implements Serializable{
+    static class ValueWrapper implements Serializable {
 
         private static final long serialVersionUID = -1777337318019193256L;
 
         private final Object value;
 
-        public ValueWrapper(Object value){
+        public ValueWrapper(Object value) {
             this.value = value;
         }
 

dubbo-filter/dubbo-filter-cache/src/main/java/org/apache/dubbo/cache/support/AbstractCacheFactory.java

@@ -18,13 +18,14 @@ package org.apache.dubbo.cache.support;
 
 import org.apache.dubbo.cache.Cache;
 import org.apache.dubbo.cache.CacheFactory;
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.rpc.Invocation;
 
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 
+import static org.apache.dubbo.common.constants.CommonConstants.METHOD_KEY;
+
 /**
  * AbstractCacheFactory is a default implementation of {@link CacheFactory}. It abstract out the key formation from URL along with
  * invocation method. It initially check if the value for key already present in own local in-memory store then it won't check underlying storage cache {@link Cache}.
@@ -51,7 +52,7 @@ public abstract class AbstractCacheFactory implements CacheFactory {
      */
     @Override
     public Cache getCache(URL url, Invocation invocation) {
-        url = url.addParameter(Constants.METHOD_KEY, invocation.getMethodName());
+        url = url.addParameter(METHOD_KEY, invocation.getMethodName());
         String key = url.toFullString();
         Cache cache = caches.get(key);
         if (cache == null) {

dubbo-filter/dubbo-filter-cache/src/main/java/org/apache/dubbo/cache/support/jcache/JCache.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.cache.support.jcache;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.StringUtils;
 
@@ -30,6 +29,8 @@ import javax.cache.expiry.Duration;
 import javax.cache.spi.CachingProvider;
 import java.util.concurrent.TimeUnit;
 
+import static org.apache.dubbo.common.constants.CommonConstants.METHOD_KEY;
+
 /**
  * This class store the cache value per thread. If a service,method,consumer or provided is configured with key <b>cache</b>
  * with value <b>jcache</b>, dubbo initialize the instance of this class using {@link JCacheFactory} to store method's returns value
@@ -45,7 +46,7 @@ public class JCache implements org.apache.dubbo.cache.Cache {
     private final Cache<Object, Object> store;
 
     public JCache(URL url) {
-        String method = url.getParameter(Constants.METHOD_KEY, "");
+        String method = url.getParameter(METHOD_KEY, "");
         String key = url.getAddress() + "." + url.getServiceKey() + "." + method;
         // jcache parameter is the full-qualified class name of SPI implementation
         String type = url.getParameter("jcache");

dubbo-filter/dubbo-filter-validation/src/main/java/org/apache/dubbo/validation/filter/ValidationFilter.java

@@ -17,6 +17,7 @@
 package org.apache.dubbo.validation.filter;
 
 import org.apache.dubbo.common.Constants;
+import org.apache.dubbo.common.constants.CommonConstants;
 import org.apache.dubbo.common.extension.Activate;
 import org.apache.dubbo.common.utils.ConfigUtils;
 import org.apache.dubbo.rpc.Filter;
@@ -55,7 +56,7 @@ import org.apache.dubbo.validation.Validator;
  * @see Filter
  * @see org.apache.dubbo.validation.support.AbstractValidation
  */
-@Activate(group = {Constants.CONSUMER, Constants.PROVIDER}, value = Constants.VALIDATION_KEY, order = 10000)
+@Activate(group = {CommonConstants.CONSUMER, CommonConstants.PROVIDER}, value = Constants.VALIDATION_KEY, order = 10000)
 public class ValidationFilter implements Filter {
 
     private Validation validation;

dubbo-metadata-report/dubbo-metadata-report-api/src/main/java/org/apache/dubbo/metadata/identifier/MetadataIdentifier.java

@@ -16,9 +16,15 @@
  */
 package org.apache.dubbo.metadata.identifier;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 
+import static org.apache.dubbo.common.constants.CommonConstants.ANY_VALUE;
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * 2018/10/25
  */
@@ -47,15 +53,15 @@ public class MetadataIdentifier {
 
     public MetadataIdentifier(URL url) {
         this.serviceInterface = url.getServiceInterface();
-        this.version = url.getParameter(Constants.VERSION_KEY);
-        this.group = url.getParameter(Constants.GROUP_KEY);
-        this.side = url.getParameter(Constants.SIDE_KEY);
-        setApplication(url.getParameter(Constants.APPLICATION_KEY));
+        this.version = url.getParameter(VERSION_KEY);
+        this.group = url.getParameter(GROUP_KEY);
+        this.side = url.getParameter(SIDE_KEY);
+        setApplication(url.getParameter(APPLICATION_KEY));
     }
 
