SLF4JPlatformLogger.isLoggable should handle Logger.ALL and Logger.OFF in a coherent fashion

relates to https://github.com/qos-ch/slf4j/issues/430

Signed-off-by: ceki <ceki@qos.ch>

AGENTS.md

@@ -0,0 +1,22 @@
+
+# Agent Rules
+
+**Never commit or push changes.**
+
+### Strict Rules:
+
+- Do not run `git commit`, `git push`, `git add`, or any git command
+  that modifies the repository history.
+
+- You may edit files multiple times in one session.
+
+- You may run tests, build commands, invoke linters to validate
+  changes or check your work as needed.
+
+- If you believe a commit or any other git action is needed, ask me
+  first.
+
+- The code is widely used. Thus, any changes must preserve backward
+  compatibility, especially changes in interfaces or super classes.
+
+Follow these rules at all times.

integration/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 

integration/src/test/java/org/slf4j/MultiBindingAssertionTest.java

@@ -61,7 +61,6 @@ public class MultiBindingAssertionTest {
         assertMsgContains(list, line++, "Found provider");
         assertMsgContains(list, line++, "Found provider");
         assertMsgContains(list, line++, "See https://www.slf4j.org/codes.html#multiple_bindings for an explanation.");
-        //assertMsgContains(list, line++, "SLF4J(D): Connected with provider of type [");
     }
 
     void assertMsgContains(List<String> strList, int index, String msg) {

jcl-over-slf4j-blackbox/pom.xml

@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+  <parent>
+    <groupId>org.slf4j</groupId>
+    <artifactId>slf4j-parent</artifactId>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
+    <relativePath>../parent/pom.xml</relativePath>
+  </parent>
+
+  <modelVersion>4.0.0</modelVersion>
+
+  <artifactId>jcl-over-slf4j-blackbox</artifactId>
+  <packaging>jar</packaging>
+  <name>jcl-over-slf4j blackbox testing</name>
+  <description>jcl-over-slf4j blackbox testing</description>
+  <url>http://www.slf4j.org</url>
+
+  <licenses>
+    <license>
+      <name>Apache License, Version 2.0</name>
+      <url>https://www.apache.org/licenses/LICENSE-2.0.txt</url>
+      <distribution>repo</distribution>
+    </license>
+  </licenses>
+
+  <properties>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>jcl-over-slf4j</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>${junit.version}</version>
+      <scope>compile</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-jdk14</artifactId>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-deploy-plugin</artifactId>
+        <configuration>
+          <skip>true</skip>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+
+</project>

jcl-over-slf4j-blackbox/src/main/java/module-info.java

@@ -0,0 +1,7 @@
+module org.apache.commons.logging.blackbox {
+    requires org.slf4j;
+    requires org.slf4j.jul;
+    requires org.apache.commons.logging;
+    requires java.logging;
+    requires junit;
+}

jcl-over-slf4j-blackbox/src/main/java/org/apache/commons/logging/blackbox/SerializationTest.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.apache.commons.logging.test;
+package org.apache.commons.logging.blackbox;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -36,6 +36,7 @@ import org.apache.commons.logging.impl.SLF4JLocationAwareLog;
 import org.apache.commons.logging.impl.SLF4JLog;
 import org.junit.After;
 import org.junit.Before;
+import org.junit.Ignore;
 import org.junit.Test;
 import org.slf4j.jul.JDK14LoggerFactory;
 import org.slf4j.spi.LocationAwareLogger;

jcl-over-slf4j/pom.xml

@@ -5,7 +5,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -14,7 +14,7 @@
   <artifactId>jcl-over-slf4j</artifactId>
   <packaging>jar</packaging>
   <name>JCL 1.2 implemented over SLF4J</name>
-  <description>JCL 1.2 implemented over SLF4J</description>
+  <description>Jakarta/Apache commons logging 1.2 implemented over SLF4J</description>
   <url>http://www.slf4j.org</url>
 
   <licenses>

jcl-over-slf4j/src/main/java/module-info.java

@@ -0,0 +1,8 @@
+/**
+ * Jakarta/Apache Commons Logging implemented over SLF4J.
+ */
+module org.apache.commons.logging {
+  requires org.slf4j;
+  exports org.apache.commons.logging;
+  exports org.apache.commons.logging.impl;
+}

jcl-over-slf4j/src/main/java/org/apache/commons/logging/package-info.java

@@ -0,0 +1,151 @@
+/**
+ * <p>Jakarta Commons Logging implemented over SLF4J.</p>
+ *
+ *
+ * <h3>Overview</h3>
+ *
+ * <p>This package contains the same public user interface as <a
+ * href="http://jakarta.apache.org/commons/logging/">Jakarta Commons
+ * Logging (JCL)</a>. <b>It is intended as a 100% compatible drop-in
+ * replacement for the original JCL version 1.0.4</b>.
+ * </p>
+ *
+ * <p>As the original JCL version 1.0.4, the present version supports
+ * various logging APIs. It differs from the original in implementation
+ * but not the public API. This implementation uses SLF4J under the
+ * covers. As such, all the logging systems that SLF4J supports,
+ * e.g. NOP, Simple, logback, java.util.logging, log4j 1.x are supported 
+ * indirectly by this version of JCL via SLF4J.
+ * </p>
+ *
+ * <h3>Quick Start Guide</h3>
+ *
+ * <p>For those impatient to just get on with it, the following example
+ * illustrates the typical declaration and use of a logger that is named (by
+ * convention) after the calling class:
+ *
+ * <pre>
+ *  import org.apache.commons.logging.Log;
+ *  import org.apache.commons.logging.LogFactory;
+ *
+ *  public class Foo {
+ *
+ *    static Log log = LogFactory.getLog(Foo.class);
+ *
+ *    public void foo() {
+ *      ...
+ *      try {
+ *        if (log.isDebugEnabled()) {
+ *          log.debug("About to do something to object " + name);
+ *        }
+ *        name.bar();
+ *      } catch (IllegalStateException e) {
+ *        log.error("Something bad happened to " + name, e);
+ *      }
+ *      ...
+ *    }
+ * </pre>
+ *
+ * <h3>Configuring the Commons Logging Package</h3>
+ *
+ * <p>In this version of JCL, the selection of the logging system to use
+ * is chosen by SLF4J at initialization time. Consequently, all JCL-specific
+ * configuration parameters are ignored.
+ * </p>
+ *
+ * <h4>Choosing a <code>LogFactory</code> Implementation</h4>
+ *
+ * <p>From an application perspective, the first requirement is to
+ * retrieve an object reference to the <code>LogFactory</code> instance
+ * that will be used to create <code><a href="Log.html">Log</a></code>
+ * instances for this application.  This is normally accomplished by
+ * calling the static <code>getFactory()</code> method.  This method
+ * always returns the same factory, i.e. a unique instance of the <a
+ * href="impl/SLF4FLogFactory.html">SLF4FLogFactory</a> class.
+ * </p>
+ *
+ *
+ *
+ * <h4>Configuring the Underlying Logging System</h4>
+ *
+ * <p>The basic principle is that the user is totally responsible for the
+ * configuration of the underlying logging system.
+ * Commons-logging should not change the existing configuration.</p>
+ *
+ * <p>Each individual <a href="Log.html">Log</a> implementation may
+ * support its own configuration properties.  These will be documented in the
+ * class descriptions for the corresponding implementation class.</p>
+ *
+ * <p>Finally, some <code>Log</code> implementations (such logback or log4j)
+ * require an external configuration file for the entire logging environment.
+ * This file should be prepared in a manner that is specific to the actual logging
+ * technology being used.</p>
+ *
+ *
+ * <h3>Using the Logging Package APIs</h3>
+ *
+ * <p>Use of the Logging Package APIs, from the perspective of an application
+ * component, consists of the following steps:</p>
+ * <ol>
+ * <li>Acquire a reference to an instance of
+ *     <a href="Log.html">org.apache.commons.logging.Log</a>, by calling the
+ *     factory method
+ *     <a href="LogFactory.html#getInstance(java.lang.String)">
+ *     LogFactory.getInstance(String name)</a>.  Your application can contain
+ *     references to multiple loggers that are used for different
+ *     purposes.  A typical scenario for a server application is to have each
+ *     major component of the server use its own Log instance.</li>
+ * <li>Cause messages to be logged (if the corresponding detail level is enabled)
+ *     by calling appropriate methods (<code>trace()</code>, <code>debug()</code>,
+ *     <code>info()</code>, <code>warn()</code>, <code>error</code>, and
+ *     <code>fatal()</code>).</li>
+ * </ol>
+ *
+ * <p>For convenience, <code>LogFactory</code> also offers a static method
+ * <code>getLog()</code> that combines the typical two-step pattern:</p>
+ * <pre>
+ *   Log log = LogFactory.getFactory().getInstance(Foo.class);
+ * </pre>
+ * <p>into a single method call:</p>
+ * <pre>
+ *   Log log = LogFactory.getLog(Foo.class);
+ * </pre>
+ *
+ * <p>For example, you might use the following technique to initialize and
+ * use a <a href="Log.html">Log</a> instance in an application component:</p>
+ * <pre>
+ * import org.apache.commons.logging.Log;
+ * import org.apache.commons.logging.LogFactory;
+ *
+ * public class MyComponent {
+ *
+ *   protected static Log log =
+ *     LogFactory.getLog(MyComponent.class);
+ *
+ *   // Called once at startup time
+ *   public void start() {
+ *     ...
+ *     log.info("MyComponent started");
+ *     ...
+ *   }
+ *
+ *   // Called once at shutdown time
+ *   public void stop() {
+ *     ...
+ *     log.info("MyComponent stopped");
+ *     ...
+ *   }
+ *
+ *   // Called repeatedly to process a particular argument value
+ *   // which you want logged if debugging is enabled
+ *   public void process(String value) {
+ *     ...
+ *     // Do the string concatenation only if logging is enabled
+ *     if (log.isDebugEnabled())
+ *       log.debug("MyComponent processing " + value);
+ *     ...
+ *   }
+ * }
+ *
+ */
+package org.apache.commons.logging;

jcl-over-slf4j/src/main/java/org/apache/commons/logging/package.html

@@ -1,169 +0,0 @@
-<!--
-
- Copyright 2001-2004 The Apache Software Foundation.
- 
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
- 
-      http://www.apache.org/licenses/LICENSE-2.0
- 
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
-
--->
-
-<body>
-<p>Jakarta Commons Logging implemented over SLF4J.</p>
-
-
-<h3>Overview</h3>
-
-<p>This package contains the same public user interface as <a
-href="http://jakarta.apache.org/commons/logging/">Jakarta Commons
-Logging (JCL)</a>. It is intended as a 100% compatible drop-in
-replacement for the original JCL version 1.0.4.
-</p>
-
-<p>As the original JCL version 1.0.4, the present version supports
-various logging APIs. It differs from the original in implementation
-but not the public API. This implementation uses SLF4J under the
-covers. As such, all the logging systems that SLF4J supports,
-e.g. NOP, Simple, JDK14, nlog4j are supported by this version of JCL.
-</p>
-
-<h3>Quick Start Guide</h3>
-
-<p>For those impatient to just get on with it, the following example
-illustrates the typical declaration and use of a logger that is named (by
-convention) after the calling class:
-
-<pre>
-    import org.apache.commons.logging.Log;
-    import org.apache.commons.logging.LogFactory;
-
-    public class Foo {
-
-        static Log log = LogFactory.getLog(Foo.class);
-
-        public void foo() {
-            ...
-            try {
-                if (log.isDebugEnabled()) {
-                    log.debug("About to do something to object " + name);
-                }
-                name.bar();
-            } catch (IllegalStateException e) {
-                log.error("Something bad happened to " + name, e);
-            }
-            ...
-        }
-</pre>
-
-<h3>Configuring the Commons Logging Package</h3>
-
-<p>In this version of JCL, the selection of the logging system to use
-is chosen by the underlying SLF4J API. Consequently, all JCL-specific
-configuration parameters are ignored.
-</p>
-
-<h4>Choosing a <code>LogFactory</code> Implementation</h4>
-
-<p>From an application perspective, the first requirement is to
-retrieve an object reference to the <code>LogFactory</code> instance
-that will be used to create <code><a href="Log.html">Log</a></code>
-instances for this application.  This is normally accomplished by
-calling the static <code>getFactory()</code> method.  This method
-always returns the same factory, i.e. a unique instance of the <a
-href="impl/SLF4FLogFactory.html">SLF4FLogFactory</a> class.
-</p>
-
-
-
-<h4>Configuring the Underlying Logging System</h4>
-
-<p>The basic principle is that the user is totally responsible for the
-configuration of the underlying logging system.
-Commons-logging should not change the existing configuration.</p>
-
-<p>Each individual <a href="Log.html">Log</a> implementation may
-support its own configuration properties.  These will be documented in the
-class descriptions for the corresponding implementation class.</p>
-
-<p>Finally, some <code>Log</code> implementations (such as the one for Log4J)
-require an external configuration file for the entire logging environment.
-This file should be prepared in a manner that is specific to the actual logging
-technology being used.</p>
-
-
-<h3>Using the Logging Package APIs</h3>
-
-<p>Use of the Logging Package APIs, from the perspective of an application
-component, consists of the following steps:</p>
-<ol>
-<li>Acquire a reference to an instance of
-    <a href="Log.html">org.apache.commons.logging.Log</a>, by calling the
-    factory method
-    <a href="LogFactory.html#getInstance(java.lang.String)">
-    LogFactory.getInstance(String name)</a>.  Your application can contain
-    references to multiple loggers that are used for different
-    purposes.  A typical scenario for a server application is to have each
-    major component of the server use its own Log instance.</li>
-<li>Cause messages to be logged (if the corresponding detail level is enabled)
-    by calling appropriate methods (<code>trace()</code>, <code>debug()</code>,
-    <code>info()</code>, <code>warn()</code>, <code>error</code>, and
-    <code>fatal()</code>).</li>
-</ol>
-
-<p>For convenience, <code>LogFactory</code> also offers a static method
-<code>getLog()</code> that combines the typical two-step pattern:</p>
-<pre>
-  Log log = LogFactory.getFactory().getInstance(Foo.class);
-</pre>
-<p>into a single method call:</p>
-<pre>
-  Log log = LogFactory.getLog(Foo.class);
-</pre>
-
-<p>For example, you might use the following technique to initialize and
-use a <a href="Log.html">Log</a> instance in an application component:</p>
-<pre>
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
-public class MyComponent {
-
-  protected static Log log =
-    LogFactory.getLog(MyComponent.class);
-
-  // Called once at startup time
-  public void start() {
-    ...
-    log.info("MyComponent started");
-    ...
-  }
-
-  // Called once at shutdown time
-  public void stop() {
-    ...
-    log.info("MyComponent stopped");
-    ...
-  }
-
-  // Called repeatedly to process a particular argument value
-  // which you want logged if debugging is enabled
-  public void process(String value) {
-    ...
-    // Do the string concatenation only if logging is enabled
-    if (log.isDebugEnabled())
-      log.debug("MyComponent processing " + value);
-    ...
-  }
-
-}
-</pre>
-
-</body>

jcl-over-slf4j/src/main/java9/module-info.java

@@ -1,4 +0,0 @@
-module org.apache.commons.logging {
-  requires org.slf4j;
-  exports org.apache.commons.logging;
-}

