01: /*
02: * $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/util/TimeoutController.java,v 1.6 2004/04/18 23:51:38 jsdever Exp $
03: * $Revision: 480424 $
04: * $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $
05: *
06: * ====================================================================
07: *
08: * Licensed to the Apache Software Foundation (ASF) under one or more
09: * contributor license agreements. See the NOTICE file distributed with
10: * this work for additional information regarding copyright ownership.
11: * The ASF licenses this file to You under the Apache License, Version 2.0
12: * (the "License"); you may not use this file except in compliance with
13: * the License. You may obtain a copy of the License at
14: *
15: * http://www.apache.org/licenses/LICENSE-2.0
16: *
17: * Unless required by applicable law or agreed to in writing, software
18: * distributed under the License is distributed on an "AS IS" BASIS,
19: * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
20: * See the License for the specific language governing permissions and
21: * limitations under the License.
22: * ====================================================================
23: *
24: * This software consists of voluntary contributions made by many
25: * individuals on behalf of the Apache Software Foundation. For more
26: * information on the Apache Software Foundation, please see
27: * <http://www.apache.org/>.
28: *
29: */
30:
31: package org.apache.commons.httpclient.util;
32:
33: /**
34: * <p>
35: * Executes a task with a specified timeout.
36: * </p>
37: * @author Ortwin Glueck
38: * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
39: * @version $Revision: 480424 $
40: * @since 2.0
41: */
42: public final class TimeoutController {
43:
44: /**
45: * Do not instantiate objects of this class. Methods are static.
46: */
47: private TimeoutController() {
48: }
49:
50: /**
51: * Executes <code>task</code>. Waits for <code>timeout</code>
52: * milliseconds for the task to end and returns. If the task does not return
53: * in time, the thread is interrupted and an Exception is thrown.
54: * The caller should override the Thread.interrupt() method to something that
55: * quickly makes the thread die or use Thread.isInterrupted().
56: * @param task The thread to execute
57: * @param timeout The timeout in milliseconds. 0 means to wait forever.
58: * @throws TimeoutException if the timeout passes and the thread does not return.
59: */
60: public static void execute(Thread task, long timeout)
61: throws TimeoutException {
62: task.start();
63: try {
64: task.join(timeout);
65: } catch (InterruptedException e) {
66: /* if somebody interrupts us he knows what he is doing */
67: }
68: if (task.isAlive()) {
69: task.interrupt();
70: throw new TimeoutException();
71: }
72: }
73:
74: /**
75: * Executes <code>task</code> in a new deamon Thread and waits for the timeout.
76: * @param task The task to execute
77: * @param timeout The timeout in milliseconds. 0 means to wait forever.
78: * @throws TimeoutException if the timeout passes and the thread does not return.
79: */
80: public static void execute(Runnable task, long timeout)
81: throws TimeoutException {
82: Thread t = new Thread(task, "Timeout guard");
83: t.setDaemon(true);
84: execute(t, timeout);
85: }
86:
87: /**
88: * Signals that the task timed out.
89: */
90: public static class TimeoutException extends Exception {
91: /** Create an instance */
92: public TimeoutException() {
93: }
94: }
95: }
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