de.intarsys.tools.concurrent.SynchronousQueuedExecutorService Maven / Gradle / Ivy
Show all versions of isrt Show documentation
/*
* Copyright (c) 2007, intarsys consulting GmbH
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* - Neither the name of intarsys nor the names of its contributors may be used
* to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
package de.intarsys.tools.concurrent;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.AbstractExecutorService;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.TimeUnit;
/**
* An {@link ExecutorService} that enqueues all commmands.
*
* The commands are performed synchronously upon calling "drain".
*/
public class SynchronousQueuedExecutorService extends AbstractExecutorService {
volatile private boolean shutdown = false;
volatile private boolean terminated = false;
private List queue = new ArrayList();
private Object lock = new Object();
/*
* (non-Javadoc)
*
* @see java.util.concurrent.ExecutorService#awaitTermination(long,
* java.util.concurrent.TimeUnit)
*/
public boolean awaitTermination(long timeout, TimeUnit unit)
throws InterruptedException {
return true;
}
public void drain() {
List tempQueue;
synchronized (lock) {
tempQueue = new ArrayList(queue);
queue.clear();
}
for (Iterator it = tempQueue.iterator(); it.hasNext();) {
Runnable command = (Runnable) it.next();
command.run();
}
}
/*
* (non-Javadoc)
*
* @see java.util.concurrent.Executor#execute(java.lang.Runnable)
*/
public void execute(Runnable command) {
synchronized (lock) {
if (shutdown || terminated) {
return;
}
queue.add(command);
}
}
/*
* (non-Javadoc)
*
* @see java.util.concurrent.ExecutorService#isShutdown()
*/
public boolean isShutdown() {
synchronized (lock) {
return shutdown;
}
}
/*
* (non-Javadoc)
*
* @see java.util.concurrent.ExecutorService#isTerminated()
*/
public boolean isTerminated() {
synchronized (lock) {
return terminated;
}
}
/*
* (non-Javadoc)
*
* @see java.util.concurrent.ExecutorService#shutdown()
*/
public void shutdown() {
synchronized (lock) {
shutdown = true;
terminated = true;
}
}
/*
* (non-Javadoc)
*
* @see java.util.concurrent.ExecutorService#shutdownNow()
*/
public List shutdownNow() {
synchronized (lock) {
shutdown = true;
terminated = true;
return new ArrayList(queue);
}
}
}