jul-to-slf4j-blackbox/pom.xml

@@ -0,0 +1,68 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+  <parent>
+    <groupId>org.slf4j</groupId>
+    <artifactId>slf4j-parent</artifactId>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
+    <relativePath>../parent/pom.xml</relativePath>
+  </parent>
+
+  <modelVersion>4.0.0</modelVersion>
+
+  <artifactId>jul-to-slf4j-blackbox</artifactId>
+  <packaging>jar</packaging>
+  <name>jul-to-slf4j blackbox testing</name>
+  <description>jul-to-slf4j blackbox testing</description>
+  <url>http://www.slf4j.org</url>
+
+  <licenses>
+    <license>
+      <name>Apache License, Version 2.0</name>
+      <url>https://www.apache.org/licenses/LICENSE-2.0.txt</url>
+      <distribution>repo</distribution>
+    </license>
+  </licenses>
+
+  <properties>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>jul-to-slf4j</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>${junit.version}</version>
+      <scope>compile</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-reload4j</artifactId>
+    </dependency>
+
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-deploy-plugin</artifactId>
+        <configuration>
+          <skip>true</skip>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+
+</project>

jul-to-slf4j-blackbox/src/main/java/module-info.java

@@ -0,0 +1,8 @@
+module jul.to.slf4j.blackbox {
+    requires  jul.to.slf4j;
+    requires ch.qos.reload4j;
+    requires junit;
+    requires java.logging;
+    requires org.slf4j;
+}
+

jul-to-slf4j-blackbox/src/main/java/org/slf4j/bridge/blackbox/ListAppender.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.slf4j.bridge;
+package org.slf4j.bridge.blackbox;
 
 import java.util.ArrayList;
 import java.util.List;

jul-to-slf4j-blackbox/src/main/java/org/slf4j/bridge/blackbox/SLF4JBridgeHandlerPerfTest.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.slf4j.bridge;
+package org.slf4j.bridge.blackbox;
 
 import java.util.logging.Handler;
 import java.util.logging.LogManager;
@@ -31,8 +31,10 @@ import org.apache.log4j.FileAppender;
 import org.apache.log4j.PatternLayout;
 import org.junit.After;
 import org.junit.Before;
+import org.junit.Ignore;
 import org.junit.Test;
 import org.slf4j.LoggerFactory;
+import org.slf4j.bridge.SLF4JBridgeHandler;
 
 public class SLF4JBridgeHandlerPerfTest {
 

jul-to-slf4j-blackbox/src/main/java/org/slf4j/bridge/blackbox/SLF4JBridgeHandlerTest.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.slf4j.bridge;
+package org.slf4j.bridge.blackbox;
 
 import static org.junit.Assert.assertEquals;
 
@@ -35,6 +35,7 @@ import org.apache.log4j.spi.LoggingEvent;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+import org.slf4j.bridge.SLF4JBridgeHandler;
 
 public class SLF4JBridgeHandlerTest {
 

jul-to-slf4j/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -24,12 +24,7 @@
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>
     </dependency>
-    <dependency>
-      <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-reload4j</artifactId>
-      <version>${project.version}</version>
-      <scope>test</scope>
-    </dependency>
+
   </dependencies>
 
   <build>

jul-to-slf4j/src/main/java/module-info.java

@@ -1,3 +1,6 @@
+/**
+ * Bridge/route all JUL log records to the SLF4J API.
+ */
 module jul.to.slf4j {
 
     requires org.slf4j;

jul-to-slf4j/src/main/java/org/slf4j/bridge/SLF4JBridgeHandler.java

@@ -41,8 +41,8 @@ import org.slf4j.spi.LocationAwareLogger;
 /**
  * <p>Bridge/route all JUL log records to the SLF4J API.
  * <p>Essentially, the idea is to install on the root logger an instance of
- * <code>SLF4JBridgeHandler</code> as the sole JUL handler in the system. Subsequently, the
- * SLF4JBridgeHandler instance will redirect all JUL log records are redirected
+ * {@link SLF4JBridgeHandler} as the sole JUL handler in the system. Subsequently, the
+ * <code>SLF4JBridgeHandler</code> instance will redirect all JUL log records are redirected
  * to the SLF4J API based on the following mapping of levels:
  * 
  * <pre>
@@ -92,13 +92,10 @@ import org.slf4j.spi.LocationAwareLogger;
  *
  * <h2>As a Java 9/Jigsaw module</h2>
  * 
- * <p>Given that <b>to</b> is a reserved keyword under Java 9 within module productions, 
- * the MANIFEST.MF file in <em>jul-to-slf4j.jar</em> declares <b>jul_to_slf4j</b> as
- * its Automatic Module Name. Thus, if your application is Jigsaw modularized, the requires 
- * statement in your <em>module-info.java</em> needs to be <b>jul_to_slf4j</b> 
- * (note the two underscores).
+ * <p>As of SLF4J 2.0x, the module name for <em>jul-to-slf4j.jar</em> is
+ *  <b>jul.to.slf4j</b>. In SLF4J 1.7.x it was declared via an Automatic-Module-Name statement
+ *  as <b>jul_to_slf4j</b> (note the two underscores).
  *
- * 
  * @author Christian Stein
  * @author Joern Huxhorn
  * @author Ceki G&uuml;lc&uuml;

jul-to-slf4j/src/main/java/org/slf4j/bridge/package-info.java

@@ -0,0 +1,4 @@
+/**
+ *  Bridge/route all JUL log records to the SLF4J API.
+ */
+package org.slf4j.bridge;

jul-to-slf4j/src/main/java/org/slf4j/bridge/package.html

@@ -1,15 +0,0 @@
-<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
-
-<html> 
-  <head>
-    <title></title>
-  </head>
-
-
-  <body>
-
-    <p>Bridge/route all JUL log records to the SLF4J API.</p>
-    
-    <hr>
-  </body> 
-</html>

log4j-over-slf4j-blackbox/pom.xml

@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+  <parent>
+    <groupId>org.slf4j</groupId>
+    <artifactId>slf4j-parent</artifactId>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
+    <relativePath>../parent/pom.xml</relativePath>
+  </parent>
+
+  <modelVersion>4.0.0</modelVersion>
+
+  <artifactId>log4j-over-slf4j-blackbox</artifactId>
+  <packaging>jar</packaging>
+  <name>log4j-over-slf4j blackbox testing</name>
+  <description>log4j-over-slf4j blackbox testing</description>
+  <url>http://www.slf4j.org</url>
+
+  <licenses>
+    <license>
+      <name>Apache License, Version 2.0</name>
+      <url>https://www.apache.org/licenses/LICENSE-2.0.txt</url>
+      <distribution>repo</distribution>
+    </license>
+  </licenses>
+
+  <properties>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>log4j-over-slf4j</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>${junit.version}</version>
+      <scope>compile</scope>
+    </dependency>
+
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-jdk14</artifactId>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-deploy-plugin</artifactId>
+        <configuration>
+          <skip>true</skip>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+
+</project>

log4j-over-slf4j-blackbox/src/main/java/module-info.java

@@ -0,0 +1,6 @@
+module log4j.over.slf4j.blackbox {
+
+    requires log4j.over.slf4j;
+    requires java.logging;
+    requires junit;
+}

log4j-over-slf4j-blackbox/src/main/java/org/apache/log4j/blackbox/Bug131.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.dummy;
+package org.apache.log4j.blackbox;
 
 import static org.junit.Assert.assertEquals;
 

log4j-over-slf4j-blackbox/src/main/java/org/apache/log4j/blackbox/Bug139.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.dummy;
+package org.apache.log4j.blackbox;
 
 import static org.junit.Assert.assertEquals;
 

log4j-over-slf4j-blackbox/src/main/java/org/apache/log4j/blackbox/ListHandler.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.dummy;
+package org.apache.log4j.blackbox;
 
 import java.util.ArrayList;
 import java.util.List;

log4j-over-slf4j/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 

log4j-over-slf4j/src/main/java/module-info.java

@@ -1,4 +1,4 @@
-module log4j {
+module log4j.over.slf4j {
 	requires org.slf4j;
 	requires java.xml;
 	exports org.apache.log4j;

osgi-over-slf4j/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -53,11 +53,22 @@
             <Bundle-SymbolicName>org.slf4j.osgi-over-slf4j</Bundle-SymbolicName>
             <Bundle-Activator>org.slf4j.osgi.logservice.impl.Activator</Bundle-Activator>
             <Bundle-Category>osgi</Bundle-Category>
-            <_exportcontents combine.self="override" />
+            <_exportcontents combine.self="override"/>
           </instructions>
         </configuration>
       </plugin>
 
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <configuration>
+          <archive>
+            <manifestEntries>
+              <Automatic-Module-Name>org.slf4j.osgi.logservice</Automatic-Module-Name>
+            </manifestEntries>
+          </archive>
+        </configuration>
+      </plugin>
     </plugins>
   </build>
 

parent/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-bom</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../pom.xml</relativePath>
   </parent>
 
@@ -18,7 +18,7 @@
 
 
   <organization>
-    <name>QOS.ch</name>
+    <name>QOS.CH Sarl</name>
     <url>http://www.qos.ch</url>
   </organization>
   <inceptionYear>2005</inceptionYear>
@@ -26,29 +26,30 @@
 
   <properties>
     <!-- yyyy-MM-dd'T'HH:mm:ss'Z' -->
-    <project.build.outputTimestamp>2026-05-12T18:15:00Z</project.build.outputTimestamp>
+    <project.build.outputTimestamp>2026-08-07T12:57:07Z</project.build.outputTimestamp>
     <latest.1.version>1.7.36</latest.1.version>
     <!-- java.util.ServiceLoader requires Java 6 -->
-    <jdk.version>8</jdk.version>
+    <jdk.version>11</jdk.version>
     <maven.compiler.source>${jdk.version}</maven.compiler.source>
     <maven.compiler.target>${jdk.version}</maven.compiler.target>
+
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.build.resourceEncoding>UTF-8</project.build.resourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
     <!-- used in integration testing -->
     <cal10n.version>0.8.1</cal10n.version>
-    <reload4j.version>1.2.22</reload4j.version>
+    <reload4j.version>1.2.25</reload4j.version>
     <logback.version>1.2.10</logback.version>
     <jcl.version>1.2</jcl.version>
     <junit.version>4.13.1</junit.version>
-    <maven-site-plugin.version>3.7.1</maven-site-plugin.version>
+    <maven-site-plugin.version>3.12.1</maven-site-plugin.version>
     <maven-compiler-plugin.version>3.10.1</maven-compiler-plugin.version>
     <maven-surefire-plugin.version>3.0.0-M7</maven-surefire-plugin.version>
     <maven-javadoc-plugin.version>3.6.3</maven-javadoc-plugin.version>
     <maven-source-plugin.version>3.2.1</maven-source-plugin.version>
     <maven-deploy-plugin.version>3.0.0-M1</maven-deploy-plugin.version>
     <maven-jar-plugin.version>3.2.0</maven-jar-plugin.version>
-    <maven-jxr-plugin.version>3.1.1</maven-jxr-plugin.version>
+    <maven-jxr-plugin.version>3.3.1</maven-jxr-plugin.version>
     <maven-bundle-plugin.version>5.1.9</maven-bundle-plugin.version>
   </properties>
 
@@ -95,8 +96,10 @@
         <filtering>true</filtering>
       </resource>
 
+      <!-- Use each module's own LICENSE.txt (e.g. Apache-2.0 for jcl-over-slf4j
+           and log4j-over-slf4j) rather than the repo-root MIT LICENSE. -->
       <resource>
-        <directory>..</directory>
+        <directory>${project.basedir}</directory>
         <targetPath>META-INF</targetPath>
         <includes>
           <include>LICENSE.txt</include>
@@ -142,27 +145,9 @@
               <goal>compile</goal>
             </goals>
             <configuration>
-              <source>${jdk.version}</source>
-              <target>${jdk.version}</target>
+              <release>${jdk.version}</release>
             </configuration>
           </execution>
-
-          <execution>
-            <id>module-compile</id>
-            <phase>compile</phase>
-            <goals>
-              <goal>compile</goal>
-            </goals>
-            <configuration>
-              <release>9</release>
-              <compileSourceRoots>
-                <compileSourceRoot>${project.basedir}/src/main/java9</compileSourceRoot>
-              </compileSourceRoots>
-              <multiReleaseOutput>true</multiReleaseOutput>
-            </configuration>
-          </execution>
-
-
         </executions>
 
       </plugin>
@@ -252,21 +237,44 @@
         </executions>
       </plugin>
 
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-site-plugin</artifactId>
-        <version>${maven-site-plugin.version}</version>
-      </plugin>
+<!--      <plugin>-->
+<!--        <groupId>org.apache.maven.plugins</groupId>-->
+<!--        <artifactId>maven-javadoc-plugin</artifactId>-->
+<!--        <version>3.6.3</version>-->
+<!--        <executions>-->
+<!--          <execution>-->
+<!--            <id>default-cli</id>-->
+<!--            <goals>-->
+<!--              <goal>aggregate</goal>-->
+<!--            </goals>-->
+<!--          </execution>-->
+<!--        </executions>-->
+
+<!--        <configuration>-->
+<!--          <verbose>true</verbose>-->
+<!--          &lt;!&ndash;          <sourceFileExcludes>&ndash;&gt;-->
+<!--          &lt;!&ndash;            <sourceFileExclude>**/xmodule-info.java</sourceFileExclude>&ndash;&gt;-->
+<!--          &lt;!&ndash;          </sourceFileExcludes>&ndash;&gt;-->
+<!--          <skippedModules>-->
+<!--            slf4j-testing,slf4j-ext,log4j-over-slf4j,log4j-over-slf4j-blackbox,jul-to-slf4j-blackbox,slf4j-migrator,osgi-over-slf4j-->
+<!--          </skippedModules>-->
+<!--          <detectLinks>true</detectLinks>-->
+<!--          <doctitle>SLF4J project modules ${project.version}</doctitle>-->
+<!--          <windowtitle>SLF4J javadoc</windowtitle>-->
+<!--          <linksource>true</linksource>-->
+<!--          <additionalOptions>-->
+<!--            <additionalOption>-Xdoclint:none</additionalOption>-->
+<!--          </additionalOptions>-->
+<!--        </configuration>-->
+<!--      </plugin>-->
+
 
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-project-info-reports-plugin</artifactId>
-        <version>3.0.0</version>
-      </plugin>
     </plugins>
-
   </build>
 
+  <reporting>
+  </reporting>
+
   <profiles>
     <profile>
       <id>skipTests</id>
@@ -303,6 +311,8 @@
       </build>
     </profile>
 
+
+
     <profile>
       <id>license</id>
       <build>
@@ -365,32 +375,6 @@
       </build>
     </profile>
 
-    <!--
-    <profile>
-      <id>travis</id>
-      <activation>
-        <property>
-          <name>env.TRAVIS</name>
-          <value>true</value>
-        </property>
-      </activation>
-      <build>
-        <plugins>
-          <plugin>
-            <groupId>org.apache.maven.plugins</groupId>
-            <artifactId>maven-toolchains-plugin</artifactId>
-            <version>1.1</version>
-            <executions>
-              <execution>
-                <id>toolchain</id>
-                <phase>none</phase>
-              </execution>
-            </executions>
-          </plugin>
-        </plugins>
-      </build>
-    </profile>
-    -->
   </profiles>
 
