Merge pull request #46 from ceefour/findbugs

Add `@Nonnull` annotation to aid findbugs / Eclipse IDE.

Pretty innocuous; JSR305 annotations are definitely the norm in many circles.

slf4j-api/pom.xml

@@ -19,7 +19,12 @@
   <url>http://www.slf4j.org</url>
 
   <dependencies>
-
+  	<dependency>
+  		<groupId>com.google.code.findbugs</groupId>
+  		<artifactId>jsr305</artifactId>
+  		<version>2.0.1</version>
+  		<optional>true</optional>
+  	</dependency>
   </dependencies> 
 
   <build>

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

@@ -24,6 +24,8 @@
  */
 package org.slf4j;
 
+import javax.annotation.Nonnull;
+
 
 /**
  * <code>ILoggerFactory</code> instances manufacture {@link Logger}
@@ -54,5 +56,6 @@ public interface ILoggerFactory {
    * @param name the name of the Logger to return
    * @return a Logger instance 
    */
-  public Logger getLogger(String name);
+  @Nonnull
+  public Logger getLogger(@Nonnull String name);
 }

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

@@ -26,7 +26,14 @@ package org.slf4j;
 
 import java.io.IOException;
 import java.net.URL;
-import java.util.*;
+import java.util.Arrays;
+import java.util.Enumeration;
+import java.util.Iterator;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+
+import javax.annotation.Nonnull;
 
 import org.slf4j.helpers.NOPLoggerFactory;
 import org.slf4j.helpers.SubstituteLogger;
@@ -272,7 +279,8 @@ public final class LoggerFactory {
    * @param name The name of the logger.
    * @return logger
    */
-  public static Logger getLogger(String name) {
+  @Nonnull
+  public static Logger getLogger(@Nonnull String name) {
     ILoggerFactory iLoggerFactory = getILoggerFactory();
     return iLoggerFactory.getLogger(name);
   }
@@ -284,7 +292,8 @@ public final class LoggerFactory {
    * @param clazz the returned logger will be named after clazz
    * @return logger
    */
-  public static Logger getLogger(Class clazz) {
+  @Nonnull
+  public static Logger getLogger(@Nonnull Class clazz) {
     return getLogger(clazz.getName());
   }
 
@@ -296,6 +305,7 @@ public final class LoggerFactory {
    *
    * @return the ILoggerFactory instance in use
    */
+  @Nonnull
   public static ILoggerFactory getILoggerFactory() {
     if (INITIALIZATION_STATE == UNINITIALIZED) {
       INITIALIZATION_STATE = ONGOING_INITIALIZATION;