     public String getUniqueKey(KeyTypeEnum keyType) {
         if (keyType == KeyTypeEnum.PATH) {
-            return getFilePathKey() + Constants.PATH_SEPARATOR + DEFAULT_PATH_TAG;
+            return getFilePathKey() + PATH_SEPARATOR + DEFAULT_PATH_TAG;
         }
         return getIdentifierKey() + META_DATA_STORE_TAG;
     }
@@ -69,12 +75,12 @@ public class MetadataIdentifier {
     }
 
     private String getFilePathKey(String pathTag) {
-        return pathTag + Constants.PATH_SEPARATOR + toServicePath() + Constants.PATH_SEPARATOR + (version == null ? "" : (version + Constants.PATH_SEPARATOR))
-                + (group == null ? "" : (group + Constants.PATH_SEPARATOR)) + side + Constants.PATH_SEPARATOR + getApplication();
+        return pathTag + PATH_SEPARATOR + toServicePath() + PATH_SEPARATOR + (version == null ? "" : (version + PATH_SEPARATOR))
+                + (group == null ? "" : (group + PATH_SEPARATOR)) + side + PATH_SEPARATOR + getApplication();
     }
 
     private String toServicePath() {
-        if (Constants.ANY_VALUE.equals(serviceInterface)) {
+        if (ANY_VALUE.equals(serviceInterface)) {
             return "";
         }
         return URL.encode(serviceInterface);

dubbo-metadata-report/dubbo-metadata-report-api/src/main/java/org/apache/dubbo/metadata/integration/MetadataReportService.java

@@ -33,6 +33,16 @@ import org.apache.dubbo.rpc.RpcException;
 
 import java.util.function.Supplier;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_DIRECTORY;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PID_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMESTAMP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * @since 2.7.0
  */
@@ -49,7 +59,7 @@ public class MetadataReportService {
 
     MetadataReportService(URL metadataReportURL) {
         if (Constants.METADATA_REPORT_KEY.equals(metadataReportURL.getProtocol())) {
-            String protocol = metadataReportURL.getParameter(Constants.METADATA_REPORT_KEY, Constants.DEFAULT_DIRECTORY);
+            String protocol = metadataReportURL.getParameter(Constants.METADATA_REPORT_KEY, DEFAULT_DIRECTORY);
             metadataReportURL = URLBuilder.from(metadataReportURL)
                     .setProtocol(protocol)
                     .removeParameter(Constants.METADATA_REPORT_KEY)
@@ -79,16 +89,16 @@ public class MetadataReportService {
     public void publishProvider(URL providerUrl) throws RpcException {
         //first add into the list
         // remove the individul param
-        providerUrl = providerUrl.removeParameters(Constants.PID_KEY, Constants.TIMESTAMP_KEY, RemotingConstants.BIND_IP_KEY, RemotingConstants.BIND_PORT_KEY, Constants.TIMESTAMP_KEY);
+        providerUrl = providerUrl.removeParameters(PID_KEY, TIMESTAMP_KEY, RemotingConstants.BIND_IP_KEY, RemotingConstants.BIND_PORT_KEY, TIMESTAMP_KEY);
 
         try {
-            String interfaceName = providerUrl.getParameter(Constants.INTERFACE_KEY);
+            String interfaceName = providerUrl.getParameter(INTERFACE_KEY);
             if (StringUtils.isNotEmpty(interfaceName)) {
                 Class interfaceClass = Class.forName(interfaceName);
                 FullServiceDefinition fullServiceDefinition = ServiceDefinitionBuilder.buildFullDefinition(interfaceClass, providerUrl.getParameters());
                 metadataReport.storeProviderMetadata(new MetadataIdentifier(providerUrl.getServiceInterface(),
-                        providerUrl.getParameter(Constants.VERSION_KEY), providerUrl.getParameter(Constants.GROUP_KEY),
-                        Constants.PROVIDER_SIDE,providerUrl.getParameter(Constants.APPLICATION_KEY)), fullServiceDefinition);
+                        providerUrl.getParameter(VERSION_KEY), providerUrl.getParameter(GROUP_KEY),
+                        PROVIDER_SIDE, providerUrl.getParameter(APPLICATION_KEY)), fullServiceDefinition);
                 return;
             }
             logger.error("publishProvider interfaceName is empty . providerUrl: " + providerUrl.toFullString());
@@ -99,10 +109,10 @@ public class MetadataReportService {
     }
 