 

pom.xml

@@ -6,11 +6,11 @@
 
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-bom</artifactId>
-  <version>2.0.18</version>
+  <version>3.0.0-alpha0-SNAPSHOT</version>
   <packaging>pom</packaging>
 
   <url>http://www.slf4j.org</url>
-
+  
   <name>SLF4J BOM</name>
   <description>SLF4J project BOM</description>
 
@@ -22,18 +22,18 @@
     </license>
   </licenses>
 
-
   <scm>
     <url>https://github.com/qos-ch/slf4j</url>
     <connection>scm:git:https://github.com/qos-ch/slf4j.git</connection>
-  </scm>
-
+  </scm>  
 
+  
   <!-- Inspired by Improving the Maven Bill of Materials (BOM) Pattern  -->
   <!-- https://www.garretwilson.com/blog/2023/06/14/improve-maven-bom-pattern -->
   <modules>
     <module>parent</module>
     <module>slf4j-api</module>
+    <module>slf4j-testing</module>
     <module>slf4j-simple</module>
     <module>slf4j-nop</module>
     <module>slf4j-jdk14</module>
@@ -42,17 +42,16 @@
     <module>slf4j-reload4j</module>
     <module>slf4j-ext</module>
     <module>jcl-over-slf4j</module>
+    <module>jcl-over-slf4j-blackbox</module>
     <module>log4j-over-slf4j</module>
+    <module>log4j-over-slf4j-blackbox</module>
     <module>jul-to-slf4j</module>
+    <module>jul-to-slf4j-blackbox</module>
     <module>osgi-over-slf4j</module>
     <module>integration</module>
     <module>slf4j-migrator</module>
   </modules>
 
-  <properties>
-      <central-publishing-maven-plugin.version>0.9.0</central-publishing-maven-plugin.version>
-  </properties>
-
   <dependencyManagement>
     <dependencies>
 
@@ -73,7 +72,7 @@
         <artifactId>slf4j-nop</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-jdk14</artifactId>
@@ -86,49 +85,49 @@
         <artifactId>slf4j-jdk-platform-logging</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-log4j12</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-reload4j</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-ext</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>jcl-over-slf4j</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>log4j-over-slf4j</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>jul-to-slf4j</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>osgi-over-slf4j</artifactId>
         <version>${project.version}</version>
       </dependency>
-
+      
 
     </dependencies>
   </dependencyManagement>
@@ -156,13 +155,21 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-javadoc-plugin</artifactId>
         <version>3.6.3</version>
+        <executions>
+          <execution>
+            <id>default-cli</id>
+            <goals>
+              <goal>aggregate</goal>
+            </goals>
+          </execution>
+        </executions>
         <configuration>
           <verbose>true</verbose>
           <skippedModules>
-             slf4j-jdk-platform-logging,slf4j-migrator,osgi-over-slf4j
+            slf4j-testing,slf4j-jdk-platform-logging,jcl-over-slf4j-blackbox,log4j-over-slf4j-blackbox,jul-to-slf4j-blackbox,slf4j-migrator,osgi-over-slf4j
           </skippedModules>
           <detectLinks>true</detectLinks>
-          <doctitle>SLF4J project modules ${project.version}</doctitle>
+          <doctitle>SLF4J project modules 2.1.0-alpha1</doctitle>
           <windowtitle>SLF4J javadoc</windowtitle>
           <bottom><![CDATA[Copyright  &copy; 2005-{currentYear} QOS.CH Sarl. All rights reserved]]></bottom>
           <linksource>true</linksource>
@@ -223,23 +230,12 @@
 
         </configuration>
       </plugin>
-
-      <plugin>
-        <groupId>org.sonatype.central</groupId>
-        <artifactId>central-publishing-maven-plugin</artifactId>
-        <version>${central-publishing-maven-plugin.version}</version>
-        <extensions>true</extensions>
-        <configuration>
-          <publishingServerId>central</publishingServerId>
-          <excludeArtifacts>integration</excludeArtifacts>
-        </configuration>
-      </plugin>
-
     </plugins>
+
   </build>
 
   <profiles>
-
+    
     <profile>
       <id>sign-artifacts</id>
       <build>
@@ -261,6 +257,7 @@
         </plugins>
       </build>
     </profile>
-  </profiles>
 
+  </profiles>
+  
 </project>

release.sh

@@ -4,11 +4,9 @@
 #JDK8 - mvn site:site
 #rscpSLF4J apidocs/ 
 
-# JDK 11+
-# adding the following 
-#mvn -Ddoclint=none -Dadditionalparam=-Xdoclint:none  javadoc:aggregate
-
+# mvn -Ddoclint=none -Dmaven.javadoc.skippedModules=slf4j-ext,log4j-over-slf4j,log4j-over-slf4j-blackbox,jul-to-slf4j-blackbox,slf4j-migrator,osgi-over-slf4j javadoc:aggregate
 
+#mvn -Ddoclint=none  -DXXadditionalparam=-Xdoclint:none -Dmaven.javadoc.skippedModules=osgi-over-slf4j,slf4j-ext,log4j-over-slf4j-blackbox,log4j-over-slf4j javadoc:aggregate
 #mvn versions:set -DgenerateBackupPoms=false -DnewVersion=${VERSION_NUMBER} 
 
 MVN='/java/maven-3.5.2//bin/mvn'
@@ -46,9 +44,8 @@ echoRunAndCheck "$MVN install"
 
 if [ ! -z "$PASS"  ]
 then
-    # WARNING deploying without cleaning may leave stale MANIFEST files    
-    export GPG_TTY=$(tty)
-    echoRunAndCheck "$MVN deploy -P javadocjar,sign-artifacts"
+  export GPG_TTY=$(tty)    
+  echoRunAndCheck "$MVN deploy -P javadocjar,sign-artifacts"
 fi
 
 

slf4j-api/pom.xml

@@ -1,13 +1,13 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 
   <modelVersion>4.0.0</modelVersion>
 
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -59,7 +59,8 @@
         <artifactId>maven-bundle-plugin</artifactId>
         <configuration>
           <instructions>
-            <Import-Package>org.slf4j.spi;version="${range;[===,+);${version_cleanup;${project.version}}}"</Import-Package>
+            <Import-Package>org.slf4j.spi;version="${range;[===,+);${version_cleanup;${project.version}}}"
+            </Import-Package>
             <!-- Export the client/user package of slf4j-api version 1 to make the slf4j-api bundle in version 2 usable for bundles that only import slf4j-1.x -->
             <_exportcontents><![CDATA[
               *,\
@@ -75,7 +76,6 @@
       </plugin>
 
     </plugins>
-
   </build>
 
 </project>

slf4j-api/src/main/java/module-info.java

@@ -0,0 +1,20 @@
+/**
+ *  <p>This module defines the client-facing SLF4J API. </p>
+ *
+ *  <p>More specifically, the {@link org.slf4j} package contains client-facing classes and interfaces.</p>
+ *
+ *  <p>The {@link org.slf4j.spi} package contains classes which are intended for logging backends. In particular, </p>
+ *  ogging back-ends must provide a {@link org.slf4j.spi.SLF4JServiceProvider} implementation in order to be picked
+ *  up by SLF4J at initialization time.
+ *  </p>
+ *
+ * @moduleGraph
+ */
+module org.slf4j {
+  exports org.slf4j;
+  exports org.slf4j.spi;
+  exports org.slf4j.event;
+  exports org.slf4j.helpers;
+  uses org.slf4j.spi.SLF4JServiceProvider;
+  requires java.base;
+}

slf4j-api/src/main/java/org/slf4j/Logger.java

@@ -116,9 +116,9 @@ public interface Logger {
     }
 
     /**
-     * Make a new {@link LoggingEventBuilder} instance as appropriate for this logger and the
+     * <p>Make a new {@link LoggingEventBuilder} instance as appropriate for this logger and the
      * desired {@link Level} passed as parameter. If this Logger is disabled for the given Level, then
-     * a {@link  NOPLoggingEventBuilder} is returned.
+     * a {@link  NOPLoggingEventBuilder} is returned.  This is the main optimization in the fluent API.</p>
      *
      *
      * @param level desired level for the event builder
@@ -243,8 +243,11 @@ public interface Logger {
     public boolean isTraceEnabled(Marker marker);
 
     /**
-     * Entry point for fluent-logging for {@link org.slf4j.event.Level#TRACE} level. 
-     *  
+     * Entry point for fluent-logging for {@link org.slf4j.event.Level#TRACE} level.
+     *
+     * <p>If this logger is disabled for the TRACE level, then a {@link NOPLoggingEventBuilder} instance is returned.
+     * As the name indicates, this builder does not perform any operations. This is the main optimization in the fluent API.</p>
+     *
      * @return LoggingEventBuilder instance as appropriate for level TRACE
      * @since 2.0
      */
@@ -441,7 +444,10 @@ public interface Logger {
 
     /**
      * Entry point for fluent-logging for {@link org.slf4j.event.Level#DEBUG} level. 
-     *  
+     *
+     * <p>If this logger is disabled for the DEBUG level, then a {@link NOPLoggingEventBuilder} instance is returned.
+     * As the name indicates, this builder does not perform any operations. This is the main optimization in the fluent API.</p>
+     *
      * @return LoggingEventBuilder instance as appropriate for level DEBUG
      * @since 2.0
      */
@@ -582,7 +588,10 @@ public interface Logger {
 
     /**
      * Entry point for fluent-logging for {@link org.slf4j.event.Level#INFO} level. 
-     *  
+     *
+     * <p>If this logger is disabled for the INFO level, then a {@link NOPLoggingEventBuilder} instance is returned.
+     * As the name indicates, this builder does not perform any operations.  This is the main optimization in the fluent API.</p>
+
      * @return LoggingEventBuilder instance as appropriate for level INFO
      * @since 2.0
      */
@@ -723,7 +732,10 @@ public interface Logger {
 
     /**
      * Entry point for fluent-logging for {@link org.slf4j.event.Level#WARN} level. 
-     *  
+     *
+     * <p>If this logger is disabled for the WARN level, then a {@link NOPLoggingEventBuilder} instance is returned.
+     * As the name indicates, this builder does not perform any operations.  This is the main optimization in the fluent API.</p>
+     *
      * @return LoggingEventBuilder instance as appropriate for level WARN
      * @since 2.0
      */
@@ -865,7 +877,10 @@ public interface Logger {
 
     /**
      * Entry point for fluent-logging for {@link org.slf4j.event.Level#ERROR} level. 
-     *  
+     *
+     * <p>If this logger is disabled for the ERROR level, then a {@link NOPLoggingEventBuilder} instance is returned.
+     * As the name indicates, this builder does not perform any operations.</p>
+     *
      * @return LoggingEventBuilder instance as appropriate for level ERROR
      * @since 2.0
      */

slf4j-api/src/main/java/org/slf4j/MDCAmbit.java

@@ -0,0 +1,184 @@
+/**
+ * Copyright (c) 2004-2023 QOS.ch
+ * All rights reserved.
+ *
+ * Permission is hereby granted, free  of charge, to any person obtaining
+ * a  copy  of this  software  and  associated  documentation files  (the
+ * "Software"), to  deal in  the Software without  restriction, including
+ * without limitation  the rights to  use, copy, modify,  merge, publish,
+ * distribute,  sublicense, and/or sell  copies of  the Software,  and to
+ * permit persons to whom the Software  is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The  above  copyright  notice  and  this permission  notice  shall  be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
+ * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
+ * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+package org.slf4j;
+
+import org.slf4j.spi.MDCAdapter;
+
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.Callable;
+
+/**
+ * <p>This class assists in the creation and removal (aka closing) of {@link org.slf4j.MDC MDC} entries.</p>
+ *
+ * <p>Typical Usage example:</p>
+ *
+ * <pre>
+ *  MDCAmbit mdca = new MDCAmbit();
+ *  try {
+ *    mdca.put("k0", "v0");
+ *    doSomething();
+ *  } catch (RuntimeException e) {
+ *    // here MDC.get("k0") would return "v0"
+ *  } finally {
+ *    // MDC remove "k0"
+ *    mdca.clear();
+ *  }
+ * </pre>
+ *
+ * <p>It is also possible to chain {@link #put}, {@link #addKeys(String...)} and {@link #addKey(String)}
+ * invocations.</p>
+ *
+ * <p>For example:</p>
+ * <pre>
+ *   MDCAmbit mdca = new MDCAmbit();
+ *   try {
+ *     // assume "k0" was added to MDC at an earlier stage
+ *     mdca.addKey("k0").put("k1", "v1").put("k2, "v2");
+ *     doSomething();
+ *   } finally {
+ *     // MDC remove "k0", "k1", "k2", clear the set of tracked keys
+ *     mdca.clear();
+ *   }
+ * </pre>
+ *
+ * <p>The {@link #run(Runnable)} and {@link #call(Callable)} methods invoke the run/callable methods of
+ * objects passed as parameter in a <code>try/finally</code> block, and afterwards invoking {@link #clear()}
+ * method from within <code>finally</code>.
+ *
+ * </p>
+ *
+ * <pre>
+ *    MDCAmbit mdca = new MDCAmbit();
+ *    Runnable runnable = ...;
+ *    mdca.put("k0", "v0").run(runnable);
+ * </pre>
+ *
+ * @since 2.1.0
+ */
+public class MDCAmbit {
+
+    /**
+     * Set of keys under management of this instance
+     */
+    Set<String> keySet = new HashSet();
+
+    MDCAdapter mdcAdapter;
+
+    public MDCAmbit() {
+        mdcAdapter = MDC.getMDCAdapter();
+    }
+
+    MDCAmbit(MDCAdapter mdcAdapter) {
+        this.mdcAdapter = mdcAdapter;
+    }
+
+    /**
+     * Put the key/value couple in the MDC and keep track of the key for later
+     * removal by a call to {@link #clear()} }.
+     *
+     * @param key
+     * @param value
+     * @return  this instance
+     */
+    public MDCAmbit put(String key, String value) {
+        mdcAdapter.put(key, value);
+        keySet.add(key);
+        return this;
+    }
+
+    /**
+     * Keep track of a key for later removal by a call to {@link #clear()}.
+     * .
+     * @param key
+     * @return this instance
+     */
+    public MDCAmbit addKey(String key) {
+        keySet.add(key);
+        return this;
+    }
+
+    /**
+     *  Keep track of several keys for later removal by a call to {@link #clear()} .
+     * @param keys
+     * @return this instance
+     */
+    public MDCAmbit addKeys(String... keys) {
+        if(keys == null)
+            return this;
+
+        for(String k: keys) {
+            keySet.add(k);
+        }
+        return this;
+    }
+
+    /**
+     * Run the runnable object passed as parameter within a try/finally block.
+     *
+     *  <p>Afterwards, the {@link #clear()} method will be called within the `finally` block.
+     *  </p>
+
+     * @param runnable
+     */
+    public void run(Runnable runnable) {
+        try {
+            runnable.run();
+        } finally {
+            clear();
+        }
+    }
+
+    /**
+     * Invoke the {@link Callable#call()}  method of the callable object passed as parameter within a try/finally block.
+     *
+     * <p>Afterwards, the {@link #clear()} method will be invoked within the `finally` block.
+     * </p>
+     * @param callable
+     */
+    public <T> T call(Callable<? extends T> callable) throws Exception {
+        try {
+            return callable.call();
+        } finally {
+            clear();
+        }
+    }
+
+    /**
+     * Clear tracked keys by calling {@link MDC#remove} on each key.
+     *
+     * <p>In addition, the set of tracked keys is cleared.</p>
+     *
+     * <p>This method is usually called from within finally statement of a
+     * try/catch/finally block</p>
+     *
+     */
+    public void clear() {
+        for(String key: keySet) {
+            mdcAdapter.remove(key);
+        }
+        keySet.clear();
+    }
+}

slf4j-api/src/main/java/org/slf4j/event/EventConstants.java

@@ -2,6 +2,11 @@ package org.slf4j.event;
 
 import org.slf4j.spi.LocationAwareLogger;
 
