/*
 * $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;


Executes a task with a specified timeout.

Author:
Ortwin Glueck, Mike Bowler
Version:
$Revision: 480424 $
Since:
2.0/**
 * <p>
 * Executes a task with a specified timeout.
 * </p>
 * @author Ortwin Glueck
 * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
 * @version $Revision: 480424 $
 * @since 2.0
 */
public final class TimeoutController {

    
Do not instantiate objects of this class. Methods are static.
/**
     * Do not instantiate objects of this class. Methods are static.
     */
    private TimeoutController() {
    }

    
Executes task. Waits for timeout
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().
Params:
task – The thread to execute
timeout – The timeout in milliseconds. 0 means to wait forever.
Throws:
TimeoutException – if the timeout passes and the thread does not return./**
     * 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 task in a new deamon Thread and waits for the timeout.
Params:
task – The task to execute
timeout – The timeout in milliseconds. 0 means to wait forever.
Throws:
TimeoutException – if the timeout passes and the thread does not return./**
     * 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.
/**
     * Signals that the task timed out.
     */
    public static class TimeoutException extends Exception {
        
Create an instance /** Create an instance */
        public TimeoutException() {
        }
    }
}