     public void publishConsumer(URL consumerURL) throws RpcException {
-        consumerURL = consumerURL.removeParameters(Constants.PID_KEY, Constants.TIMESTAMP_KEY, RemotingConstants.BIND_IP_KEY, RemotingConstants.BIND_PORT_KEY, Constants.TIMESTAMP_KEY);
+        consumerURL = consumerURL.removeParameters(PID_KEY, TIMESTAMP_KEY, RemotingConstants.BIND_IP_KEY, RemotingConstants.BIND_PORT_KEY, TIMESTAMP_KEY);
         metadataReport.storeConsumerMetadata(new MetadataIdentifier(consumerURL.getServiceInterface(),
-                consumerURL.getParameter(Constants.VERSION_KEY), consumerURL.getParameter(Constants.GROUP_KEY),Constants.CONSUMER_SIDE,
-                consumerURL.getParameter(Constants.APPLICATION_KEY)), consumerURL.getParameters());
+                consumerURL.getParameter(VERSION_KEY), consumerURL.getParameter(GROUP_KEY), CONSUMER_SIDE,
+                consumerURL.getParameter(APPLICATION_KEY)), consumerURL.getParameters());
     }
 
 }

dubbo-metadata-report/dubbo-metadata-report-api/src/main/java/org/apache/dubbo/metadata/support/AbstractMetadataReport.java

@@ -51,6 +51,12 @@ import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.FILE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
+
 /**
  *
  */
@@ -80,7 +86,7 @@ public abstract class AbstractMetadataReport implements MetadataReport {
     public AbstractMetadataReport(URL reportServerURL) {
         setUrl(reportServerURL);
         // Start file save timer
-        String filename = reportServerURL.getParameter(Constants.FILE_KEY, System.getProperty("user.home") + "/.dubbo/dubbo-metadata-" + reportServerURL.getParameter(Constants.APPLICATION_KEY) + "-" + reportServerURL.getAddress() + ".cache");
+        String filename = reportServerURL.getParameter(FILE_KEY, System.getProperty("user.home") + "/.dubbo/dubbo-metadata-" + reportServerURL.getParameter(APPLICATION_KEY) + "-" + reportServerURL.getAddress() + ".cache");
         File file = null;
         if (ConfigUtils.isNotEmpty(filename)) {
             file = new File(filename);
@@ -271,7 +277,7 @@ public abstract class AbstractMetadataReport implements MetadataReport {
 
 
     String getProtocol(URL url) {
-        String protocol = url.getParameter(Constants.SIDE_KEY);
+        String protocol = url.getParameter(SIDE_KEY);
         protocol = protocol == null ? url.getProtocol() : protocol;
         return protocol;
     }
@@ -290,9 +296,9 @@ public abstract class AbstractMetadataReport implements MetadataReport {
         Iterator<Map.Entry<MetadataIdentifier, Object>> iterable = metadataMap.entrySet().iterator();
         while (iterable.hasNext()) {
             Map.Entry<MetadataIdentifier, Object> item = iterable.next();
-            if (Constants.PROVIDER_SIDE.equals(item.getKey().getSide())) {
+            if (PROVIDER_SIDE.equals(item.getKey().getSide())) {
                 this.storeProviderMetadata(item.getKey(), (FullServiceDefinition) item.getValue());
-            } else if (Constants.CONSUMER_SIDE.equals(item.getKey().getSide())) {
+            } else if (CONSUMER_SIDE.equals(item.getKey().getSide())) {
                 this.storeConsumerMetadata(item.getKey(), (Map) item.getValue());
             }
 

dubbo-metadata-report/dubbo-metadata-report-api/src/test/java/org/apache/dubbo/metadata/identifier/MetadataIdentifierTest.java

@@ -16,11 +16,11 @@
  */
 package org.apache.dubbo.metadata.identifier;
 
-import org.apache.dubbo.common.Constants;
-
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
 import static org.apache.dubbo.metadata.identifier.MetadataIdentifier.META_DATA_STORE_TAG;
 