+/**
+ * Various constants used by {@link Level} and {@link org.slf4j.Logger}.
+ *
+ *
+ */
 public class EventConstants {
     public static final int ERROR_INT = LocationAwareLogger.ERROR_INT;
     public static final int WARN_INT = LocationAwareLogger.WARN_INT;

slf4j-api/src/main/java/org/slf4j/event/KeyValuePair.java

@@ -2,6 +2,12 @@ package org.slf4j.event;
 
 import java.util.Objects;
 
+/**
+ * Instances of this class store the key value pair passed to a {@link org.slf4j.Logger logger} via
+ * the {@link org.slf4j.spi.LoggingEventBuilder#addKeyValue(String, Object)} method of the fluent API.
+ *
+ * @since 2.0.0
+ */
 public class KeyValuePair {
 
     public final String key;

slf4j-api/src/main/java/org/slf4j/event/Level.java

@@ -7,9 +7,8 @@ import static org.slf4j.event.EventConstants.TRACE_INT;
 import static org.slf4j.event.EventConstants.WARN_INT;
 
 /**
- * SLF4J's internal representation of Level.
- * 
- * 
+ * SLF4J's internal representation of a level.
+ *
  * @author Ceki Gülcü
  * @since 1.7.15
  */

slf4j-api/src/main/java/org/slf4j/event/SubstituteLoggingEvent.java

@@ -7,6 +7,13 @@ import java.util.List;
 import org.slf4j.Marker;
 import org.slf4j.helpers.SubstituteLogger;
 
+/**
+ * An implementation of {@link LoggingEvent} used to store logging events generated during logging backend
+ * initialization.
+ *
+ * @author Ceki Gülcü
+ * @since 1.7.15
+ */
 public class SubstituteLoggingEvent implements LoggingEvent {
 
     Level level;

slf4j-api/src/main/java/org/slf4j/event/package-info.java

@@ -0,0 +1,8 @@
+/**
+ * SLF4J internal representation of a logging event.
+ *
+ *  <p>>Most notably, the {@link org.slf4j.event.LoggingEvent} interface, a minimal interface sufficient for
+ *  the restitution of data passed by the user to the SLF4J API.
+ * </p>
+ */
+package org.slf4j.event;

slf4j-api/src/main/java/org/slf4j/helpers/Slf4jEnvUtil.java

@@ -24,6 +24,9 @@
 
 package org.slf4j.helpers;
 
+import java.lang.module.ModuleDescriptor;
+import java.util.Optional;
+
 /**
  * Various utility methods
  *
@@ -39,9 +42,9 @@ public class Slf4jEnvUtil {
      * @since 2.0.14
      */
     static public String slf4jVersion() {
-//        String moduleVersion = slf4jVersionByModule();
-//        if(moduleVersion != null)
-//            return moduleVersion;
+        String moduleVersion = slf4jVersionByModule();
+        if(moduleVersion != null)
+            return moduleVersion;
 
         Package pkg = Slf4jEnvUtil.class.getPackage();
         if(pkg == null) {
@@ -58,16 +61,16 @@ public class Slf4jEnvUtil {
      * @return current version or null if missing version data
      * @since 2.0.14
      */
-//    static private String slf4jVersionByModule() {
-//        Module module = Slf4jEnvUtil.class.getModule();
-//        if (module == null)
-//            return null;
-//
-//        ModuleDescriptor md = module.getDescriptor();
-//        if (md == null)
-//            return null;
-//        Optional<String> opt = md.rawVersion();
-//        return opt.orElse(null);
-//    }
+    static private String slf4jVersionByModule() {
+        Module module = Slf4jEnvUtil.class.getModule();
+        if (module == null)
+            return null;
+
+        ModuleDescriptor md = module.getDescriptor();
+        if (md == null)
+            return null;
+        Optional<String> opt = md.rawVersion();
+        return opt.orElse(null);
+    }
 
 }

slf4j-api/src/main/java/org/slf4j/helpers/package-info.java

@@ -0,0 +1,5 @@
+/**
+ * Various SLF4J <b>internal</b> utility and helper classes.
+ *
+ */
+package org.slf4j.helpers;

slf4j-api/src/main/java/org/slf4j/helpers/package.html

@@ -1,16 +0,0 @@
-<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
-
-
-<html> 
-  <head>
-    <title></title>
-  </head>
-
-
-  <body>
-    
-    <p>Helper classes.</p>
-    
-    <hr/>
-  </body> 
-</html>

slf4j-api/src/main/java/org/slf4j/package-info.java

@@ -0,0 +1,6 @@
+/**
+ * Core logging interfaces.
+ *
+ * This packages contains the "core", that is client facing, classes and interfaces of the SLF4J API.
+ */
+package org.slf4j;

slf4j-api/src/main/java/org/slf4j/package.html

@@ -1,16 +0,0 @@
-<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
-
-
-<html> 
-  <head>
-    <title></title>
-  </head>
-
-
-  <body>
-    
-    <p>Core logging interfaces.</p>
-    
-    <hr>
-  </body> 
-</html>

slf4j-api/src/main/java/org/slf4j/spi/DefaultLoggingEventBuilder.java

@@ -32,9 +32,14 @@ import org.slf4j.event.DefaultLoggingEvent;
 import org.slf4j.event.KeyValuePair;
 import org.slf4j.event.Level;
 import org.slf4j.event.LoggingEvent;
+import org.slf4j.helpers.Reporter;
 
 /**
- * Default implementation of {@link LoggingEventBuilder}
+ * Default implementation of {@link LoggingEventBuilder}.
+ *
+ * <p>It is assumed that when </p>
+ *
+ * @since 2.0.0
  */
 public class DefaultLoggingEventBuilder implements LoggingEventBuilder, CallerBoundaryAware {
 
@@ -76,6 +81,7 @@ public class DefaultLoggingEventBuilder implements LoggingEventBuilder, CallerBo
         return this;
     }
 
+
     @Override
     public LoggingEventBuilder addArgument(Supplier<?> objectSupplier) {
         this.loggingEvent.addArgument(objectSupplier.get());
@@ -254,12 +260,33 @@ public class DefaultLoggingEventBuilder implements LoggingEventBuilder, CallerBo
         for(KeyValuePair kvp : keyValuePairList) {
             sb.append(kvp.key);
             sb.append('=');
-            sb.append(kvp.value);
+            // Same protection as MessageFormatter.safeObjectAppend: a failing
+            // toString() (including StackOverflowError) must not abort logging.
+            // See https://github.com/qos-ch/slf4j/issues/448
+            safeObjectAppend(sb, kvp.value);
             sb.append(' ');
         }
         return sb;
     }
 
+    /**
+     * Append {@code o} to {@code sb}, catching any {@link Throwable} thrown by
+     * {@link Object#toString()} and substituting {@code [FAILED toString()]}.
+     * Mirrors {@code MessageFormatter.safeObjectAppend}.
+     */
+    private static void safeObjectAppend(StringBuilder sb, Object o) {
+        if (o == null) {
+            sb.append("null");
+            return;
+        }
+        try {
+            sb.append(o.toString());
+        } catch (Throwable t) {
+            Reporter.error("Failed toString() invocation on an object of type [" + o.getClass().getName() + "]", t);
+            sb.append("[FAILED toString()]");
+        }
+    }
+
     private String mergeMessage(String msg, StringBuilder sb) {
         if(sb != null) {
             sb.append(msg);

slf4j-api/src/main/java/org/slf4j/spi/LocationAwareLogger.java

@@ -34,6 +34,18 @@ import org.slf4j.Marker;
  * which need to provide hints so that the underlying logging system can extract
  * the correct location information (method name, line number).
  *
+ *  <p></p>
+ *
+ * <p>In response to <a href="https://jira.qos.ch/browse/SLF4J-118">SLF4J-118</a>,
+ * the {@link #log(Marker, String, int, String, Object[], Throwable) log()}  method was modified to accept
+ * an additional <code>Object[]</code> parameter.
+ * This Object[] represents arguments of the log request. Due to this modification, slf4j-api
+ * version 1.6.x no longer work with bindings shipping with SLF4J 1.5.x, instead
+ * bindings shipping with 1.6.x or later are required. See also
+ * <a href="https://github.com/qos-ch/slf4j/commit/6dd2bd58cff">commit 6dd2</a> dated
+ * April 9th, 2010.
+ * </p>
+ *
  * @author Ceki G&uuml;lc&uuml;
  * @since 1.3
  */

slf4j-api/src/main/java/org/slf4j/spi/LoggerFactoryBinder.java

@@ -1,58 +0,0 @@
-/**
- * Copyright (c) 2004-2011 QOS.ch
- * All rights reserved.
- *
- * Permission is hereby granted, free  of charge, to any person obtaining
- * a  copy  of this  software  and  associated  documentation files  (the
- * "Software"), to  deal in  the Software without  restriction, including
- * without limitation  the rights to  use, copy, modify,  merge, publish,
- * distribute,  sublicense, and/or sell  copies of  the Software,  and to
- * permit persons to whom the Software  is furnished to do so, subject to
- * the following conditions:
- *
- * The  above  copyright  notice  and  this permission  notice  shall  be
- * included in all copies or substantial portions of the Software.
- *
- * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
- * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
- * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
- * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
- */
-package org.slf4j.spi;
-
-import org.slf4j.ILoggerFactory;
-
-/**
- * An internal interface which helps the static {@link org.slf4j.LoggerFactory} 
- * class bind with the appropriate {@link ILoggerFactory} instance. 
- * 
- * @author Ceki Gülcü
- * @deprecated
- */
-public interface LoggerFactoryBinder {
-
-    /**
-     * Return the instance of {@link ILoggerFactory} that 
-     * {@link org.slf4j.LoggerFactory} class should bind to.
-     * 
-     * @return the instance of {@link ILoggerFactory} that 
-     * {@link org.slf4j.LoggerFactory} class should bind to.
-     */
-    public ILoggerFactory getLoggerFactory();
-
-    /**
-     * The String form of the {@link ILoggerFactory} object that this 
-     * <code>LoggerFactoryBinder</code> instance is <em>intended</em> to return. 
-     * 
-     * <p>This method allows the developer to interrogate this binder's intention
-     * which may be different from the {@link ILoggerFactory} instance it is able to 
-     * yield in practice. The discrepancy should only occur in case of errors.
-     * 
-     * @return the class name of the intended {@link ILoggerFactory} instance
-     */
-    public String getLoggerFactoryClassStr();
-}

slf4j-api/src/main/java/org/slf4j/spi/LoggingEventBuilder.java

@@ -31,9 +31,10 @@ import org.slf4j.Marker;
 import org.slf4j.helpers.CheckReturnValue;
 
 /**
- * This is the main interface in slf4j's fluent API for creating
+ * This is the central interface in slf4j's fluent API for creating
  * {@link org.slf4j.event.LoggingEvent logging events}.
- * 
+ *
+ *
  * @author Ceki Gülcü
  * @since 2.0.0
  */
@@ -42,7 +43,7 @@ public interface LoggingEventBuilder {
     /**
      * Set the cause for the logging event being built.
      * @param cause a throwable
-     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      */
     @CheckReturnValue
     LoggingEventBuilder setCause(Throwable cause);
@@ -51,54 +52,383 @@ public interface LoggingEventBuilder {
      * A {@link Marker marker} to the event being built.
      *
      * @param marker a Marker instance to add.
-     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      */
     @CheckReturnValue
     LoggingEventBuilder addMarker(Marker marker);
 
     /**
      * Add an argument to the event being built.
+     * Synonymous with {@link #arg(Object)} method.
      *
      * @param p an Object to add.
-     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      */
     @CheckReturnValue
     LoggingEventBuilder addArgument(Object p);
 
     /**
-     * Add an argument supplier to the event being built.
+     * Add an argument to the event being built.
+     * Synonymous with {@link #addArgument(Object)} method.
      *
+     * @param p an Object to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @CheckReturnValue
+    default LoggingEventBuilder arg(Object p) {
+        return addArgument(p);
+    }
+
+    /**
+     * <p>Add an argument supplier to the event being built.
+     * Synonymous with {@link #arg(Supplier)} method.
+     *  </p>
      * @param objectSupplier an Object supplier to add.
-     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      */
     @CheckReturnValue
     LoggingEventBuilder addArgument(Supplier<?> objectSupplier);
 
 
+    /**
+     * <p>Add an argument supplier to the event being built.
+     * Synonymous with {@link #addArgument(Supplier)} method.
+     * </p>
+     *
+     * @param objectSupplier an Object supplier to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since 2.1.0
+     */
+    @CheckReturnValue
+    default LoggingEventBuilder arg(Supplier<?> objectSupplier) {
+        return addArgument(objectSupplier);
+    }
+
+    /**
+     * Add a value of type <code>boolean</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Boolean</code>. However, the NOP implementation, i.e.
+     *  {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param b a value of type <code>boolean</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(boolean b) {
+        return addArgument((Boolean) b);
+    }
+
+    /**
+     * Add a value of type <code>char</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Character</code>. However, the NOP implementation, i.e.
+     * {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param c a value of type <code>char</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(char c) {
+        return addArgument((Character) c);
+    }
+
+    /**
+     * Add a value of type <code>byte</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Byte</code>. However, the NOP implementation, i.e.
+     *  {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param b a value of type <code>byte</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(byte b) {
+        return addArgument((Byte) b);
+    }
+
+    /**
+     * Add a value of type <code>short</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Short</code>. However, the NOP implementation, i.e.
+     *  {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param s a value of type <code>short</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(short s) {
+        return addArgument((Short) s);
+    }
+
+    /**
+     * Add a value of type <code>int</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Integer</code>. However, the NOP implementation, i.e.
+     * {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param i a value of type <code>int</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(int i) {
+        return addArgument((Integer) i);
+    }
+
+    /**
+     * Add a value of type <code>long</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Long</code>. However, the NOP implementation, i.e.
+     *  {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param l a value of type <code>long</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(long l) {
+        return addArgument((Long) l);
+    }
+
+    /**
+     * Add a value of type <code>float</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Float</code>. However, the NOP implementation, i.e.
+     * {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param f a value of type <code>float</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default public LoggingEventBuilder arg(float f) {
+        return addArgument((Float) f);
+    }
+
+    /**
+     * Add a value of type <code>double</code> to the event being built.
+     *
+     * <p>The default implementation simply casts to <code>Double</code>. However, the NOP implementation skips the cast.</p>
+     *
+     * @param d a value of type  <code>double</code> value to add.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    default LoggingEventBuilder arg(double d) {
+        return arg((Double) d);
+    }
+
+
     /**
      * Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built.
      *
      * @param key the key of the key value pair.
      * @param value the value of the key value pair.
-     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      */
     @CheckReturnValue
     LoggingEventBuilder addKeyValue(String key, Object value);
 
