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Java > Open Source Codes > org > apache > mina > handler > StreamIoHandler


1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one
3  * or more contributor license agreements. See the NOTICE file
4  * distributed with this work for additional information
5  * regarding copyright ownership. The ASF licenses this file
6  * to you under the Apache License, Version 2.0 (the
7  * "License"); you may not use this file except in compliance
8  * with the License. You may obtain a copy of the License at
9  *
10  * http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing,
13  * software distributed under the License is distributed on an
14  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15  * KIND, either express or implied. See the License for the
16  * specific language governing permissions and limitations
17  * under the License.
18  *
19  */
20 package org.apache.mina.handler;
21
22 import java.io.IOException JavaDoc;
23 import java.io.InputStream JavaDoc;
24 import java.io.OutputStream JavaDoc;
25 import java.net.SocketTimeoutException JavaDoc;
26
27 import org.apache.mina.common.ByteBuffer;
28 import org.apache.mina.common.IdleStatus;
29 import org.apache.mina.common.IoHandler;
30 import org.apache.mina.common.IoHandlerAdapter;
31 import org.apache.mina.common.IoSession;
32 import org.apache.mina.handler.support.IoSessionInputStream;
33 import org.apache.mina.handler.support.IoSessionOutputStream;
34 import org.apache.mina.util.SessionLog;
35
36 /**
37  * A {@link IoHandler} that adapts asynchronous MINA events to stream I/O.
38  * <p>
39  * Please extend this class and implement
40  * {@link #processStreamIo(IoSession, InputStream, OutputStream)} to
41  * execute your stream I/O logic; <b>please note that you must forward
42  * the process request to other thread or thread pool.</b>
43  *
44  * @author The Apache Directory Project (mina-dev@directory.apache.org)
45  * @version $Rev: 555855 $, $Date: 2007-07-13 12:19:00 +0900 (금, 13 7월 2007) $
46  */
47 public abstract class StreamIoHandler extends IoHandlerAdapter {
48     private static final String JavaDoc KEY_IN = StreamIoHandler.class.getName()
49             + ".in";
50
51     private static final String JavaDoc KEY_OUT = StreamIoHandler.class.getName()
52             + ".out";
53
54     private int readTimeout;
55
56     private int writeTimeout;
57
58     protected StreamIoHandler() {
59     }
60
61     /**
62      * Implement this method to execute your stream I/O logic;
63      * <b>please note that you must forward the process request to other
64      * thread or thread pool.</b>
65      */
66     protected abstract void processStreamIo(IoSession session, InputStream JavaDoc in,
67             OutputStream JavaDoc out);
68
69     /**
70      * Returns read timeout in seconds.
71      * The default value is <tt>0</tt> (disabled).
72      */
73     public int getReadTimeout() {
74         return readTimeout;
75     }
76
77     /**
78      * Sets read timeout in seconds.
79      * The default value is <tt>0</tt> (disabled).
80      */
81     public void setReadTimeout(int readTimeout) {
82         this.readTimeout = readTimeout;
83     }
84
85     /**
86      * Returns write timeout in seconds.
87      * The default value is <tt>0</tt> (disabled).
88      */
89     public int getWriteTimeout() {
90         return writeTimeout;
91     }
92
93     /**
94      * Sets write timeout in seconds.
95      * The default value is <tt>0</tt> (disabled).
96      */
97     public void setWriteTimeout(int writeTimeout) {
98         this.writeTimeout = writeTimeout;
99     }
100
101     /**
102      * Initializes streams and timeout settings.
103      */
104     public void sessionOpened(IoSession session) {
105         // Set timeouts
106 session.setWriteTimeout(writeTimeout);
107         session.setIdleTime(IdleStatus.READER_IDLE, readTimeout);
108
109         // Create streams
110 InputStream JavaDoc in = new IoSessionInputStream();
111         OutputStream JavaDoc out = new IoSessionOutputStream(session);
112         session.setAttribute(KEY_IN, in);
113         session.setAttribute(KEY_OUT, out);
114         processStreamIo(session, in, out);
115     }
116
117     /**
118      * Closes streams
119      */
120     public void sessionClosed(IoSession session) throws Exception JavaDoc {
121         final InputStream JavaDoc in = (InputStream JavaDoc) session.getAttribute(KEY_IN);
122         final OutputStream JavaDoc out = (OutputStream JavaDoc) session.getAttribute(KEY_OUT);
123         try {
124             in.close();
125         } finally {
126             out.close();
127         }
128     }
129
130     /**
131      * Forwards read data to input stream.
132      */
133     public void messageReceived(IoSession session, Object JavaDoc buf) {
134         final IoSessionInputStream in = (IoSessionInputStream) session
135                 .getAttribute(KEY_IN);
136         in.write((ByteBuffer) buf);
137     }
138
139     /**
140      * Forwards caught exceptions to input stream.
141      */
142     public void exceptionCaught(IoSession session, Throwable JavaDoc cause) {
143         final IoSessionInputStream in = (IoSessionInputStream) session
144                 .getAttribute(KEY_IN);
145
146         IOException JavaDoc e = null;
147         if (cause instanceof StreamIoException) {
148             e = (IOException JavaDoc) cause.getCause();
149         } else if (cause instanceof IOException JavaDoc) {
150             e = (IOException JavaDoc) cause;
151         }
152
153         if (e != null && in != null) {
154             in.throwException(e);
155         } else {
156             SessionLog.warn(session, "Unexpected exception.", cause);
157             session.close();
158         }
159     }
160
161     /**
162      * Handles read timeout.
163      */
164     public void sessionIdle(IoSession session, IdleStatus status) {
165         if (status == IdleStatus.READER_IDLE) {
166             throw new StreamIoException(new SocketTimeoutException JavaDoc(
167                     "Read timeout"));
168         }
169     }
170
171     private static class StreamIoException extends RuntimeException JavaDoc {
172         private static final long serialVersionUID = 3976736960742503222L;
173
174         public StreamIoException(IOException JavaDoc cause) {
175             super(cause);
176         }
177     }
178 }
179
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