 /**
@@ -34,18 +34,18 @@ public class MetadataIdentifierTest {
         String version = "1.0.0.zk.md";
         String group = null;
         String application = "vic.zk.md";
-        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.PROVIDER_SIDE, application);
+        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, PROVIDER_SIDE, application);
         System.out.println(providerMetadataIdentifier.getUniqueKey(MetadataIdentifier.KeyTypeEnum.PATH));
         Assertions.assertEquals(providerMetadataIdentifier.getUniqueKey(MetadataIdentifier.KeyTypeEnum.PATH),
-                "metadata" + Constants.PATH_SEPARATOR + interfaceName + Constants.PATH_SEPARATOR +
-                        (version == null ? "" : (version + Constants.PATH_SEPARATOR))
-                + (group == null ? "" : (group + Constants.PATH_SEPARATOR)) + Constants.PROVIDER_SIDE
-                        + Constants.PATH_SEPARATOR + application + Constants.PATH_SEPARATOR + "metadata");
+                "metadata" + PATH_SEPARATOR + interfaceName + PATH_SEPARATOR +
+                        (version == null ? "" : (version + PATH_SEPARATOR))
+                + (group == null ? "" : (group + PATH_SEPARATOR)) + PROVIDER_SIDE
+                        + PATH_SEPARATOR + application + PATH_SEPARATOR + "metadata");
         System.out.println(providerMetadataIdentifier.getUniqueKey(MetadataIdentifier.KeyTypeEnum.UNIQUE_KEY));
         Assertions.assertEquals(providerMetadataIdentifier.getUniqueKey(MetadataIdentifier.KeyTypeEnum.UNIQUE_KEY),
                 interfaceName + MetadataIdentifier.SEPARATOR +
                         (version == null ? "" : version + MetadataIdentifier.SEPARATOR)
                         + (group == null ? "" : group + MetadataIdentifier.SEPARATOR)
-                        + Constants.PROVIDER_SIDE + MetadataIdentifier.SEPARATOR + application + META_DATA_STORE_TAG);
+                        + PROVIDER_SIDE + MetadataIdentifier.SEPARATOR + application + META_DATA_STORE_TAG);
     }
 }

dubbo-metadata-report/dubbo-metadata-report-api/src/test/java/org/apache/dubbo/metadata/store/test/JTestMetadataReport4Test.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.metadata.store.test;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -26,6 +25,8 @@ import org.apache.dubbo.metadata.support.AbstractMetadataReport;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
+
 /**
  * ZookeeperRegistry
  */
@@ -42,7 +43,7 @@ public class JTestMetadataReport4Test extends AbstractMetadataReport {
 
 
     private static String getProtocol(URL url) {
-        String protocol = url.getParameter(Constants.SIDE_KEY);
+        String protocol = url.getParameter(SIDE_KEY);
         protocol = protocol == null ? url.getProtocol() : protocol;
         return protocol;
     }

dubbo-metadata-report/dubbo-metadata-report-api/src/test/java/org/apache/dubbo/metadata/support/AbstractMetadataReportTest.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.metadata.support;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.NetUtils;
 import org.apache.dubbo.metadata.definition.ServiceDefinitionBuilder;
@@ -34,6 +33,9 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
+
 /**
  *
  */
@@ -155,7 +157,7 @@ public class AbstractMetadataReportTest {
         URL url = URL.valueOf("xxx://" + NetUtils.getLocalAddress().getHostName() + ":4444/" + interfaceName + "?version=" + version + "&application="
                 + application + (group == null ? "" : "&group=" + group) + "&testPKey=8989");
 
-        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.PROVIDER_SIDE,application);
+        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, PROVIDER_SIDE,application);
         Class interfaceClass = Class.forName(interfaceName);
         FullServiceDefinition fullServiceDefinition = ServiceDefinitionBuilder.buildFullDefinition(interfaceClass, url.getParameters());
 
@@ -169,7 +171,7 @@ public class AbstractMetadataReportTest {
                 + application + (group == null ? "" : "&group=" + group) + "&testPKey=9090");
 
         tmp.putAll(url.getParameters());
-        MetadataIdentifier consumerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.CONSUMER_SIDE, application);
+        MetadataIdentifier consumerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, CONSUMER_SIDE, application);
 
         abstractMetadataReport.storeConsumerMetadata(consumerMetadataIdentifier, tmp);
 

dubbo-metadata-report/dubbo-metadata-report-etcd/src/main/java/org/apache/dubbo/metadata/store/etcd/EtcdMetadataReport.java

@@ -33,7 +33,6 @@
  */
 package org.apache.dubbo.metadata.store.etcd;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -41,6 +40,9 @@ import org.apache.dubbo.metadata.identifier.MetadataIdentifier;
 import org.apache.dubbo.metadata.support.AbstractMetadataReport;
 import org.apache.dubbo.remoting.etcd.jetcd.JEtcdClient;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
+
 /**
  * Report Metadata to Etcd
  */
@@ -60,9 +62,9 @@ public class EtcdMetadataReport extends AbstractMetadataReport {
         if (url.isAnyHost()) {
             throw new IllegalStateException("registry address == null");
         }
-        String group = url.getParameter(Constants.GROUP_KEY, DEFAULT_ROOT);
-        if (!group.startsWith(Constants.PATH_SEPARATOR)) {
-            group = Constants.PATH_SEPARATOR + group;
+        String group = url.getParameter(GROUP_KEY, DEFAULT_ROOT);
+        if (!group.startsWith(PATH_SEPARATOR)) {
+            group = PATH_SEPARATOR + group;
         }
         this.root = group;
         etcdClient = new JEtcdClient(url);
@@ -90,9 +92,9 @@ public class EtcdMetadataReport extends AbstractMetadataReport {
     }
 
