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1   /*
2    * Copyright 2009 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.handler.traffic;
17  
18  
19  import org.jboss.netty.channel.ChannelHandlerContext;
20  import org.jboss.netty.channel.ChannelPipelineFactory;
21  import org.jboss.netty.channel.ChannelStateEvent;
22  import org.jboss.netty.handler.execution.ExecutionHandler;
23  import org.jboss.netty.handler.execution.MemoryAwareThreadPoolExecutor;
24  import org.jboss.netty.handler.execution.OrderedMemoryAwareThreadPoolExecutor;
25  import org.jboss.netty.util.ObjectSizeEstimator;
26  import org.jboss.netty.util.Timer;
27  
28  /**
29   * This implementation of the {@link AbstractTrafficShapingHandler} is for channel
30   * traffic shaping, that is to say a per channel limitation of the bandwidth.<br><br>
31   *
32   * The general use should be as follow:<br>
33   * <ul>
34   * <li>Add in your pipeline a new ChannelTrafficShapingHandler, before a recommended {@link ExecutionHandler} (like
35   * {@link OrderedMemoryAwareThreadPoolExecutor} or {@link MemoryAwareThreadPoolExecutor}).<br>
36   * <tt>ChannelTrafficShapingHandler myHandler = new ChannelTrafficShapingHandler(timer);</tt><br>
37   * timer could be created using <tt>HashedWheelTimer<tt><br>
38   * <tt>pipeline.addLast("CHANNEL_TRAFFIC_SHAPING", myHandler);</tt><br><br>
39   *
40   * <b>Note that this handler has a Pipeline Coverage of "one" which means a new handler must be created
41   * for each new channel as the counter cannot be shared among all channels.</b> For instance, if you have a
42   * {@link ChannelPipelineFactory}, you should create a new ChannelTrafficShapingHandler in this
43   * {@link ChannelPipelineFactory} each time getPipeline() method is called.<br><br>
44   *
45   * Other arguments can be passed like write or read limitation (in bytes/s where 0 means no limitation)
46   * or the check interval (in millisecond) that represents the delay between two computations of the
47   * bandwidth and so the call back of the doAccounting method (0 means no accounting at all).<br><br>
48   *
49   * A value of 0 means no accounting for checkInterval. If you need traffic shaping but no such accounting,
50   * it is recommended to set a positive value, even if it is high since the precision of the
51   * Traffic Shaping depends on the period where the traffic is computed. The highest the interval,
52   * the less precise the traffic shaping will be. It is suggested as higher value something close
53   * to 5 or 10 minutes.<br>
54   * </li>
55   * <li>When you shutdown your application, release all the external resources (except the timer internal itself)
56   * by calling:<br>
57   * <tt>myHandler.releaseExternalResources();</tt><br>
58   * </li>
59   * </ul><br>
60   *
61   * @author The Netty Project (netty-dev@lists.jboss.org)
62   * @author Frederic Bregier
63   */
64  public class ChannelTrafficShapingHandler extends AbstractTrafficShapingHandler {
65  
66      /**
67       * @param timer
68       * @param writeLimit
69       * @param readLimit
70       * @param checkInterval
71       */
72      public ChannelTrafficShapingHandler(Timer timer, long writeLimit,
73              long readLimit, long checkInterval) {
74          super(timer, writeLimit, readLimit, checkInterval);
75      }
76  
77      /**
78       * @param timer
79       * @param writeLimit
80       * @param readLimit
81       */
82      public ChannelTrafficShapingHandler(Timer timer, long writeLimit,
83              long readLimit) {
84          super(timer, writeLimit, readLimit);
85      }
86  
87      /**
88       * @param timer
89       * @param checkInterval
90       */
91      public ChannelTrafficShapingHandler(Timer timer, long checkInterval) {
92          super(timer, checkInterval);
93      }
94  
95      /**
96       * @param timer
97       */
98      public ChannelTrafficShapingHandler(Timer timer) {
99          super(timer);
100     }
101 
102     /**
103      * @param objectSizeEstimator
104      * @param timer
105      * @param writeLimit
106      * @param readLimit
107      * @param checkInterval
108      */
109     public ChannelTrafficShapingHandler(
110             ObjectSizeEstimator objectSizeEstimator, Timer timer,
111             long writeLimit, long readLimit, long checkInterval) {
112         super(objectSizeEstimator, timer, writeLimit, readLimit,
113                 checkInterval);
114     }
115 
116     /**
117      * @param objectSizeEstimator
118      * @param timer
119      * @param writeLimit
120      * @param readLimit
121      */
122     public ChannelTrafficShapingHandler(
123             ObjectSizeEstimator objectSizeEstimator, Timer timer,
124             long writeLimit, long readLimit) {
125         super(objectSizeEstimator, timer, writeLimit, readLimit);
126     }
127 
128     /**
129      * @param objectSizeEstimator
130      * @param timer
131      * @param checkInterval
132      */
133     public ChannelTrafficShapingHandler(
134             ObjectSizeEstimator objectSizeEstimator, Timer timer,
135             long checkInterval) {
136         super(objectSizeEstimator, timer, checkInterval);
137     }
138 
139     /**
140      * @param objectSizeEstimator
141      * @param timer
142      */
143     public ChannelTrafficShapingHandler(
144             ObjectSizeEstimator objectSizeEstimator, Timer timer) {
145         super(objectSizeEstimator, timer);
146     }
147 
148     @Override
149     public void channelClosed(ChannelHandlerContext ctx, ChannelStateEvent e)
150             throws Exception {
151         if (trafficCounter != null) {
152             trafficCounter.stop();
153         }
154         super.channelClosed(ctx, e);
155     }
156 
157     @Override
158     public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e)
159             throws Exception {
160         // readSuspended = true;
161         ctx.setAttachment(Boolean.TRUE);
162         ctx.getChannel().setReadable(false);
163         if (trafficCounter == null) {
164             // create a new counter now
165             if (timer != null) {
166                 trafficCounter = new TrafficCounter(this, timer, "ChannelTC" +
167                         ctx.getChannel().getId(), checkInterval);
168             }
169         }
170         if (trafficCounter != null) {
171             trafficCounter.start();
172         }
173         super.channelConnected(ctx, e);
174         // readSuspended = false;
175         ctx.setAttachment(null);
176         ctx.getChannel().setReadable(true);
177     }
178 
179 }