Fix a NPE in DefaultChannelPipeline.write(...)

- Also re-enabled logging handler in the echo example

example/src/main/java/io/netty/example/echo/EchoClient.java

@@ -22,6 +22,8 @@ import io.netty.channel.ChannelOption;
 import io.netty.channel.socket.SocketChannel;
 import io.netty.channel.socket.nio.NioEventLoop;
 import io.netty.channel.socket.nio.NioSocketChannel;
+import io.netty.handler.logging.LogLevel;
+import io.netty.handler.logging.LoggingHandler;
 
 import java.net.InetSocketAddress;
 
@@ -55,7 +57,7 @@ public class EchoClient {
                  @Override
                  public void initChannel(SocketChannel ch) throws Exception {
                      ch.pipeline().addLast(
-                             //new LoggingHandler(LogLevel.INFO),
+                             new LoggingHandler(LogLevel.INFO),
                              new EchoClientHandler(firstMessageSize));
                  }
              });

example/src/main/java/io/netty/example/echo/EchoServer.java

@@ -19,10 +19,11 @@ import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.ChannelOption;
-import io.netty.channel.socket.ServerSocketChannel;
 import io.netty.channel.socket.SocketChannel;
 import io.netty.channel.socket.nio.NioEventLoop;
 import io.netty.channel.socket.nio.NioServerSocketChannel;
+import io.netty.handler.logging.LogLevel;
+import io.netty.handler.logging.LoggingHandler;
 
 import java.net.InetSocketAddress;
 
@@ -46,17 +47,12 @@ public class EchoServer {
              .option(ChannelOption.SO_BACKLOG, 100)
              .localAddress(new InetSocketAddress(port))
              .childOption(ChannelOption.TCP_NODELAY, true)
-             .handler(new ChannelInitializer<ServerSocketChannel>() {
-                @Override
-                public void initChannel(ServerSocketChannel ch) throws Exception {
-                    //ch.pipeline().addLast(new LoggingHandler(LogLevel.INFO));
-                }
-             })
+             .handler(new LoggingHandler(LogLevel.INFO))
              .childHandler(new ChannelInitializer<SocketChannel>() {
                  @Override
                  public void initChannel(SocketChannel ch) throws Exception {
                      ch.pipeline().addLast(
-                             //new LoggingHandler(LogLevel.INFO),
+                             new LoggingHandler(LogLevel.INFO),
                              new EchoServerHandler());
                  }
              });

transport/src/main/java/io/netty/channel/DefaultChannelPipeline.java

@@ -1471,7 +1471,7 @@ public class DefaultChannelPipeline implements ChannelPipeline {
                 msgBuf = true;
                 executor = ctx.executor();
                 break;
-            } else if (message instanceof ChannelBuffer) {
+            } if (message instanceof ChannelBuffer && ctx.hasOutboundByteBuffer()) {
                 executor = ctx.executor();
                 break;
             }