     String toRootDir() {
-        if (root.equals(Constants.PATH_SEPARATOR)) {
+        if (root.equals(PATH_SEPARATOR)) {
             return root;
         }
-        return root + Constants.PATH_SEPARATOR;
+        return root + PATH_SEPARATOR;
     }
 }

dubbo-metadata-report/dubbo-metadata-report-etcd/src/test/java/org/apache/dubbo/metadata/store/etcd/EtcdMetadataReportTest.java

@@ -17,18 +17,18 @@
 
 package org.apache.dubbo.metadata.store.etcd;
 
+import org.apache.dubbo.common.URL;
+import org.apache.dubbo.common.utils.NetUtils;
+import org.apache.dubbo.metadata.definition.ServiceDefinitionBuilder;
+import org.apache.dubbo.metadata.definition.model.FullServiceDefinition;
+import org.apache.dubbo.metadata.identifier.MetadataIdentifier;
+
 import com.google.gson.Gson;
 import io.etcd.jetcd.ByteSequence;
 import io.etcd.jetcd.Client;
 import io.etcd.jetcd.kv.GetResponse;
 import io.etcd.jetcd.launcher.EtcdCluster;
 import io.etcd.jetcd.launcher.EtcdClusterFactory;
-import org.apache.dubbo.common.Constants;
-import org.apache.dubbo.common.URL;
-import org.apache.dubbo.common.utils.NetUtils;
-import org.apache.dubbo.metadata.definition.ServiceDefinitionBuilder;
-import org.apache.dubbo.metadata.definition.model.FullServiceDefinition;
-import org.apache.dubbo.metadata.identifier.MetadataIdentifier;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
@@ -41,6 +41,9 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
 
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
+
 /**
  * Unit test for etcd metadata report
  */
@@ -109,7 +112,7 @@ public class EtcdMetadataReportTest {
                 + application + (group == null ? "" : "&group=" + group));
 
         MetadataIdentifier providerMetadataIdentifier =
-                new MetadataIdentifier(interfaceName, version, group, Constants.PROVIDER_SIDE, application);
+                new MetadataIdentifier(interfaceName, version, group, PROVIDER_SIDE, application);
         Class interfaceClass = Class.forName(interfaceName);
         FullServiceDefinition fullServiceDefinition =
                 ServiceDefinitionBuilder.buildFullDefinition(interfaceClass, url.getParameters());
@@ -122,7 +125,7 @@ public class EtcdMetadataReportTest {
     private MetadataIdentifier storeConsumer(EtcdMetadataReport etcdMetadataReport, String interfaceName,
                                              String version, String group, String application) throws InterruptedException {
 
-        MetadataIdentifier consumerIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.CONSUMER_SIDE, application);
+        MetadataIdentifier consumerIdentifier = new MetadataIdentifier(interfaceName, version, group, CONSUMER_SIDE, application);
         Map<String, String> tmp = new HashMap<>();
         tmp.put("paramConsumerTest", "etcdConsumer");
         etcdMetadataReport.storeConsumerMetadata(consumerIdentifier, tmp);

dubbo-metadata-report/dubbo-metadata-report-redis/src/main/java/org/apache/dubbo/metadata/store/redis/RedisMetadataReport.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.metadata.store.redis;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -27,6 +26,9 @@ import redis.clients.jedis.Jedis;
 import redis.clients.jedis.JedisPool;
 import redis.clients.jedis.JedisPoolConfig;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_TIMEOUT;
+import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
+
 /**
  * RedisMetadataReport
  */
@@ -38,7 +40,7 @@ public class RedisMetadataReport extends AbstractMetadataReport {
 
     public RedisMetadataReport(URL url) {
         super(url);
-        int timeout = url.getParameter(Constants.TIMEOUT_KEY, Constants.DEFAULT_TIMEOUT);
+        int timeout = url.getParameter(TIMEOUT_KEY, DEFAULT_TIMEOUT);
         pool = new JedisPool(new JedisPoolConfig(), url.getHost(), url.getPort(), timeout, url.getPassword());
     }
 

dubbo-metadata-report/dubbo-metadata-report-redis/src/test/java/org/apache/dubbo/metadata/store/redis/RedisMetadataReportTest.java

@@ -16,14 +16,14 @@
  */
 package org.apache.dubbo.metadata.store.redis;
 
