- /*
- * Copyright 2002-2004 The Apache Software Foundation
- *
- * Licensed 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.
- *
- */
-
- package org.apache.tools.ant.util;
-
- import java.util.Enumeration;
- import java.util.Vector;
-
- /**
- * Generalization of <code>ExecuteWatchdog</code>
- *
- * @since Ant 1.5
- *
- * @see org.apache.tools.ant.taskdefs.ExecuteWatchdog
- *
- */
- public class Watchdog implements Runnable {
-
- private Vector observers = new Vector(1);
- private long timeout = -1;
- private boolean stopped = false;
-
- public Watchdog(long timeout) {
- if (timeout < 1) {
- throw new IllegalArgumentException("timeout lesser than 1.");
- }
- this.timeout = timeout;
- }
-
- public void addTimeoutObserver(TimeoutObserver to) {
- observers.addElement(to);
- }
-
- public void removeTimeoutObserver(TimeoutObserver to) {
- observers.removeElement(to);
- }
-
- protected final void fireTimeoutOccured() {
- Enumeration e = observers.elements();
- while (e.hasMoreElements()) {
- ((TimeoutObserver) e.nextElement()).timeoutOccured(this);
- }
- }
-
- public synchronized void start() {
- stopped = false;
- Thread t = new Thread(this, "WATCHDOG");
- t.setDaemon(true);
- t.start();
- }
-
- public synchronized void stop() {
- stopped = true;
- notifyAll();
- }
-
- public synchronized void run() {
- final long until = System.currentTimeMillis() + timeout;
- long now;
- while (!stopped && until > (now = System.currentTimeMillis())) {
- try {
- wait(until - now);
- } catch (InterruptedException e) {
- }
- }
- if (!stopped) {
- fireTimeoutOccured();
- }
- }
-
- }