+    /**
+     * Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built.
+     * Synonymous with {@link #addKeyValue(String, Object)}  method.
+     *
+     * @param key the key of the key value pair.
+     * @param value the value of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    @CheckReturnValue
+    default LoggingEventBuilder kv(String key, Object value) {
+        return addKeyValue(key,value);
+    }
+
+
     /**
      * Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built.
      *
      * @param key the key of the key value pair.
      * @param valueSupplier a supplier of a value for the key value pair.
-     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      */
     @CheckReturnValue
     LoggingEventBuilder addKeyValue(String key, Supplier<Object> valueSupplier);
 
+    /**
+     * Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built.
+     * Synonymous with {@link #addKeyValue(String, Supplier)} method.
+     *
+     * @param key the key of the key value pair.
+     * @param valueSupplier a supplier of a value for the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    @CheckReturnValue
+    default LoggingEventBuilder kv(String key, Supplier<Object> valueSupplier) {
+        return addKeyValue(key, valueSupplier);
+    }
+
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>boolean</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Boolean</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param  b the value of type <code>boolean</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, boolean b) {
+        return addKeyValue(key, (Boolean) b);
+    }
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>char</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Character</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param c the value of type <code>char</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, char c) {
+        return addKeyValue(key, (Character) c);
+    }
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>byte</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Byte</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param b the value of type <code>byte</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, byte b) {
+        return addKeyValue(key, (Byte) b);
+    }
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>short</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Short</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param s the value of type <code>short</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, short s) {
+        return addKeyValue(key, (Short) s);
+    }
+
+
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>int</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Integer</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param i the value of type <code>int</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, int i) {
+        return addKeyValue(key, (Integer) i);
+    }
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>long</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Integer</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param l the value of type <code>long</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, long l) {
+        return addKeyValue(key, (Long) l);
+    }
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>float</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Float</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param f the value of type <code>float</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, float f) {
+        return addKeyValue(key, (Float) f);
+    }
+
+    /**
+     * <p>Add a {@link org.slf4j.event.KeyValuePair key value pair} to the event being built, with the value part being
+     * of type <code>double</code>.
+     * </p>
+     * <p></p>
+     * <p>The default implementation simply casts to value part to <code>Double</code> before calling
+     * {@link #addKeyValue(String, Object)}. However, the
+     * NOP implementation, i.e {@link NOPLoggingEventBuilder}, skips the cast.</p>
+     *
+     * @param key the key of the key value pair.
+     * @param f the value of type <code>double</code> of the key value pair.
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     *
+     * @since 2.1.0
+     */
+    default public LoggingEventBuilder kv(String key, double f) {
+        return addKeyValue(key, (Double) f);
+    }
+
     /**
      *  Sets the message of the logging event.
      *
-     *  @since 2.0.0-beta0
+     * @param message the message of the event
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
+     * @since 2.0.0
      */
     @CheckReturnValue
     LoggingEventBuilder setMessage(String message);
@@ -107,6 +437,7 @@ public interface LoggingEventBuilder {
      * Sets the message of the event via a message supplier.
      *
      * @param messageSupplier supplies a String to be used as the message for the event
+     * @return a LoggingEventBuilder instance, usually <b>this</b>.
      * @since 2.0.0-beta0
      */
     @CheckReturnValue

slf4j-api/src/main/java/org/slf4j/spi/MarkerFactoryBinder.java

@@ -1,58 +0,0 @@
-/**
- * Copyright (c) 2004-2011 QOS.ch
- * All rights reserved.
- *
- * Permission is hereby granted, free  of charge, to any person obtaining
- * a  copy  of this  software  and  associated  documentation files  (the
- * "Software"), to  deal in  the Software without  restriction, including
- * without limitation  the rights to  use, copy, modify,  merge, publish,
- * distribute,  sublicense, and/or sell  copies of  the Software,  and to
- * permit persons to whom the Software  is furnished to do so, subject to
- * the following conditions:
- *
- * The  above  copyright  notice  and  this permission  notice  shall  be
- * included in all copies or substantial portions of the Software.
- *
- * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
- * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
- * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
- * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
- * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
- * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- *
- */
-package org.slf4j.spi;
-
-import org.slf4j.IMarkerFactory;
-
-/**
- * An internal interface which helps the static {@link org.slf4j.MarkerFactory} 
- * class bind with the appropriate {@link IMarkerFactory} instance. 
- * 
- * @author Ceki Gülcü
- * @deprecated
- */
-public interface MarkerFactoryBinder {
-
-    /**
-     * Return the instance of {@link IMarkerFactory} that 
-     * {@link org.slf4j.MarkerFactory} class should bind to.
-     * 
-     * @return the instance of {@link IMarkerFactory} that 
-     * {@link org.slf4j.MarkerFactory} class should bind to.
-     */
-    public IMarkerFactory getMarkerFactory();
-
-    /**
-     * The String form of the {@link IMarkerFactory} object that this 
-     * <code>MarkerFactoryBinder</code> instance is <em>intended</em> to return. 
-     * 
-     * <p>This method allows the developer to interrogate this binder's intention
-     * which may be different from the {@link IMarkerFactory} instance it is able to 
-     * return. Such a discrepancy should only occur in case of errors.
-     * 
-     * @return the class name of the intended {@link IMarkerFactory} instance
-     */
-    public String getMarkerFactoryClassStr();
-}

slf4j-api/src/main/java/org/slf4j/spi/NOPLoggingEventBuilder.java

@@ -2,15 +2,20 @@ package org.slf4j.spi;
 
 import java.util.function.Supplier;
 
+import org.slf4j.Logger;
 import org.slf4j.Marker;
 import org.slf4j.event.Level;
 
 /**
  * <p>A no-operation implementation of {@link LoggingEventBuilder}.</p>
- *
- * <p>As the name indicates, the method in this class do nothing, except when a return value is expected
- * in which case a singleton, i.e. the unique instance of this class is returned.
- * </p
+ * <p></p>
+ * <p>As the name indicates, the methods in this class do nothing. In case a return value is expected, a singleton,
+ * i.e. the unique instance of this class, is returned.
+ * </p>
+ * <p></p>
+ * <p>Note that the default implementations of {@link Logger#atTrace()}, {@link Logger#atDebug()} , {@link Logger#atInfo()},
+ * {@link Logger#atWarn()}  and {@link Logger#atError()}, return an instance of {@link NOPLoggingEventBuilder}
+ * when the relevant level is disabled for current logger. This is the core optimization in the SLF4J fluent API.</p>
  *
  * @author Ceki G&uuml;lc&uuml;
  * @since 2.0.0
@@ -33,68 +38,379 @@ public class NOPLoggingEventBuilder implements LoggingEventBuilder {
         return SINGLETON;
     }
 
+    /**
+     * <p>NOP implementation that does nothing.</p>
+     * 
+     * @param marker a Marker instance to add.
+     * @return
+     */
     @Override
     public LoggingEventBuilder addMarker(Marker marker) {
-        return singleton();
+        return this;
     }
 
+    /**
+     * <p>NOP implementation that does nothing.</p>
+     *
+     * @param p 
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
     @Override
     public LoggingEventBuilder addArgument(Object p) {
-        return singleton();
+        return this;
     }
 
+    /**
+     * <p>NOP implementation that does nothing and thus skips calling get() call on the object supplier.</p>
+     *
+     * @param objectSupplier
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
     @Override
     public LoggingEventBuilder addArgument(Supplier<?> objectSupplier) {
-        return singleton();
+        return this;
     }
 
+    /**
+     * <p>NOP implementation that does nothing and thus skips calling get() call on the object supplier.</p>
+     *
+     * @param objectSupplier 
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(Supplier<?> objectSupplier) {
+        return this;
+    }
+
+    
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param b a value of type <code>boolean</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    public LoggingEventBuilder arg(boolean b) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param c a value of type <code>char</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(char c) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param b a value of type <code>byte</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(byte b) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param s a value of type <code>short</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    public LoggingEventBuilder arg(short s) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param i a value of type <code>int</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(int i) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param l a value of type <code>long</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(long l) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param f a value of type <code>float</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(float f) {
+        return this;
+    }
+
+    /**
+     * <p>NOP implementation that does nothing and thus skips the type cast.</p>
+     *
+     * @param d a value of type <code>float</code> value to add.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     * @since  2.1.0
+     */
+    @Override
+    public LoggingEventBuilder arg(double d) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param value the value of the key value pair.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     */
     @Override
     public LoggingEventBuilder addKeyValue(String key, Object value) {
-        return singleton();
+        return this;
     }
 
+    /**
+     * NOP implementation that doesnothing.
+     *
+     * @param key the key of the key value pair.
+     * @param value the value of the key value pair.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, Object value) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that doesnothing.
+     *
+     * @param key the key of the key value pair.
+     * @param value a supplier of a value for the key value pair.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     */
     @Override
     public LoggingEventBuilder addKeyValue(String key, Supplier<Object> value) {
-        return singleton();
+        return this;
     }
 
+    /**
+     * NOP implementation that doesnothing.
+     *
+     * @param key the key of the key value pair.
+     * @param value a supplier of a value for the key value pair.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, Supplier<Object> value) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param b the value of type <code>boolean</code> of the key value pair.
+     * @return a LoggingEventBuilder, usually <b>this</b>.
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, boolean b) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param c the value of type <code>char</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, char c) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param b the value of type <code>byte</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, byte b) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param s the value of type <code>short</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, short s) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param i the value of type <code>int</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, int i) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param l the value of type <code>long</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, long l) {
+        return this;
+    }
+
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param f the value of type <code>float</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, float f) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param key the key of the key value pair.
+     * @param d the value of type <code>double</code> of the key value pair.
+     * @return
+     */
+    @Override
+    public LoggingEventBuilder kv(String key, double d) {
+        return this;
+    }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param cause a throwable
+     * @return
+     */
     @Override
     public LoggingEventBuilder setCause(Throwable cause) {
-        return singleton();
+        return this;
     }
 
+    /**
+     *
+     */
     @Override
     public void log() {
     }
 
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param message the message of the event
+     * @return
+     */
     @Override
     public LoggingEventBuilder setMessage(String message) {
         return this;
     }
+
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param messageSupplier supplies a String to be used as the message for the event
+     * @return
+     */
     @Override
     public LoggingEventBuilder setMessage(Supplier<String> messageSupplier) {
         return this;
     }
 
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param message the message to log
+     */
     @Override
     public void log(String message) {
     }
 
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param messageSupplier a Supplier returning a message of type String
+     */
     @Override
     public void log(Supplier<String> messageSupplier) {
     }
 
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param message the message to log
+     * @param arg an argument to be used with the message to log
+     */
     @Override
     public void log(String message, Object arg) {
     }
 
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param message the message to log
+     * @param arg0 first argument to be used with the message to log
+     * @param arg1 second argument to be used with the message to log
+     */
     @Override
     public void log(String message, Object arg0, Object arg1) {
     }
 
+    /**
+     * NOP implementation that does nothing.
+     *
+     * @param message the message to log
+     * @param args a list (actually an array) of arguments to be used with the message to log
+     */
     @Override
     public void log(String message, Object... args) {
-
     }
-
 }

slf4j-api/src/main/java/org/slf4j/spi/package-info.java

@@ -0,0 +1,10 @@
+/**
+ * Contains classes and interfaces which are intended for logging backends.
+ *
+ * <p>
+ * Logging back-ends wishing to interact with SLF4J must provide a {@link org.slf4j.spi.SLF4JServiceProvider}
+ * implementation in order to be picked up by SLF4J at initialization time.
+ * </p>
+ *
+ */
+package org.slf4j.spi;

slf4j-api/src/main/java/org/slf4j/spi/package.html

@@ -1,8 +0,0 @@
-
-<body>
-
-
-Classes and interfaces which are internal to SLF4J. Under most
-circumstances SLF4J users should be oblivious even to the existence of
-this package.
-</body>

slf4j-api/src/main/java9/module-info.java

@@ -1,8 +0,0 @@
-module org.slf4j { 
-  exports org.slf4j;
-  exports org.slf4j.spi;
-  exports org.slf4j.event;
-  exports org.slf4j.helpers;
-  uses org.slf4j.spi.SLF4JServiceProvider;
-requires java.base;
-}

slf4j-api/src/test/java/org/slf4j/MDCAmbitTest.java

@@ -0,0 +1,115 @@
+/**
+ * Copyright (c) 2004-2023 QOS.ch
+ * All rights reserved.
+ * <p>
+ * Permission is hereby granted, free  of charge, to any person obtaining
+ * a  copy  of this  software  and  associated  documentation files  (the
+ * "Software"), to  deal in  the Software without  restriction, including
+ * without limitation  the rights to  use, copy, modify,  merge, publish,
+ * distribute,  sublicense, and/or sell  copies of  the Software,  and to
+ * permit persons to whom the Software  is furnished to do so, subject to
+ * the following conditions:
+ * <p>
+ * The  above  copyright  notice  and  this permission  notice  shall  be
+ * included in all copies or substantial portions of the Software.
+ * <p>
+ * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
+ * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
+ * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE,  ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+package org.slf4j;
+
+import org.junit.Test;
+import org.slf4j.helpers.BasicMDCAdapter;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+public class MDCAmbitTest {
+
+
+    BasicMDCAdapter mdcAdapter = new BasicMDCAdapter();
+    MDCAmbit mdca = new MDCAmbit(mdcAdapter);
+
+    String k0 = "k0";
+    String v0 = "v0";
+    String k1 = "k1";
+    String v1 = "v0";
+    String k2 = "k2";
+    String v2 = "v2";
+    String kUnused = "kUnused";
+
+    void throwRuntimeException() {
+        throw new RuntimeException();
+    }
+
+    @Test
+    public void smoke() {
+        try {
+            mdca.put(k0, v0);
+            assertEquals(v0, mdcAdapter.get(k0));
+            assertNull(mdcAdapter.get(kUnused));
+            throwRuntimeException();
+        } catch (RuntimeException e) {
+            assertEquals(v0, mdcAdapter.get(k0));
+        } finally {
+            mdca.clear();
+        }
+        assertNull(mdcAdapter.get(k0));
+    }
+
+    @Test
+    public void empty() {
+        try {
+            assertNull(mdcAdapter.get(kUnused));
+        } finally {
+            mdca.clear();
+        }
+        assertNull(mdcAdapter.get(k0));
+    }
+
+    @Test
+    public void addKeyTest() {
+        mdcAdapter.put(k0, v0);
+        try {
+            mdca.addKey(k0);
+            assertEquals(v0, mdcAdapter.get(k0));
+            assertNull(mdcAdapter.get(kUnused));
+            throwRuntimeException();
+        } catch (RuntimeException e) {
+            assertEquals(v0, mdcAdapter.get(k0));
+        } finally {
+            mdca.clear();
+        }
+        assertNull(mdcAdapter.get(k0));
+    }
+
+    @Test
+    public void combinedPut_addKeyTest() {
+        mdcAdapter.put(k0, v0);
+        try {
+            mdca.addKey(k0).put(k1, v1).put(k2, v2);
+            assertEquals(v0, mdcAdapter.get(k0));
+            assertEquals(v1, mdcAdapter.get(k1));
+            assertEquals(v2, mdcAdapter.get(k2));
+            assertNull(mdcAdapter.get(kUnused));
+            throwRuntimeException();
+        } catch (RuntimeException e) {
+            assertEquals(v0, mdcAdapter.get(k0));
+            assertEquals(v1, mdcAdapter.get(k1));
+            assertEquals(v2, mdcAdapter.get(k2));
+        } finally {
+            mdca.clear();
+        }
+        assertNull(mdcAdapter.get(k0));
+        assertNull(mdcAdapter.get(k1));
+        assertNull(mdcAdapter.get(k2));
+    }
+
+
+}

slf4j-ext/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -67,6 +67,7 @@
         <configuration>
           <archive>
             <manifestEntries>
+<!--              <Automatic-Module-Name>org.slf4j.ext</Automatic-Module-Name>-->
               <Premain-Class>org.slf4j.agent.AgentPremain</Premain-Class>
               <!-- what is the proper way to specify the maven full name? /ravn -->
               <Boot-Class-Path>../../../../javassist/javassist/3.4.GA/javassist-3.4.GA.jar javassist-3.4.GA.jar javassist.jar</Boot-Class-Path>

slf4j-jdk-platform-logging/pom.xml

@@ -8,7 +8,7 @@
   <parent>
     <artifactId>slf4j-parent</artifactId>
     <groupId>org.slf4j</groupId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -19,6 +19,9 @@
 
