Store datagram channel's remoteAddress as much as possible within the extent that does not cause a race condition

src/main/java/org/jboss/netty/channel/socket/nio/NioDatagramChannel.java

@@ -22,7 +22,8 @@
  */
 package org.jboss.netty.channel.socket.nio;
 
-import static org.jboss.netty.channel.Channels.*;
+import static org.jboss.netty.channel.Channels.fireChannelInterestChanged;
+import static org.jboss.netty.channel.Channels.fireChannelOpen;
 
 import java.io.IOException;
 import java.net.InetAddress;
@@ -121,6 +122,7 @@ class NioDatagramChannel extends AbstractChannel
     volatile boolean inWriteNowLoop;
 
     private volatile InetSocketAddress localAddress;
+    volatile InetSocketAddress remoteAddress;
 
     NioDatagramChannel(final ChannelFactory factory,
             final ChannelPipeline pipeline, final ChannelSink sink,
@@ -158,12 +160,17 @@ class NioDatagramChannel extends AbstractChannel
     }
 
     public InetSocketAddress getRemoteAddress() {
-        try {
+        InetSocketAddress remoteAddress = this.remoteAddress;
-            return (InetSocketAddress) datagramChannel.socket().getRemoteSocketAddress();
+        if (remoteAddress == null) {
-        } catch (Throwable t) {
+            try {
-            // Sometimes fails on a closed socket in Windows.
+                this.remoteAddress = remoteAddress =
-            return null;
+                    (InetSocketAddress) datagramChannel.socket().getRemoteSocketAddress();
+            } catch (Throwable t) {
+                // Sometimes fails on a closed socket in Windows.
+                return null;
+            }
         }
+        return remoteAddress;
     }
 
     public boolean isBound() {

src/main/java/org/jboss/netty/channel/socket/nio/NioDatagramPipelineSink.java

@@ -22,7 +22,11 @@
  */
 package org.jboss.netty.channel.socket.nio;
 
-import static org.jboss.netty.channel.Channels.*;
+import static org.jboss.netty.channel.Channels.fireChannelBound;
+import static org.jboss.netty.channel.Channels.fireChannelClosed;
+import static org.jboss.netty.channel.Channels.fireChannelConnected;
+import static org.jboss.netty.channel.Channels.fireChannelUnbound;
+import static org.jboss.netty.channel.Channels.fireExceptionCaught;
 
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
@@ -174,6 +178,10 @@ class NioDatagramPipelineSink extends AbstractChannelSink {
 
         future.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
 
+        // Clear the cached address so that the next getRemoteAddress() call
+        // updates the cache.
+        channel.remoteAddress = null;
+
         try {
             channel.getDatagramChannel().connect(remoteAddress);
             connected = true;

src/main/java/org/jboss/netty/channel/socket/oio/OioDatagramChannel.java

@@ -22,7 +22,7 @@
  */
 package org.jboss.netty.channel.socket.oio;
 
-import static org.jboss.netty.channel.Channels.*;
+import static org.jboss.netty.channel.Channels.fireChannelOpen;
 
 import java.io.IOException;
 import java.net.InetAddress;
@@ -58,6 +58,7 @@ final class OioDatagramChannel extends AbstractChannel
     private final DatagramChannelConfig config;
     volatile Thread workerThread;
     private volatile InetSocketAddress localAddress;
+    volatile InetSocketAddress remoteAddress;
 
     OioDatagramChannel(
             ChannelFactory factory,
@@ -102,12 +103,17 @@ final class OioDatagramChannel extends AbstractChannel
     }
 
     public InetSocketAddress getRemoteAddress() {
-        try {
+        InetSocketAddress remoteAddress = this.remoteAddress;
-            return (InetSocketAddress) socket.getRemoteSocketAddress();
+        if (remoteAddress == null) {
-        } catch (Throwable t) {
+            try {
-            // Sometimes fails on a closed socket in Windows.
+                this.remoteAddress = remoteAddress =
-            return null;
+                    (InetSocketAddress) socket.getRemoteSocketAddress();
+            } catch (Throwable t) {
+                // Sometimes fails on a closed socket in Windows.
+                return null;
+            }
         }
+        return remoteAddress;
     }
 
     public boolean isBound() {

src/main/java/org/jboss/netty/channel/socket/oio/OioDatagramPipelineSink.java

@@ -22,7 +22,9 @@
  */
 package org.jboss.netty.channel.socket.oio;
 
-import static org.jboss.netty.channel.Channels.*;
+import static org.jboss.netty.channel.Channels.fireChannelBound;
+import static org.jboss.netty.channel.Channels.fireChannelConnected;
+import static org.jboss.netty.channel.Channels.fireExceptionCaught;
 
 import java.net.SocketAddress;
 import java.util.concurrent.Executor;
@@ -135,6 +137,10 @@ class OioDatagramPipelineSink extends AbstractChannelSink {
 
         future.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
 
+        // Clear the cached address so that the next getRemoteAddress() call
+        // updates the cache.
+        channel.remoteAddress = null;
+
         try {
             channel.socket.connect(remoteAddress);
             connected = true;