Fixed issue: NETTY-310 Memory leak in netty-3.2.0.BETA1.jar

* Added a special internal use only constructor to AbstractChannel, which bypasses ID allocation
* EmbeddedChannel calls the special purpose constructor to avoid leak

src/main/java/org/jboss/netty/channel/AbstractChannel.java

@@ -59,7 +59,7 @@ public abstract class AbstractChannel implements Channel {
         }
     }
 
-    private final Integer id = allocateId(this);
+    private final Integer id;
     private final Channel parent;
     private final ChannelFactory factory;
     private final ChannelPipeline pipeline;
@@ -90,7 +90,36 @@ public abstract class AbstractChannel implements Channel {
         this.parent = parent;
         this.factory = factory;
         this.pipeline = pipeline;
+
+        id = allocateId(this);
         closeFuture.addListener(ID_DEALLOCATOR);
+
+        pipeline.attach(this, sink);
+    }
+
+    /**
+     * (Internal use only) Creates a new temporary instance with the specified
+     * ID.
+     *
+     * @param parent
+     *        the parent of this channel. {@code null} if there's no parent.
+     * @param factory
+     *        the factory which created this channel
+     * @param pipeline
+     *        the pipeline which is going to be attached to this channel
+     * @param sink
+     *        the sink which will receive downstream events from the pipeline
+     *        and send upstream events to the pipeline
+     */
+    protected AbstractChannel(
+            Integer id,
+            Channel parent, ChannelFactory factory,
+            ChannelPipeline pipeline, ChannelSink sink) {
+
+        this.id = id;
+        this.parent = parent;
+        this.factory = factory;
+        this.pipeline = pipeline;
         pipeline.attach(this, sink);
     }
 

src/main/java/org/jboss/netty/handler/codec/embedder/EmbeddedChannel.java

@@ -24,18 +24,23 @@ import org.jboss.netty.channel.ChannelSink;
 import org.jboss.netty.channel.DefaultChannelConfig;
 
 /**
+ * TODO Make EmbeddedChannel implement ChannelConfig and ChannelSink to reduce overhead.
+ * TODO Do not extend AbstractChannel to reduce overhead and remove the internal-use-only constructor in AbstractChannel.
+ *
  * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
  * @author <a href="http://gleamynode.net/">Trustin Lee</a>
  * @version $Rev$, $Date$
  */
 class EmbeddedChannel extends AbstractChannel {
 
+    private static final Integer DUMMY_ID = Integer.valueOf(0);
+
     private final ChannelConfig config;
     private final SocketAddress localAddress = new EmbeddedSocketAddress();
     private final SocketAddress remoteAddress = new EmbeddedSocketAddress();
 
     EmbeddedChannel(ChannelPipeline pipeline, ChannelSink sink) {
-        super(null, EmbeddedChannelFactory.INSTANCE, pipeline, sink);
+        super(DUMMY_ID, null, EmbeddedChannelFactory.INSTANCE, pipeline, sink);
         config = new DefaultChannelConfig();
     }