KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > tomcat > util > net > LeaderFollowerWorkerThread


1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one or more
3  * contributor license agreements. See the NOTICE file distributed with
4  * this work for additional information regarding copyright ownership.
5  * The ASF licenses this file to You under the Apache License, Version 2.0
6  * (the "License"); you may not use this file except in compliance with
7  * the License. You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17
18 package org.apache.tomcat.util.net;
19
20 import java.net.Socket JavaDoc;
21 import org.apache.tomcat.util.threads.ThreadPoolRunnable;
22
23 /*
24  * I switched the threading model here.
25  *
26  * We used to have a "listener" thread and a "connection"
27  * thread, this results in code simplicity but also a needless
28  * thread switch.
29  *
30  * Instead I am now using a pool of threads, all the threads are
31  * simmetric in their execution and no thread switch is needed.
32  */
33 class LeaderFollowerWorkerThread implements ThreadPoolRunnable {
34     /* This is not a normal Runnable - it gets attached to an existing
35        thread, runs and when run() ends - the thread keeps running.
36
37        It's better to keep the name ThreadPoolRunnable - avoid confusion.
38        We also want to use per/thread data and avoid sync wherever possible.
39     */
40     PoolTcpEndpoint endpoint;
41     
42     public LeaderFollowerWorkerThread(PoolTcpEndpoint endpoint) {
43         this.endpoint = endpoint;
44     }
45
46     public Object JavaDoc[] getInitData() {
47         // no synchronization overhead, but 2 array access
48 Object JavaDoc obj[]=new Object JavaDoc[2];
49         obj[1]= endpoint.getConnectionHandler().init();
50         obj[0]=new TcpConnection();
51         return obj;
52     }
53     
54     public void runIt(Object JavaDoc perThrData[]) {
55
56         // Create per-thread cache
57 if (endpoint.isRunning()) {
58
59             // Loop if endpoint is paused
60 while (endpoint.isPaused()) {
61                 try {
62                     Thread.sleep(1000);
63                 } catch (InterruptedException JavaDoc e) {
64                     // Ignore
65 }
66             }
67
68             // Accept a new connection
69 Socket JavaDoc s = null;
70             try {
71                 s = endpoint.acceptSocket();
72             } finally {
73                 // Continue accepting on another thread...
74 if (endpoint.isRunning()) {
75                     endpoint.tp.runIt(this);
76                 }
77             }
78
79             // Process the connection
80 if (null != s) {
81                 endpoint.processSocket(s, (TcpConnection) perThrData[0], (Object JavaDoc[]) perThrData[1]);
82             }
83
84         }
85     }
86     
87 }
88
Popular Tags