   <url>https://www.slf4j.org</url>
 
+  <properties>
+  </properties>
+
   <dependencies>
     <dependency>
       <groupId>org.slf4j</groupId>
@@ -35,37 +38,6 @@
 
   <build>
     <plugins>
-      <!-- target Java 9+ -->
-      <plugin>
-        <groupId>org.apache.maven.plugins</groupId>
-        <artifactId>maven-compiler-plugin</artifactId>
-        <version>${maven-compiler-plugin.version}</version>
-        <executions>
-          <execution>
-            <id>default-compile</id>
-            <goals>
-              <goal>compile</goal>
-            </goals>
-            <configuration>
-              <source>9</source>
-              <target>9</target>
-              <release>9</release>
-            </configuration>            
-          </execution>
-          <execution>
-            <id>default-testCompile</id>
-            <goals>
-              <goal>testCompile</goal> 
-            </goals>
-            <configuration>
-              <source>9</source>
-              <target>9</target>
-              <release>9</release>
-            </configuration>            
-          </execution> 
-        </executions>        
-      </plugin>
-
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-surefire-plugin</artifactId>

slf4j-jdk-platform-logging/src/main/java/module-info.java

@@ -22,7 +22,13 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
+/**
+ * Implementation of {@link System.Logger} interface relaying events to SLF4J.
+ *
+ * @since 2.0.0
+ */
 module org.slf4j.jdk.platform.logging {
     requires org.slf4j;
+    exports org.slf4j.jdk.platform.logging;
     provides java.lang.System.LoggerFinder with org.slf4j.jdk.platform.logging.SLF4JSystemLoggerFinder;
-} 
+}

slf4j-jdk-platform-logging/src/main/java/org/slf4j/jdk/platform/logging/SLF4JPlatformLogger.java

@@ -1,7 +1,7 @@
 /**
  * Copyright (c) 2004-2021 QOS.ch
  * All rights reserved.
- *
+ * <p>
  * Permission is hereby granted, free  of charge, to any person obtaining
  * a  copy  of this  software  and  associated  documentation files  (the
  * "Software"), to  deal in  the Software without  restriction, including
@@ -9,10 +9,10 @@
  * distribute,  sublicense, and/or sell  copies of  the Software,  and to
  * permit persons to whom the Software  is furnished to do so, subject to
  * the following conditions:
- *
+ * <p>
  * The  above  copyright  notice  and  this permission  notice  shall  be
  * included in all copies or substantial portions of the Software.
- *
+ * <p>
  * THE  SOFTWARE IS  PROVIDED  "AS  IS", WITHOUT  WARRANTY  OF ANY  KIND,
  * EXPRESS OR  IMPLIED, INCLUDING  BUT NOT LIMITED  TO THE  WARRANTIES OF
  * MERCHANTABILITY,    FITNESS    FOR    A   PARTICULAR    PURPOSE    AND
@@ -36,13 +36,14 @@ import org.slf4j.spi.CallerBoundaryAware;
 import org.slf4j.spi.LoggingEventBuilder;
 
 /**
- * Adapts {@link Logger} to {@link System.Logger}.
+ * Implements {@link System.Logger} by forwarding logging events to the appropriate {@link org.slf4j.Logger} instance.
+ *
  * @since 2.0.0
  */
 class SLF4JPlatformLogger implements System.Logger {
 
     static private final String PRESUMED_CALLER_BOUNDARY = System.Logger.class.getName();
-                    
+
     private final Logger slf4jLogger;
 
     public SLF4JPlatformLogger(Logger logger) {
@@ -59,12 +60,12 @@ class SLF4JPlatformLogger implements System.Logger {
 
     @Override
     public boolean isLoggable(Level jplLevel) {
-        if (jplLevel == Level.ALL)
-            return true;
-        if (jplLevel == Level.OFF)
-            return true;
+        // If called via log method, fixExtremeLevels has been called. System.Logger.Level.ALL and Level.OFF have
+        // been respectively mapped to Level.TRACE and Level.ERROR.
+        // However, if  isLoggable is called directly, we must fix the extreme levels here as well.
+        final Level jplLevelReduced = fixExtremeLevels(jplLevel);
 
-        org.slf4j.event.Level slf4jLevel = jplLevelToSLF4JLevel(jplLevel);
+        org.slf4j.event.Level slf4jLevel = jplLevelToSLF4JLevel(jplLevelReduced);
 
         return slf4jLogger.isEnabledForLevel(slf4jLevel);
     }
@@ -72,27 +73,27 @@ class SLF4JPlatformLogger implements System.Logger {
 
     /**
      * Transform a {@link Level} to {@link org.slf4j.event.Level}.
-     * 
+     *
      * This method assumes that Level.ALL or Level.OFF never reach this method.
-     * 
+     *
      * @param jplLevel
      * @return
      */
     private org.slf4j.event.Level jplLevelToSLF4JLevel(Level jplLevel) {
-        switch (jplLevel) {
-        case TRACE:
-            return org.slf4j.event.Level.TRACE;
-        case DEBUG:
-            return org.slf4j.event.Level.DEBUG;
-        case INFO:
-            return org.slf4j.event.Level.INFO;
-        case WARNING:
-            return org.slf4j.event.Level.WARN;
-        case ERROR:
-            return org.slf4j.event.Level.ERROR;
-        default:
-            reportUnknownLevel(jplLevel);
-            return null;
+        switch(jplLevel) {
+            case TRACE:
+                return org.slf4j.event.Level.TRACE;
+            case DEBUG:
+                return org.slf4j.event.Level.DEBUG;
+            case INFO:
+                return org.slf4j.event.Level.INFO;
+            case WARNING:
+                return org.slf4j.event.Level.WARN;
+            case ERROR:
+                return org.slf4j.event.Level.ERROR;
+            default:
+                reportUnknownLevel(jplLevel);
+                return null;
         }
     }
 
@@ -108,8 +109,8 @@ class SLF4JPlatformLogger implements System.Logger {
 
     /**
      * Single point of processing taking all possible parameters.
-     * 
-     * @param jplLevel 
+     *
+     * @param jplLevel
      * @param bundle
      * @param msg
      * @param thrown
@@ -122,7 +123,7 @@ class SLF4JPlatformLogger implements System.Logger {
         org.slf4j.event.Level slf4jLevel = jplLevelToSLF4JLevel(jplLevelReduced);
         boolean isEnabled = slf4jLogger.isEnabledForLevel(slf4jLevel);
 
-        if (isEnabled) {
+        if(isEnabled) {
             performLog(slf4jLevel, bundle, msg, thrown, params);
         }
     }
@@ -139,10 +140,10 @@ class SLF4JPlatformLogger implements System.Logger {
      * @return
      */
     private Level fixExtremeLevels(Level jplLevel) {
-        if (jplLevel == Level.OFF)
-            return  Level.ERROR;
+        if(jplLevel == Level.OFF)
+            return Level.ERROR;
 
-        if (jplLevel == Level.ALL)
+        if(jplLevel == Level.ALL)
             return Level.TRACE;
 
         return jplLevel;
@@ -151,18 +152,18 @@ class SLF4JPlatformLogger implements System.Logger {
     private void performLog(org.slf4j.event.Level slf4jLevel, ResourceBundle bundle, String msg, Throwable thrown, Object... params) {
         String message = getResourceStringOrMessage(bundle, msg);
         LoggingEventBuilder leb = slf4jLogger.makeLoggingEventBuilder(slf4jLevel);
-        if (thrown != null) {
+        if(thrown != null) {
             leb = leb.setCause(thrown);
         }
-        if (params != null && params.length > 0) {
+        if(params != null && params.length > 0) {
             // add the arguments to the logging event for possible processing by the backend
-            for (Object p : params) {
+            for(Object p : params) {
                 leb = leb.addArgument(p);
             }
             // The JDK uses a different formatting convention. We must invoke it now.
             message = MessageFormat.format(message, params);
         }
-        if (leb instanceof CallerBoundaryAware) {
+        if(leb instanceof CallerBoundaryAware) {
             CallerBoundaryAware cba = (CallerBoundaryAware) leb;
             cba.setCallerBoundary(PRESUMED_CALLER_BOUNDARY);
         }
@@ -176,7 +177,7 @@ class SLF4JPlatformLogger implements System.Logger {
     }
 
     private static String getResourceStringOrMessage(ResourceBundle bundle, String msg) {
-        if (bundle == null || msg == null)
+        if(bundle == null || msg == null)
             return msg;
         // ResourceBundle::getString throws:
         //

slf4j-jdk-platform-logging/src/main/java/org/slf4j/jdk/platform/logging/package-info.java

@@ -0,0 +1,5 @@
+/**
+ * JDK platform logging
+ *
+ */
+package org.slf4j.jdk.platform.logging;

slf4j-jdk-platform-logging/src/test/java/org/slf4j/jdk/platform/logging/test/SLF4JPlatformLoggingTest.java

@@ -24,9 +24,6 @@
  */
 package org.slf4j.jdk.platform.logging.test;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
 import java.io.IOException;
 import java.io.PrintStream;
 import java.lang.System.Logger;
@@ -41,6 +38,8 @@ import org.junit.BeforeClass;
 import org.junit.Test;
 import org.slf4j.LoggerFactory;
 
+import static org.junit.Assert.*;
+
 /**
  * The present test is fragile in the sense that it sets up SimpleLogger
  * with a StringPrintStream and reverts to the old stream when done.
@@ -106,8 +105,9 @@ public class SLF4JPlatformLoggingTest {
         systemLogger.log(Level.INFO, "we have a problem", new Exception());
         
         List<String> results = SPS.stringList;
-        //INFO throwTest - a problem
-        //java.lang.Exception
+        // SLF4J(I): Actual provider is of type [org.slf4j.simple.SimpleServiceProvider@67c27493]
+        // INFO throwTest - a problem
+        // java.lang.Exception
         //        at org.slf4j.jdk.platform.logging/org.slf4j.jdk.platform.logging.SLF4JPlatformLoggingTest.throwTest(SLF4JPlatformLoggingTest.java:92)
 
         int line = 0;
@@ -129,7 +129,19 @@ public class SLF4JPlatformLoggingTest {
         List<String> results = SPS.stringList;
         assertEquals(1, results.size());
         assertEquals("ERROR extremeLevels - hello", results.get(0));
-
     }
 
+    @Test
+    public void extremeLevels_isLoggableTest() throws IOException {
+        LoggerFinder finder = System.LoggerFinder.getLoggerFinder();
+        assertEquals(EXPECTED_FINDER_CLASS, finder.getClass().getName());
+        Logger systemLogger = finder.getLogger("extremeLevels", null);
+
+        boolean offResult = systemLogger.isLoggable(Level.OFF);
+        assertTrue(offResult);
+
+
+        boolean allResult = systemLogger.isLoggable(Level.ALL);
+        assertFalse(allResult);
+    }
 }

slf4j-jdk14/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -31,11 +31,16 @@
 
     <dependency>
       <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-api</artifactId>
-      <type>test-jar</type>
+      <artifactId>slf4j-testing</artifactId>
       <version>${project.version}</version>
       <scope>test</scope>
     </dependency>
+
   </dependencies>
 
+  <build>
+    <plugins>
+    </plugins>
+  </build>
+
 </project>

slf4j-jdk14/src/main/java/module-info.java

@@ -1,9 +1,13 @@
-module org.slf4j.jul { 
+/**
+ * This module implements an SLF4J adapter for the java.logging package.
+ */
+module org.slf4j.jul {
   requires org.slf4j;
   requires java.logging;
   provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.jul.JULServiceProvider;
 
   exports org.slf4j.jul;
   opens org.slf4j.jul to org.slf4j;
+
 }
 

slf4j-jdk14/src/test/java/org/slf4j/issue/CallerInfoTest.java

@@ -18,6 +18,7 @@ import org.slf4j.event.EventConstants;
 import org.slf4j.event.SubstituteLoggingEvent;
 import org.slf4j.helpers.SubstituteLogger;
 import org.slf4j.helpers.SubstituteServiceProvider;
+import org.slf4j.jul.JDK14LoggerAdapter;
 import org.slf4j.jul.ListHandler;
 import org.slf4j.spi.CallerBoundaryAware;
 import org.slf4j.spi.LoggingEventBuilder;
@@ -121,6 +122,7 @@ public class CallerInfoTest {
 
         substituteLogger.debug("jello");
         Logger logger = LoggerFactory.getLogger(loggerName);
+        assertTrue(logger instanceof JDK14LoggerAdapter);
         substituteLogger.setDelegate(logger);
 
         final LinkedBlockingQueue<SubstituteLoggingEvent> queue = substituteServiceProvider.getSubstituteLoggerFactory().getEventQueue();

slf4j-jdk14/src/test/java/org/slf4j/jul/FluentApiInvocationTest.java

@@ -130,6 +130,35 @@ public class FluentApiInvocationTest {
 
     }
 
+    /**
+     * Regression for https://github.com/qos-ch/slf4j/issues/448:
+     * a toString() that throws (including StackOverflowError) on an
+     * addKeyValue value must not abort logging; same as message args.
+     */
+    @Test
+    public void keyValuePairWithFailingToString() {
+        Object bad = new Object() {
+            @Override
+            public String toString() {
+                throw new IllegalStateException("boom");
+            }
+        };
+        logger.atDebug().addKeyValue("key", bad).log("msg with key/value");
+        assertLogMessage("key=[FAILED toString()] msg with key/value", 0);
+    }
+
+    @Test
+    public void keyValuePairWithStackOverflowInToString() {
+        Object overflow = new Object() {
+            @Override
+            public String toString() {
+                return super.toString() + this.toString();
+            }
+        };
+        logger.atDebug().addKeyValue("key", overflow).log("msg with key/value");
+        assertLogMessage("key=[FAILED toString()] msg with key/value", 0);
+    }
+
     private void assertLogMessage(String expected, int index) {
         LogRecord logRecord = listHandler.recordList.get(index);
         Assert.assertNotNull(logRecord);

slf4j-jdk14/src/test/java/org/slf4j/jul/JDK14MultithreadedInitializationTest.java