-import com.google.gson.Gson;
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.NetUtils;
 import org.apache.dubbo.metadata.definition.ServiceDefinitionBuilder;
 import org.apache.dubbo.metadata.definition.model.FullServiceDefinition;
 import org.apache.dubbo.metadata.identifier.MetadataIdentifier;
 import org.apache.dubbo.rpc.RpcException;
+
+import com.google.gson.Gson;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
@@ -39,6 +39,8 @@ import java.util.HashMap;
 import java.util.Map;
 
 import static org.apache.dubbo.common.Constants.SYNC_REPORT_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
 
 /**
  * 2018/10/9
@@ -153,7 +155,7 @@ public class RedisMetadataReportTest {
         URL url = URL.valueOf("xxx://" + NetUtils.getLocalAddress().getHostName() + ":4444/" + interfaceName + "?paramTest=redisTest&version=" + version + "&application="
                 + application + (group == null ? "" : "&group=" + group));
 
-        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.PROVIDER_SIDE, application);
+        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, PROVIDER_SIDE, application);
         Class interfaceClass = Class.forName(interfaceName);
         FullServiceDefinition fullServiceDefinition = ServiceDefinitionBuilder.buildFullDefinition(interfaceClass, url.getParameters());
 
@@ -170,7 +172,7 @@ public class RedisMetadataReportTest {
         URL url = URL.valueOf("xxx://" + NetUtils.getLocalAddress().getHostName() + ":4444/" + interfaceName + "?version=" + version + "&application="
                 + application + (group == null ? "" : "&group=" + group));
 
-        MetadataIdentifier consumerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.CONSUMER_SIDE, application);
+        MetadataIdentifier consumerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, CONSUMER_SIDE, application);
         Class interfaceClass = Class.forName(interfaceName);
 
         Map<String, String> tmp = new HashMap<>();

dubbo-metadata-report/dubbo-metadata-report-zookeeper/src/main/java/org/apache/dubbo/metadata/store/zookeeper/ZookeeperMetadataReport.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.metadata.store.zookeeper;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -25,6 +24,9 @@ import org.apache.dubbo.metadata.support.AbstractMetadataReport;
 import org.apache.dubbo.remoting.zookeeper.ZookeeperClient;
 import org.apache.dubbo.remoting.zookeeper.ZookeeperTransporter;
 
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
+
 /**
  * ZookeeperMetadataReport
  */
@@ -41,19 +43,19 @@ public class ZookeeperMetadataReport extends AbstractMetadataReport {
         if (url.isAnyHost()) {
             throw new IllegalStateException("registry address == null");
         }
-        String group = url.getParameter(Constants.GROUP_KEY, DEFAULT_ROOT);
-        if (!group.startsWith(Constants.PATH_SEPARATOR)) {
-            group = Constants.PATH_SEPARATOR + group;
+        String group = url.getParameter(GROUP_KEY, DEFAULT_ROOT);
+        if (!group.startsWith(PATH_SEPARATOR)) {
+            group = PATH_SEPARATOR + group;
         }
         this.root = group;
         zkClient = zookeeperTransporter.connect(url);
     }
 
     String toRootDir() {
-        if (root.equals(Constants.PATH_SEPARATOR)) {
+        if (root.equals(PATH_SEPARATOR)) {
             return root;
         }
-        return root + Constants.PATH_SEPARATOR;
+        return root + PATH_SEPARATOR;
     }
 
     @Override

dubbo-metadata-report/dubbo-metadata-report-zookeeper/src/test/java/org/apache/dubbo/metadata/store/zookeeper/ZookeeperMetadataReportTest.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.metadata.store.zookeeper;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.utils.NetUtils;
 import org.apache.dubbo.metadata.definition.ServiceDefinitionBuilder;
@@ -34,6 +33,9 @@ import org.junit.jupiter.api.Test;
 import java.util.HashMap;
 import java.util.Map;
 
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER_SIDE;
+
 /**
  * 2018/10/9
  */
@@ -122,7 +124,7 @@ public class ZookeeperMetadataReportTest {
         URL url = URL.valueOf("xxx://" + NetUtils.getLocalAddress().getHostName() + ":4444/" + interfaceName + "?paramTest=zkTest&version=" + version + "&application="
                 + application + (group == null ? "" : "&group=" + group));
 
-        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.PROVIDER_SIDE, application);
+        MetadataIdentifier providerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, PROVIDER_SIDE, application);
         Class interfaceClass = Class.forName(interfaceName);
         FullServiceDefinition fullServiceDefinition = ServiceDefinitionBuilder.buildFullDefinition(interfaceClass, url.getParameters());
 
@@ -135,7 +137,7 @@ public class ZookeeperMetadataReportTest {
         URL url = URL.valueOf("xxx://" + NetUtils.getLocalAddress().getHostName() + ":4444/" + interfaceName + "?version=" + version + "&application="
                 + application + (group == null ? "" : "&group=" + group));
 
