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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.localtime;
17  
18  import java.util.ArrayList;
19  import java.util.Collection;
20  import java.util.Formatter;
21  import java.util.List;
22  import java.util.concurrent.BlockingQueue;
23  import java.util.concurrent.LinkedBlockingQueue;
24  import java.util.logging.Level;
25  import java.util.logging.Logger;
26  
27  import org.jboss.netty.channel.Channel;
28  import org.jboss.netty.channel.ChannelEvent;
29  import org.jboss.netty.channel.ChannelHandlerContext;
30  import org.jboss.netty.channel.ChannelStateEvent;
31  import org.jboss.netty.channel.ExceptionEvent;
32  import org.jboss.netty.channel.MessageEvent;
33  import org.jboss.netty.channel.SimpleChannelUpstreamHandler;
34  import org.jboss.netty.example.localtime.LocalTimeProtocol.Continent;
35  import org.jboss.netty.example.localtime.LocalTimeProtocol.LocalTime;
36  import org.jboss.netty.example.localtime.LocalTimeProtocol.LocalTimes;
37  import org.jboss.netty.example.localtime.LocalTimeProtocol.Location;
38  import org.jboss.netty.example.localtime.LocalTimeProtocol.Locations;
39  
40  public class LocalTimeClientHandler extends SimpleChannelUpstreamHandler {
41  
42      private static final Logger logger = Logger.getLogger(
43              LocalTimeClientHandler.class.getName());
44  
45      // Stateful properties
46      private volatile Channel channel;
47      private final BlockingQueue<LocalTimes> answer = new LinkedBlockingQueue<LocalTimes>();
48  
49      public List<String> getLocalTimes(Collection<String> cities) {
50          Locations.Builder builder = Locations.newBuilder();
51  
52          for (String c: cities) {
53              String[] components = c.split("/");
54              builder.addLocation(Location.newBuilder().
55                  setContinent(Continent.valueOf(components[0].toUpperCase())).
56                  setCity(components[1]).build());
57          }
58  
59          channel.write(builder.build());
60  
61          LocalTimes localTimes;
62          boolean interrupted = false;
63          for (;;) {
64              try {
65                  localTimes = answer.take();
66                  break;
67              } catch (InterruptedException e) {
68                  interrupted = true;
69              }
70          }
71  
72          if (interrupted) {
73              Thread.currentThread().interrupt();
74          }
75  
76          List<String> result = new ArrayList<String>();
77          for (LocalTime lt: localTimes.getLocalTimeList()) {
78              result.add(
79                      new Formatter().format(
80                              "%4d-%02d-%02d %02d:%02d:%02d %s",
81                              lt.getYear(),
82                              lt.getMonth(),
83                              lt.getDayOfMonth(),
84                              lt.getHour(),
85                              lt.getMinute(),
86                              lt.getSecond(),
87                              lt.getDayOfWeek().name()).toString());
88          }
89  
90          return result;
91      }
92  
93      @Override
94      public void handleUpstream(
95              ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
96          if (e instanceof ChannelStateEvent) {
97              logger.info(e.toString());
98          }
99          super.handleUpstream(ctx, e);
100     }
101 
102     @Override
103     public void channelOpen(ChannelHandlerContext ctx, ChannelStateEvent e)
104             throws Exception {
105         channel = e.getChannel();
106         super.channelOpen(ctx, e);
107     }
108 
109     @Override
110     public void messageReceived(
111             ChannelHandlerContext ctx, final MessageEvent e) {
112         boolean offered = answer.offer((LocalTimes) e.getMessage());
113         assert offered;
114     }
115 
116     @Override
117     public void exceptionCaught(
118             ChannelHandlerContext ctx, ExceptionEvent e) {
119         logger.log(
120                 Level.WARNING,
121                 "Unexpected exception from downstream.",
122                 e.getCause());
123         e.getChannel().close();
124     }
125 }