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1   /*
2    * Copyright 2010 Red Hat, Inc.
3    *
4    * Red Hat licenses this file to you under the Apache License, version 2.0
5    * (the "License"); you may not use this file except in compliance with the
6    * License.  You may obtain a copy of the License at:
7    *
8    *    http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
13   * License for the specific language governing permissions and limitations
14   * under the License.
15   */
16  package org.jboss.netty.example.objectecho;
17  
18  import java.util.ArrayList;
19  import java.util.List;
20  import java.util.concurrent.atomic.AtomicLong;
21  import java.util.logging.Level;
22  import java.util.logging.Logger;
23  
24  import org.jboss.netty.channel.ChannelEvent;
25  import org.jboss.netty.channel.ChannelHandlerContext;
26  import org.jboss.netty.channel.ChannelState;
27  import org.jboss.netty.channel.ChannelStateEvent;
28  import org.jboss.netty.channel.ExceptionEvent;
29  import org.jboss.netty.channel.MessageEvent;
30  import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
31  
32  /**
33   * Handler implementation for the object echo client.  It initiates the
34   * ping-pong traffic between the object echo client and server by sending the
35   * first message to the server.
36   *
37   * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
38   * @author <a href="http://gleamynode.net/">Trustin Lee</a>
39   *
40   * @version $Rev: 2121 $, $Date: 2010-02-02 09:38:07 +0900 (Tue, 02 Feb 2010) $
41   */
42  public class ObjectEchoClientHandler extends SimpleChannelUpstreamHandler {
43  
44      private static final Logger logger = Logger.getLogger(
45              ObjectEchoClientHandler.class.getName());
46  
47      private final List<Integer> firstMessage;
48      private final AtomicLong transferredMessages = new AtomicLong();
49  
50      /**
51       * Creates a client-side handler.
52       */
53      public ObjectEchoClientHandler(int firstMessageSize) {
54          if (firstMessageSize <= 0) {
55              throw new IllegalArgumentException(
56                      "firstMessageSize: " + firstMessageSize);
57          }
58          firstMessage = new ArrayList<Integer>(firstMessageSize);
59          for (int i = 0; i < firstMessageSize; i ++) {
60              firstMessage.add(Integer.valueOf(i));
61          }
62      }
63  
64      public long getTransferredMessages() {
65          return transferredMessages.get();
66      }
67  
68      @Override
69      public void handleUpstream(
70              ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
71          if (e instanceof ChannelStateEvent &&
72              ((ChannelStateEvent) e).getState() != ChannelState.INTEREST_OPS) {
73              logger.info(e.toString());
74          }
75          super.handleUpstream(ctx, e);
76      }
77  
78      @Override
79      public void channelConnected(
80              ChannelHandlerContext ctx, ChannelStateEvent e) {
81          // Send the first message if this handler is a client-side handler.
82          e.getChannel().write(firstMessage);
83      }
84  
85      @Override
86      public void messageReceived(
87              ChannelHandlerContext ctx, MessageEvent e) {
88          // Echo back the received object to the client.
89          transferredMessages.incrementAndGet();
90          e.getChannel().write(e.getMessage());
91      }
92  
93      @Override
94      public void exceptionCaught(
95              ChannelHandlerContext ctx, ExceptionEvent e) {
96          logger.log(
97                  Level.WARNING,
98                  "Unexpected exception from downstream.",
99                  e.getCause());
100         e.getChannel().close();
101     }
102 }