-        MetadataIdentifier consumerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, Constants.CONSUMER_SIDE, application);
+        MetadataIdentifier consumerMetadataIdentifier = new MetadataIdentifier(interfaceName, version, group, CONSUMER_SIDE, application);
         Class interfaceClass = Class.forName(interfaceName);
 
         Map<String, String> tmp = new HashMap<>();

dubbo-monitor/dubbo-monitor-api/src/main/java/org/apache/dubbo/monitor/support/AbstractMonitorFactory.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.monitor.support;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -38,6 +37,8 @@ import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.locks.ReentrantLock;
 
+import static org.apache.dubbo.common.constants.CommonConstants.INTERFACE_KEY;
+
 /**
  * AbstractMonitorFactory. (SPI, Singleton, ThreadSafe)
  */
@@ -67,7 +68,7 @@ public abstract class AbstractMonitorFactory implements MonitorFactory {
 
     @Override
     public Monitor getMonitor(URL url) {
-        url = url.setPath(MonitorService.class.getName()).addParameter(Constants.INTERFACE_KEY, MonitorService.class.getName());
+        url = url.setPath(MonitorService.class.getName()).addParameter(INTERFACE_KEY, MonitorService.class.getName());
         String key = url.toServiceStringWithoutResolving();
         Monitor monitor = MONITORS.get(key);
         Future<Monitor> future = FUTURES.get(key);

dubbo-monitor/dubbo-monitor-api/src/main/java/org/apache/dubbo/monitor/support/MonitorFilter.java

@@ -37,10 +37,19 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ConcurrentMap;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.GROUP_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PATH_SEPARATOR;
+import static org.apache.dubbo.common.constants.CommonConstants.PROVIDER;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.VERSION_KEY;
+
 /**
  * MonitorFilter. (SPI, Singleton, ThreadSafe)
  */
-@Activate(group = {Constants.PROVIDER, Constants.CONSUMER})
+@Activate(group = {PROVIDER, CONSUMER})
 public class MonitorFilter implements Filter {
 
     private static final Logger logger = LoggerFactory.getLogger(MonitorFilter.class);
@@ -128,15 +137,15 @@ public class MonitorFilter implements Filter {
         // ---- service statistics ----
         long elapsed = System.currentTimeMillis() - start; // invocation cost
         int concurrent = getConcurrent(invoker, invocation).get(); // current concurrent count
-        String application = invoker.getUrl().getParameter(Constants.APPLICATION_KEY);
+        String application = invoker.getUrl().getParameter(APPLICATION_KEY);
         String service = invoker.getInterface().getName(); // service name
         String method = RpcUtils.getMethodName(invocation); // method name
-        String group = invoker.getUrl().getParameter(Constants.GROUP_KEY);
-        String version = invoker.getUrl().getParameter(Constants.VERSION_KEY);
+        String group = invoker.getUrl().getParameter(GROUP_KEY);
+        String version = invoker.getUrl().getParameter(VERSION_KEY);
 
         int localPort;
         String remoteKey, remoteValue;
-        if (Constants.CONSUMER_SIDE.equals(invoker.getUrl().getParameter(Constants.SIDE_KEY))) {
+        if (CONSUMER_SIDE.equals(invoker.getUrl().getParameter(SIDE_KEY))) {
             // ---- for service consumer ----
             localPort = 0;
             remoteKey = MonitorService.PROVIDER;
@@ -157,7 +166,7 @@ public class MonitorFilter implements Filter {
 
         return new URL(Constants.COUNT_PROTOCOL,
                 NetUtils.getLocalHost(), localPort,
-                service + Constants.PATH_SEPARATOR + method,
+                service + PATH_SEPARATOR + method,
                 MonitorService.APPLICATION, application,
                 MonitorService.INTERFACE, service,
                 MonitorService.METHOD, method,
@@ -167,8 +176,8 @@ public class MonitorFilter implements Filter {
                 MonitorService.CONCURRENT, String.valueOf(concurrent),
                 Constants.INPUT_KEY, input,
                 Constants.OUTPUT_KEY, output,
-                Constants.GROUP_KEY, group,
-                Constants.VERSION_KEY, version);
+                GROUP_KEY, group,
+                VERSION_KEY, version);
     }
 
     // concurrent counter

dubbo-monitor/dubbo-monitor-api/src/test/java/org/apache/dubbo/monitor/support/MonitorFilterTest.java

@@ -28,6 +28,7 @@ import org.apache.dubbo.rpc.Result;
 import org.apache.dubbo.rpc.RpcContext;
 import org.apache.dubbo.rpc.RpcException;
 import org.apache.dubbo.rpc.RpcInvocation;
+
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
@@ -37,6 +38,9 @@ import java.net.URLEncoder;
 import java.util.Arrays;
 import java.util.List;
 
