View Javadoc

1   /*
2    * Copyright 2012 The Netty Project
3    *
4    * The Netty Project licenses this file to you under the Apache License,
5    * version 2.0 (the "License"); you may not use this file except in compliance
6    * with the 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.telnet;
17  
18  import java.util.logging.Level;
19  import java.util.logging.Logger;
20  
21  import org.jboss.netty.channel.ChannelEvent;
22  import org.jboss.netty.channel.ChannelHandlerContext;
23  import org.jboss.netty.channel.ChannelStateEvent;
24  import org.jboss.netty.channel.ExceptionEvent;
25  import org.jboss.netty.channel.MessageEvent;
26  import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
27  
28  /**
29   * Handles a client-side channel.
30   */
31  public class TelnetClientHandler extends SimpleChannelUpstreamHandler {
32  
33      private static final Logger logger = Logger.getLogger(
34              TelnetClientHandler.class.getName());
35  
36      @Override
37      public void handleUpstream(
38              ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
39          if (e instanceof ChannelStateEvent) {
40              logger.info(e.toString());
41          }
42          super.handleUpstream(ctx, e);
43      }
44  
45      @Override
46      public void messageReceived(
47              ChannelHandlerContext ctx, MessageEvent e) {
48          // Print out the line received from the server.
49          System.err.println(e.getMessage());
50      }
51  
52      @Override
53      public void exceptionCaught(
54              ChannelHandlerContext ctx, ExceptionEvent e) {
55          logger.log(
56                  Level.WARNING,
57                  "Unexpected exception from downstream.",
58                  e.getCause());
59          e.getChannel().close();
60      }
61  }