KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > mina > filter > codec > support > SimpleProtocolEncoderOutput


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.filter.codec.support;
21
22 import java.util.LinkedList JavaDoc;
23 import java.util.Queue JavaDoc;
24
25 import org.apache.mina.common.ByteBuffer;
26 import org.apache.mina.common.WriteFuture;
27 import org.apache.mina.filter.codec.ProtocolEncoderOutput;
28
29 /**
30  * A {@link ProtocolEncoderOutput} based on queue.
31  *
32  * @author The Apache Directory Project (mina-dev@directory.apache.org)
33  * @version $Rev: 555855 $, $Date: 2007-07-13 12:19:00 +0900 (금, 13 7월 2007) $
34  */
35 public abstract class SimpleProtocolEncoderOutput implements
36         ProtocolEncoderOutput {
37     private final Queue JavaDoc<ByteBuffer> bufferQueue = new LinkedList JavaDoc<ByteBuffer>();
38
39     public SimpleProtocolEncoderOutput() {
40     }
41
42     public Queue JavaDoc<ByteBuffer> getBufferQueue() {
43         return bufferQueue;
44     }
45
46     public void write(ByteBuffer buf) {
47         bufferQueue.add(buf);
48     }
49
50     public void mergeAll() {
51         int sum = 0;
52         final int size = bufferQueue.size();
53
54         if (size < 2) {
55             // no need to merge!
56 return;
57         }
58
59         // Get the size of merged BB
60 for (Object JavaDoc o : bufferQueue) {
61             sum += ((ByteBuffer) o).remaining();
62         }
63
64         // Allocate a new BB that will contain all fragments
65 ByteBuffer newBuf = ByteBuffer.allocate(sum);
66
67         // and merge all.
68 for (;;) {
69             ByteBuffer buf = bufferQueue.poll();
70             if (buf == null) {
71                 break;
72             }
73
74             newBuf.put(buf);
75             buf.release();
76         }
77
78         // Push the new buffer finally.
79 newBuf.flip();
80         bufferQueue.offer(newBuf);
81     }
82
83     public WriteFuture flush() {
84         Queue JavaDoc<ByteBuffer> bufferQueue = this.bufferQueue;
85         WriteFuture future = null;
86         if (bufferQueue.isEmpty()) {
87             return null;
88         } else {
89             for (;;) {
90                 ByteBuffer buf = bufferQueue.poll();
91                 if (buf == null) {
92                     break;
93                 }
94
95                 // Flush only when the buffer has remaining.
96 if (buf.hasRemaining()) {
97                     future = doFlush(buf);
98                 }
99             }
100         }
101
102         return future;
103     }
104
105     protected abstract WriteFuture doFlush(ByteBuffer buf);
106 }
Popular Tags