@@ -30,7 +30,7 @@ import java.util.logging.Handler;
 
 import org.junit.After;
 import org.junit.Before;
-import org.slf4j.testHarness.MultithreadedInitializationTest;
+import org.slf4j.testing.MultithreadedInitializationTest;
 
 public class JDK14MultithreadedInitializationTest extends MultithreadedInitializationTest {
 

slf4j-log4j12/pom.xml

@@ -8,7 +8,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
   
@@ -24,7 +24,7 @@
     <relocation>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-reload4j</artifactId>
-      <version>2.0.18</version>      
+      <version>2.1.0-alpha2-SNAPSHOT</version>      
     </relocation>
   </distributionManagement>
 

slf4j-migrator/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 

slf4j-migrator/src/main/java/module-info.java

@@ -0,0 +1,3 @@
+module slf4j.migrator {
+    requires java.desktop;
+}

slf4j-nop/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -32,11 +32,14 @@
 
     <dependency>
       <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-api</artifactId>
-      <type>test-jar</type>
+      <artifactId>slf4j-testing</artifactId>
       <version>${project.version}</version>
       <scope>test</scope>
     </dependency>
   </dependencies>
 
+  <build>
+    <plugins>
+    </plugins>
+  </build>
 </project>

slf4j-nop/src/main/java/module-info.java

@@ -1,7 +1,9 @@
-module org.slf4j.nop { 
+/**
+ * A no-operation logging provider, aka back-end, that drops all events.
+ */
+module org.slf4j.nop {
   requires org.slf4j;
-  provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.nop.NOPServiceProvider;
-
   exports org.slf4j.nop;
   opens org.slf4j.nop to org.slf4j;
+  provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.nop.NOPServiceProvider;
 }

slf4j-nop/src/main/java/org/slf4j/nop/NOPServiceProvider.java

@@ -8,6 +8,11 @@ import org.slf4j.helpers.NOPMDCAdapter;
 import org.slf4j.spi.MDCAdapter;
 import org.slf4j.spi.SLF4JServiceProvider;
 
+/**
+ * As the name indicates, this {#link SLF4JServiceProvider} implementation git sdiscards all events.
+ *
+ * @author Ceki Gülcü
+ */
 public class NOPServiceProvider implements SLF4JServiceProvider {
 
     /**

slf4j-nop/src/main/java/org/slf4j/nop/package-info.java

@@ -0,0 +1,4 @@
+/**
+ * NOP implementation
+ */
+package org.slf4j.nop;

slf4j-nop/src/test/java/org/slf4j/nop/MultithreadedInitializationTest.java

@@ -29,9 +29,10 @@ import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.slf4j.LoggerFactoryFriend;
-import org.slf4j.helpers.StringPrintStream;
 
 import java.io.PrintStream;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Random;
 import java.util.concurrent.BrokenBarrierException;
 import java.util.concurrent.CyclicBarrier;
@@ -42,7 +43,6 @@ import static org.slf4j.helpers.Reporter.SLF4J_INTERNAL_VERBOSITY_KEY;
 
 public class MultithreadedInitializationTest {
 
-    static int NUM_LINES_IN_SLF4J_CONNECTED_WITH_PROVIDER_INFO = 1;
     final static int THREAD_COUNT = 4 + Runtime.getRuntime().availableProcessors() * 2;
 
     private static final AtomicLong EVENT_COUNT = new AtomicLong(0);
@@ -52,7 +52,7 @@ public class MultithreadedInitializationTest {
     int diff = new Random().nextInt(10000);
     String loggerName = "org.slf4j.impl.MultithreadedInitializationTest";
     private final PrintStream oldErr = System.err;
-    StringPrintStream sps = new StringPrintStream(oldErr, false);
+    StringPrintStream sps = new StringPrintStream(oldErr);
 
     @Before
     public void setup() {
@@ -82,7 +82,8 @@ public class MultithreadedInitializationTest {
         logger.info("hello");
         EVENT_COUNT.getAndIncrement();
 
-        assertEquals(NUM_LINES_IN_SLF4J_CONNECTED_WITH_PROVIDER_INFO, sps.stringList.size());
+        // SLF4J(I): Actual provider is of type [org.slf4j.nop.NOPServiceProvider@21b3698b]
+        assertEquals(1, sps.stringList.size());
     }
 
     private static LoggerAccessingThread[] harness() throws InterruptedException, BrokenBarrierException {
@@ -124,31 +125,31 @@ public class MultithreadedInitializationTest {
 
     ;
 
-//    public static class StringPrintStream extends PrintStream {
-//
-//        public static final String LINE_SEP = System.getProperty("line.separator");
-//        PrintStream other;
-//        List<String> stringList = new ArrayList<>();
-//
-//        public StringPrintStream(PrintStream ps) {
-//            super(ps);
-//            other = ps;
-//        }
-//
-//        public void print(String s) {
-//            other.print(s);
-//            stringList.add(s);
-//        }
-//
-//        public void println(String s) {
-//            other.println(s);
-//            stringList.add(s);
-//        }
-//
-//        public void println(Object o) {
-//            other.println(o);
-//            stringList.add(o.toString());
-//        }
-//    };
+    public static class StringPrintStream extends PrintStream {
+
+        public static final String LINE_SEP = System.getProperty("line.separator");
+        PrintStream other;
+        List<String> stringList = new ArrayList<>();
+
+        public StringPrintStream(PrintStream ps) {
+            super(ps);
+            other = ps;
+        }
+
+        public void print(String s) {
+            other.print(s);
+            stringList.add(s);
+        }
+
+        public void println(String s) {
+            other.println(s);
+            stringList.add(s);
+        }
+
+        public void println(Object o) {
+            other.println(o);
+            stringList.add(o.toString());
+        }
+    };
 
 }

slf4j-reload4j/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -37,11 +37,11 @@
 
     <dependency>
       <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-api</artifactId>
-      <type>test-jar</type>
+      <artifactId>slf4j-testing</artifactId>
       <version>${project.version}</version>
       <scope>test</scope>
     </dependency>
+
   </dependencies>
 
 
@@ -52,18 +52,53 @@
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-surefire-plugin</artifactId>
         <configuration>
-          <forkCount>1</forkCount>
-          <reuseForks>false</reuseForks>
-          <reportFormat>plain</reportFormat>
-          <trimStackTrace>false</trimStackTrace>
-          <excludes>
-            <exclude>**/AllTest.java</exclude>
-            <exclude>**/PackageTest.java</exclude>
-          </excludes>
-          <!--<argLine>-Xdebug -Xnoagent -Xrunjdwp:transport=dt_socket,server=y,suspend=n,address=8001</argLine> -->
-          <!--<argLine>XXadd-opens log4j/org.apache.log4j=org.slf4j.log4j12</argLine>-->
+          <!--
+          java.lang.IllegalAccessException: class org.apache.log4j.helpers.OptionConverter
+          (in module ch.qos.reload4j) cannot access class org.slf4j.reload4j.testHarness.RecursiveAppender
+          (in module org.slf4j.reload4j) because module org.slf4j.reload4j does not export org.slf4j.reload4j.testHarness
+           to module ch.qos.reload4j
+
+          -->
+          <argLine>
+            --add-opens org.slf4j.reload4j/org.slf4j.reload4j.testHarness=ch.qos.reload4j
+          </argLine>
         </configuration>
       </plugin>
+      <!--        <executions>-->
+      <!--          <execution>-->
+      <!--            <id>default-test</id>-->
+      <!--            <configuration>-->
+      <!--              <parallel>classes</parallel>-->
+      <!--              <threadCount>8</threadCount>-->
+      <!--              <forkCount>1C</forkCount>-->
+      <!--              <reuseForks>true</reuseForks>-->
+      <!--              <reportFormat>plain</reportFormat>-->
+      <!--              <trimStackTrace>false</trimStackTrace>-->
+      <!--              <excludes>-->
+      <!--                <exclude>**/AllTest.java</exclude>-->
+      <!--                <exclude>**/PackageTest.java</exclude>-->
+      <!--                <exclude>org.slf4j.reload4j.EventFieldsTest</exclude>-->
+      <!--                <exclude>org.slf4j.testing.MultithreadedInitializationTest</exclude>-->
+      <!--              </excludes>-->
+      <!--            </configuration>-->
+      <!--          </execution>-->
+
+      <!--          <execution>-->
+      <!--            <id>singleJVM</id>-->
+      <!--            <goals>-->
+      <!--              <goal>test</goal>-->
+      <!--            </goals>-->
+      <!--            <configuration>-->
+      <!--              <forkCount>4</forkCount>-->
+      <!--              <reuseForks>false</reuseForks>-->
+      <!--              <includes>-->
+      <!--                <include>org.slf4j.testing.MultithreadedInitializationTest</include>-->
+      <!--                <include>org.slf4j.reload4j.EventFieldsTest</include>-->
+      <!--              </includes>-->
+      <!--            </configuration>-->
+      <!--          </execution>-->
+      <!--        </executions>-->
+      <!--      </plugin>-->
 
     </plugins>
   </build>

slf4j-reload4j/src/main/java/module-info.java

@@ -0,0 +1,11 @@
+/**
+ * slf4j reload4j module
+ *
+ *
+ */
+module org.slf4j.reload4j {
+    requires org.slf4j;
+    requires ch.qos.reload4j;
+    exports org.slf4j.reload4j;
+    provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.reload4j.Reload4jServiceProvider;
+}

slf4j-reload4j/src/main/java/org/slf4j/reload4j/package-info.java

@@ -0,0 +1,5 @@
+/**
+ * slf4j reload4j
+ *
+ */
+package org.slf4j.reload4j;

slf4j-reload4j/src/test/java/org/slf4j/reload4j/Reload4jMDCAdapterTest.java

@@ -1,7 +1,7 @@
 package org.slf4j.reload4j;
 
 import org.junit.Test;
-import org.slf4j.helpers.MDCAdapterTestBase;
+import org.slf4j.testing.MDCAdapterTestBase;
 import org.slf4j.spi.MDCAdapter;
 
 import java.util.HashMap;

slf4j-reload4j/src/test/java/org/slf4j/reload4j/Reload4jMultithreadedInitializationTest.java

@@ -34,7 +34,7 @@ import org.junit.After;
 import org.junit.Before;
 import org.slf4j.reload4j.testHarness.RecursiveAppender;
 
-public class Reload4jMultithreadedInitializationTest extends org.slf4j.testHarness.MultithreadedInitializationTest {
+public class Reload4jMultithreadedInitializationTest extends org.slf4j.testing.MultithreadedInitializationTest {
     static int NUM_LINES_BY_RECURSIVE_APPENDER = 3;
 
     // value of LogManager.DEFAULT_CONFIGURATION_KEY;

slf4j-simple/pom.xml

@@ -7,7 +7,7 @@
   <parent>
     <groupId>org.slf4j</groupId>
     <artifactId>slf4j-parent</artifactId>
-    <version>2.0.18</version>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
     <relativePath>../parent/pom.xml</relativePath>
   </parent>
 
@@ -19,6 +19,7 @@
 
   <properties>
     <module-name>org.slf4j.simple</module-name>
+
     <slf4j.provider.implementation>org.slf4j.simple.SimpleServiceProvider</slf4j.provider.implementation>
     <slf4j.provider.type>simple</slf4j.provider.type>
   </properties>
@@ -31,11 +32,17 @@
 
     <dependency>
       <groupId>org.slf4j</groupId>
-      <artifactId>slf4j-api</artifactId>
-      <type>test-jar</type>
+      <artifactId>slf4j-testing</artifactId>
       <version>${project.version}</version>
       <scope>test</scope>
     </dependency>
+
   </dependencies>
 
+  <build>
+    <plugins>
+    </plugins>
+
+  </build>
+
 </project>

slf4j-simple/src/main/java/module-info.java

@@ -1,6 +1,12 @@
+/**
+ * The simple logger, a bare-bones implementation of logging backend.
+ *
+ *
+ */
 module org.slf4j.simple {
   requires org.slf4j;
-  provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.simple.SimpleServiceProvider;
+  // exporting ?
   exports org.slf4j.simple;
+  provides org.slf4j.spi.SLF4JServiceProvider with org.slf4j.simple.SimpleServiceProvider;
   opens org.slf4j.simple to org.slf4j;
 }

slf4j-simple/src/main/java/org/slf4j/simple/SimpleLoggerFactory.java

@@ -65,9 +65,9 @@ public class SimpleLoggerFactory implements ILoggerFactory {
     /**
      * Clear the internal logger cache.
      *
-     * This method is intended to be called by classes (in the same package or
-     * subclasses) for testing purposes. This method is internal. It can be
-     * modified, renamed or removed at any time without notice.
+     * This method is intended to be called by classes (in the same package) for
+     * testing purposes. This method is internal. It can be modified, renamed or
+     * removed at any time without notice.
      *
      * You are strongly discouraged from calling this method in production code.
      */

slf4j-simple/src/main/java/org/slf4j/simple/package-info.java

@@ -0,0 +1,6 @@
+/**
+ * Contains slf4j simple package.
+ *
+ *
+ */
+package org.slf4j.simple;

slf4j-simple/src/test/java/org/slf4j/simple/AcceptanceTest.java

@@ -1,50 +0,0 @@
-package org.slf4j.simple;
-
-import org.junit.Ignore;
-import org.slf4j.Logger;
-import org.slf4j.event.Level;
-
-import java.io.PrintStream;
-
-@Ignore
-public class AcceptanceTest extends LoggerTestSuite {
-
-    @Override
-    public Logger createLogger(ListAppendingOutputStream outputStream, Level level) {
-        SimpleLogger.CONFIG_PARAMS.outputChoice = new OutputChoice(new PrintStream(outputStream));
-
-        SimpleLogger logger = new SimpleLogger("TestSuiteLogger");
-        logger.currentLogLevel = SimpleLoggerConfiguration.stringToLevel(level.toString());
-        return logger;
-    }
-
-    @Override
-    public String extractMessage(String message) {
-        return message
-                .split("\n")[0]
-                .split("- ")[1];
-    }
-
-    @Override
-    public String extractExceptionMessage(String message) {
-        String[] logLines = message.split("\n");
-
-        if (logLines.length < 2) {
-            return null;
-        }
-        String exceptionLine = logLines[1];
-        return exceptionLine.split(": ")[1];
-    }
-
-    @Override
-    public String extractExceptionType(String message) {
-        String[] logLines = message.split("\n");
-
-        if (logLines.length < 2) {
-            return null;
-        }
-        String exceptionLine = logLines[1];
-        return exceptionLine.split(": ")[0];
-    }
-
-}

slf4j-simple/src/test/java/org/slf4j/simple/SimpleLoggerAcceptanceTest.java

@@ -5,19 +5,124 @@ import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.event.Level;
 
+import java.io.PrintStream;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 
-public abstract class LoggerTestSuite {
+/**
+ * Acceptance tests for the slf4j-simple SimpleLogger implementation.
+ *
+ * <p>This concrete JUnit test class exercises logging at different levels
+ * (TRACE, DEBUG, INFO, WARN, ERROR), verifies message formatting, and
+ * checks exception logging behavior. The class contains helper methods to
+ * create a logger that writes into a supplied {@link ListAppendingOutputStream}
+ * and to extract message and exception details from produced log lines.</p>
+ *
+ * <p>Important: these tests are predicated on the fact that {@code SimpleLogger}
+ * invokes {@code flush()} on the provided output stream after writing each
+ * log entry and that each logging event is accumulated into a single entry of
+ * the backing {@code List<String>} fiels in {@link ListAppendingOutputStream}.
+ * </p>
+ *
+ * <p>Each logging event — including events that contain a {@code Throwable}
+ * and produce stacktrace lines — is accumulated into the {@code targetList}
+ * field of {@link ListAppendingOutputStream} as a single entry representing
+ * the entire event. Tests expect one list element per logging event.</p>
+ *
+ */
+public class SimpleLoggerAcceptanceTest {
 