+import static org.apache.dubbo.common.constants.CommonConstants.APPLICATION_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.CONSUMER_SIDE;
+import static org.apache.dubbo.common.constants.CommonConstants.SIDE_KEY;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.Mockito.mock;
@@ -60,7 +64,7 @@ public class MonitorFilterTest {
 
         public URL getUrl() {
             try {
-                return URL.valueOf("dubbo://" + NetUtils.getLocalHost() + ":20880?" + Constants.APPLICATION_KEY + "=abc&" + Constants.SIDE_KEY + "=" + Constants.CONSUMER_SIDE + "&" + Constants.MONITOR_KEY + "=" + URLEncoder.encode("dubbo://" + NetUtils.getLocalHost() + ":7070", "UTF-8"));
+                return URL.valueOf("dubbo://" + NetUtils.getLocalHost() + ":20880?" + APPLICATION_KEY + "=abc&" + SIDE_KEY + "=" + CONSUMER_SIDE + "&" + Constants.MONITOR_KEY + "=" + URLEncoder.encode("dubbo://" + NetUtils.getLocalHost() + ":7070", "UTF-8"));
             } catch (UnsupportedEncodingException e) {
                 throw new IllegalStateException(e.getMessage(), e);
             }
@@ -138,7 +142,7 @@ public class MonitorFilterTest {
         monitorFilter.setMonitorFactory(mockMonitorFactory);
         Invocation invocation = new RpcInvocation("aaa", new Class<?>[0], new Object[0]);
         Invoker invoker = mock(Invoker.class);
-        given(invoker.getUrl()).willReturn(URL.valueOf("dubbo://" + NetUtils.getLocalHost() + ":20880?" + Constants.APPLICATION_KEY + "=abc&" + Constants.SIDE_KEY + "=" + Constants.CONSUMER_SIDE));
+        given(invoker.getUrl()).willReturn(URL.valueOf("dubbo://" + NetUtils.getLocalHost() + ":20880?" + APPLICATION_KEY + "=abc&" + SIDE_KEY + "=" + CONSUMER_SIDE));
 
         monitorFilter.invoke(invoker, invocation);
 

dubbo-monitor/dubbo-monitor-default/src/main/java/org/apache/dubbo/monitor/dubbo/DubboMonitor.java

@@ -16,7 +16,6 @@
  */
 package org.apache.dubbo.monitor.dubbo;
 
-import org.apache.dubbo.common.Constants;
 import org.apache.dubbo.common.URL;
 import org.apache.dubbo.common.logger.Logger;
 import org.apache.dubbo.common.logger.LoggerFactory;
@@ -36,6 +35,8 @@ import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicReference;
 
+import static org.apache.dubbo.common.constants.CommonConstants.DEFAULT_PROTOCOL;
+
 /**
  * DubboMonitor
  */
@@ -102,7 +103,7 @@ public class DubboMonitor implements Monitor {
             long maxOutput = numbers[7];
             long maxElapsed = numbers[8];
             long maxConcurrent = numbers[9];
-            String protocol = getUrl().getParameter(Constants.DEFAULT_PROTOCOL);
+            String protocol = getUrl().getParameter(DEFAULT_PROTOCOL);
 
             // send statistics data
             URL url = statistics.getUrl()
@@ -117,7 +118,7 @@ public class DubboMonitor implements Monitor {
                             MonitorService.MAX_OUTPUT, String.valueOf(maxOutput),
                             MonitorService.MAX_ELAPSED, String.valueOf(maxElapsed),
                             MonitorService.MAX_CONCURRENT, String.valueOf(maxConcurrent),
-                            Constants.DEFAULT_PROTOCOL, protocol
+                            DEFAULT_PROTOCOL, protocol
                     );
             monitorService.collect(url);
 

dubbo-monitor/dubbo-monitor-default/src/main/java/org/apache/dubbo/monitor/dubbo/DubboMonitorFactory.java

@@ -28,8 +28,8 @@ import org.apache.dubbo.rpc.ProxyFactory;
 
 import static org.apache.dubbo.common.constants.RemotingConstants.CHECK_KEY;
 import static org.apache.dubbo.common.Constants.DUBBO_PROTOCOL;
-import static org.apache.dubbo.common.Constants.PROTOCOL_KEY;
 import static org.apache.dubbo.common.Constants.REFERENCE_FILTER_KEY;
+import static org.apache.dubbo.common.constants.CommonConstants.PROTOCOL_KEY;
 
 /**
  * DefaultMonitorFactory