/*
* $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 $
* $Revision: 480424 $
* $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $
*
* ====================================================================
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.commons.httpclient.util;
/**
* <p>
* Executes a task with a specified timeout.
* </p>
* @author Ortwin Glueck
* @author <a href="mailto:[email protected]">Mike Bowler</a>
* @version $Revision: 480424 $
* @since 2.0
*/
public final class TimeoutController {
/**
* Do not instantiate objects of this class. Methods are static.
*/
private TimeoutController() {
}
/**
* Executes <code>task</code>. Waits for <code>timeout</code>
* milliseconds for the task to end and returns. If the task does not return
* in time, the thread is interrupted and an Exception is thrown.
* The caller should override the Thread.interrupt() method to something that
* quickly makes the thread die or use Thread.isInterrupted().
* @param task The thread to execute
* @param timeout The timeout in milliseconds. 0 means to wait forever.
* @throws TimeoutException if the timeout passes and the thread does not return.
*/
public static void execute(Thread task, long timeout) throws TimeoutException {
task.start();
try {
task.join(timeout);
} catch (InterruptedException e) {
/* if somebody interrupts us he knows what he is doing */
}
if (task.isAlive()) {
task.interrupt();
throw new TimeoutException();
}
}
/**
* Executes <code>task</code> in a new deamon Thread and waits for the timeout.
* @param task The task to execute
* @param timeout The timeout in milliseconds. 0 means to wait forever.
* @throws TimeoutException if the timeout passes and the thread does not return.
*/
public static void execute(Runnable task, long timeout) throws TimeoutException {
Thread t = new Thread(task, "Timeout guard");
t.setDaemon(true);
execute(t, timeout);
}
/**
* Signals that the task timed out.
*/
public static class TimeoutException extends Exception {
/** Create an instance */
public TimeoutException() {
}
}
}
|