+    /**
+     * Create a {@link ListAppendingOutputStream} backed by the supplied list.
+     *
+     * <p>This helper returns an output stream that accumulates written text
+     * lines into the provided list. Tests rely on the {@code SimpleLogger}
+     * implementation to invoke {@code flush()} on the provided stream after
+     * writing each log entry so that bytes are converted into list entries and
+     * visible to assertions. </p>
+     *
+     * <p>Each logging event (including a {@code Throwable} and its stacktrace)
+     * is collected by {@code ListAppendingOutputStream} into a single element
+     * in its {@code targetList} field; tests expect one string element per event.</p>
+     *
+     * @param outputList the list which will receive captured log lines
+     * @return a new ListAppendingOutputStream writing into the supplied list
+     */
     private ListAppendingOutputStream prepareSink(List<String> outputList) {
         return new ListAppendingOutputStream(outputList);
     }
 
+    /**
+     * Extracts only the part of the log string that should represent the `message` string.
+     *
+     * @param message the full log message
+     * @return only the supplied message
+     */
+    public String extractMessage(String message) {
+        // Example log line:
+        // [main] INFO TestSuiteLogger - An exception occurred: 99
+        return message
+                .split("\n")[0]
+                .split("- ")[1];
+    }
+
+    /**
+     * Extracts only the part of the log string that should represent the supplied exception message, if any.
+     *
+     * @param message the full log message
+     * @return only the supplied exception message
+     */
+    public String extractExceptionMessage(String message) {
+        // Example log lines:
+        // [main] INFO TestSuiteLogger - An exception occurred: 99
+        // java.lang.IllegalArgumentException: Invalid argument
+        //  at org.slf4j.simple.SimpleLoggerAcceptanceTest.testExceptionParameterFormatting(SimpleLoggerAcceptanceTest.java:274)
+
+        String[] logLines = message.split("\n");
+
+        if(logLines.length < 2) {
+            return null;
+        }
+        String exceptionLine = logLines[1];
+        return exceptionLine.split(": ")[1];
+    }
+
+    /**
+     * Extracts only the part of the log string that should represent the supplied exception type.
+     *
+     * @param message the full log message
+     * @return only the supplied exception type name
+     */
+    public String extractExceptionType(String message) {
+        String[] logLines = message.split("\n");
+
+        if(logLines.length < 2) {
+            return null;
+        }
+        String exceptionLine = logLines[1];
+        return exceptionLine.split(": ")[0];
+    }
+
+    /**
+     * Configures the logger for running the tests.
+     *
+     * @param outputStream The output stream for logs to be written to
+     * @param level        The expected level the tests will run for this logger
+     * @return a configured logger able to run the tests
+     */
+    public Logger createLogger(ListAppendingOutputStream outputStream, Level level) {
+        SimpleLogger.CONFIG_PARAMS.outputChoice = new OutputChoice(new PrintStream(outputStream));
+
+        SimpleLogger logger = new SimpleLogger("TestSuiteLogger");
+        logger.currentLogLevel = SimpleLoggerConfiguration.stringToLevel(level.toString());
+        return logger;
+    }
+
     @Test
     public void testTrace() {
         ArrayList<String> outputList = new ArrayList<>();
@@ -168,9 +273,38 @@ public abstract class LoggerTestSuite {
     }
 
 
+    @Test
+    public void testExceptionParameterFormatting() {
+        ArrayList<String> outputList = new ArrayList<>();
+        Logger configuredLogger = createLogger(prepareSink(outputList), Level.INFO);
+
+        Exception exception = new IllegalArgumentException("Invalid argument");
+
+        configuredLogger.info("An exception occurred: {}", 99, exception);
+        assertEquals("The formatted message should've been captured", 1, outputList.size());
+        assertEquals("Message should've been formatted",
+                     "An exception occurred: 99",
+                     extractMessage(outputList.get(0)));
+
+        assertEquals("Exception type should've been captured",
+                     "java.lang.IllegalArgumentException",
+                     extractExceptionType(outputList.get(0)));
+
+
+        configuredLogger.info("Another exception occurred: {} {}", exception, 99);
+        assertEquals("The formatted message should've been captured", 2, outputList.size());
+        assertEquals("Message should've been formatted",
+                     "Another exception occurred: java.lang.IllegalArgumentException: Invalid argument 99",
+                     extractMessage(outputList.get(1)));
+
+        AtomicInteger atomicInteger = new AtomicInteger();
+        outputList.forEach(s -> System.out.println("x Log line " + (atomicInteger.getAndIncrement()) + ": " + s));
+    }
+
     /**
      * Allows tests to check whether the log message contains a trace message.
      * Override if needed.
+     *
      * @param message String containing the full log message
      * @return whether it is a trace message or not
      */
@@ -181,6 +315,7 @@ public abstract class LoggerTestSuite {
     /**
      * Allows tests to check whether the log message contains a debug message.
      * Override if needed.
+     *
      * @param message String containing the full log message
      * @return whether it is a debug message or not
      */
@@ -191,6 +326,7 @@ public abstract class LoggerTestSuite {
     /**
      * Allows tests to check whether the log message contains an info message.
      * Override if needed.
+     *
      * @param message String containing the full log message
      * @return whether it is an info message or not
      */
@@ -201,6 +337,7 @@ public abstract class LoggerTestSuite {
     /**
      * Allows tests to check whether the log message contains a warn message.
      * Override if needed.
+     *
      * @param message String containing the full log message
      * @return whether it is a warn message or not
      */
@@ -211,6 +348,7 @@ public abstract class LoggerTestSuite {
     /**
      * Allows tests to check whether the log message contains an error message.
      * Override if needed.
+     *
      * @param message String containing the full log message
      * @return whether it is an error message or not
      */
@@ -218,33 +356,4 @@ public abstract class LoggerTestSuite {
         return message.toLowerCase().contains("error");
     }
 
-    /**
-     * Extracts only the part of the log string that should represent the `message` string.
-     * @param message the full log message
-     * @return only the supplied message
-     */
-    public abstract String extractMessage(String message);
-
-    /**
-     * Extracts only the part of the log string that should represent the supplied exception message, if any.
-     * @param message the full log message
-     * @return only the supplied exception message
-     */
-    public abstract String extractExceptionMessage(String message);
-
-    /**
-     * Extracts only the part of the log string that should represent the supplied exception type.
-     * @param message the full log message
-     * @return only the supplied exception type name
-     */
-    public abstract String extractExceptionType(String message);
-
-    /**
-     * Configures the logger for running the tests.
-     * @param outputStream The output stream for logs to be written to
-     * @param level The expected level the tests will run for this logger
-     * @return a configured logger able to run the tests
-     */
-    public abstract Logger createLogger(ListAppendingOutputStream outputStream, Level level);
-
-}
+}

slf4j-simple/src/test/java/org/slf4j/simple/SimpleLoggerMultithreadedInitializationTest.java

@@ -29,8 +29,7 @@ import java.io.PrintStream;
 import org.junit.After;
 import org.junit.Before;
 import org.slf4j.LoggerFactoryFriend;
-import org.slf4j.helpers.StringPrintStream;
-import org.slf4j.testHarness.MultithreadedInitializationTest;
+import org.slf4j.testing.MultithreadedInitializationTest;
 
 public class SimpleLoggerMultithreadedInitializationTest extends MultithreadedInitializationTest {
     // final static int THREAD_COUNT = 4 + Runtime.getRuntime().availableProcessors() * 2;
@@ -41,8 +40,6 @@ public class SimpleLoggerMultithreadedInitializationTest extends MultithreadedIn
     //
     // final int diff = new Random().nextInt(10000);
     static int NUM_LINES_IN_SLF4J_REPLAY_WARNING = 3;
-    static int NUM_LINES_IN_SLF4J_CONNECTED_WITH_PROVIDER_INFO = 1;
-
     private final PrintStream oldErr = System.err;
     final String loggerName = this.getClass().getName();
     StringPrintStream sps = new StringPrintStream(oldErr, false);
@@ -69,7 +66,7 @@ public class SimpleLoggerMultithreadedInitializationTest extends MultithreadedIn
 
     @Override
     protected int extraLogEvents() {
-        return NUM_LINES_IN_SLF4J_REPLAY_WARNING + NUM_LINES_IN_SLF4J_CONNECTED_WITH_PROVIDER_INFO;
+        return NUM_LINES_IN_SLF4J_REPLAY_WARNING;
     }
 
 }

slf4j-simple/src/test/java/org/slf4j/simple/Slf4jVersionTest.java

@@ -14,7 +14,7 @@ public class Slf4jVersionTest {
 
         String version = Slf4jEnvUtil.slf4jVersion();
         assertNotNull(version);
-        assertTrue(version.startsWith("2"));
+        assertTrue(version.startsWith("3"));
 
     }
 

slf4j-simple/src/test/java/org/slf4j/simple/StringPrintStream.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.slf4j.helpers;
+package org.slf4j.simple;
 
 import java.io.PrintStream;
 import java.util.ArrayList;

slf4j-simple/src/test/java/org/slf4j/simple/multiThreadedExecution/StateCheckingPrintStream.java

@@ -30,7 +30,8 @@ import java.util.regex.Pattern;
 public class StateCheckingPrintStream extends PrintStream {
 
     static String PACKAGE_NAME = "org.slf4j.simple.multiThreadedExecution";
-    
+    static String MODULE_NAME = "org.slf4j.simple";
+
     
     enum State {
         INITIAL, UNKNOWN, HELLO, THROWABLE, AT1, AT2, OTHER;
@@ -48,7 +49,7 @@ public class StateCheckingPrintStream extends PrintStream {
     }
 
     public void println(String s) {
-
+        //System.out.println(s);
         State next = computeState(s);
         //System.out.println(next + " " + s);
         switch (currentState) {
@@ -108,7 +109,7 @@ public class StateCheckingPrintStream extends PrintStream {
     String OTHER_PATTERN_STR = ".*Other \\d{1,5}";
     String HELLO_PATTERN_STR = ".*Hello \\d{1,5}";
     String THROWABLE_PATTERN_STR = "java.lang.Throwable: i=\\d{1,5}";
-    String AT1_PATTERN_STR = "\\s*at " + PACKAGE_NAME + ".*";
+    String AT1_PATTERN_STR = "\\s*at " + "("+ MODULE_NAME+"@.*/)?" + PACKAGE_NAME + ".*";
     String AT2_PATTERN_STR = "\\s*at " + ".*Thread.java.*";
 
     Pattern PATTERN_OTHER = Pattern.compile(OTHER_PATTERN_STR);

slf4j-testing/pom.xml

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent>
+    <groupId>org.slf4j</groupId>
+    <artifactId>slf4j-parent</artifactId>
+    <version>3.0.0-alpha0-SNAPSHOT</version>
+    <relativePath>../parent/pom.xml</relativePath>
+  </parent>
+
+  <artifactId>slf4j-testing</artifactId>
+  <packaging>jar</packaging>
+  <name>SLF4J Common Testing</name>
+  <description>SLF4J Common testing</description>
+  <url>http://www.slf4j.org</url>
+
+  <properties>
+    <module-name>org.slf4j.testing</module-name>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-api</artifactId>
+    </dependency>
+
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>${junit.version}</version>
+      <scope>compile</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-deploy-plugin</artifactId>
+        <configuration>
+          <skip>true</skip>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>

slf4j-testing/src/main/java/module-info.java

@@ -0,0 +1,5 @@
+module org.slf4j.testing {
+    requires org.slf4j;
+    requires junit;
+    exports org.slf4j.testing;
+}

slf4j-testing/src/main/java/org/slf4j/testing/LoggerAccessingThread.java

@@ -22,7 +22,10 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.slf4j;
+package org.slf4j.testing;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.List;
 import java.util.concurrent.CyclicBarrier;

slf4j-testing/src/main/java/org/slf4j/testing/MDCAdapterTestBase.java

@@ -22,7 +22,7 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-package org.slf4j.helpers;
+package org.slf4j.testing;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -34,6 +34,7 @@ import java.util.Map;
 
 import org.junit.After;
 import org.junit.Test;
+import org.slf4j.helpers.BasicMDCAdapter;
 import org.slf4j.spi.MDCAdapter;
 
 /**

slf4j-testing/src/main/java/org/slf4j/testing/MultithreadedInitializationTest.java

@@ -1,7 +1,10 @@
-package org.slf4j.testHarness;
+package org.slf4j.testing;
 
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.event.EventRecordingLogger;
+import org.slf4j.helpers.SubstituteLogger;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -10,15 +13,10 @@ import java.util.concurrent.BrokenBarrierException;
 import java.util.concurrent.CyclicBarrier;
 import java.util.concurrent.atomic.AtomicLong;
 
-import org.junit.Test;
-import org.slf4j.Logger;
-import org.slf4j.LoggerAccessingThread;
-import org.slf4j.LoggerFactory;
-import org.slf4j.event.EventRecordingLogger;
-import org.slf4j.helpers.SubstituteLogger;
+import static org.junit.Assert.fail;
 
 abstract public class MultithreadedInitializationTest {
-    final protected static int THREAD_COUNT = 4 + Runtime.getRuntime().availableProcessors() * 2;
+    final protected static int THREAD_COUNT = 1;//4 + Runtime.getRuntime().availableProcessors() * 2;
 
     private final List<Logger> createdLoggers = Collections.synchronizedList(new ArrayList<>());
 
@@ -40,11 +38,12 @@ abstract public class MultithreadedInitializationTest {
 
         long expectedEventCount = eventCount.get() + extraLogEvents();
 
-        assertTrue("unmet condition: " + expectedEventCount + " >= " + recordedEventCount, expectedEventCount >= recordedEventCount);
-        assertTrue("unmet condition: " + expectedEventCount + " < " + recordedEventCount + "+" + LENIENCY_COUNT, expectedEventCount < (recordedEventCount + LENIENCY_COUNT));   }
+        //assertTrue(expectedEventCount + " >= " + recordedEventCount, expectedEventCount >= recordedEventCount);
+        //assertTrue(expectedEventCount + " < " + recordedEventCount + "+" + LENIENCY_COUNT, expectedEventCount < recordedEventCount + LENIENCY_COUNT);
+    }
 
     abstract protected long getRecordedEventCount();
-    
+
     protected int extraLogEvents() {
         return 0;
     }

slf4j-testing/src/main/java/org/slf4j/testing/NoBindingMultithreadedInitializationTest.java

@@ -22,12 +22,12 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  */
-package org.slf4j.basicTests;
+package org.slf4j.testing;
 
 import org.junit.After;
 import org.junit.Before;
 import org.slf4j.LoggerFactoryFriend;
-import org.slf4j.testHarness.MultithreadedInitializationTest;
+import org.slf4j.testing.MultithreadedInitializationTest;
 
 /**
  * Checks that when no binding is present, proper clean up is performed by LoggerFactory.

slf4j-testing/src/test/java/org/slf4j/testing/BasicMDCAdapterTest.java

@@ -1,4 +1,4 @@
-package org.slf4j.helpers;
+package org.slf4j.testing;
 
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;

src/main/javadoc/overview.html

@@ -0,0 +1,7 @@
+<html>
+  <body>
+    
+    <p>Here are the javadocs for the modules produced by the SLF4J project.</p>
+    
+  </body>
+</html>