/*
* Copyright (c) 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017 David Berkman
*
* This file is part of the SmallMind Code Project.
*
* The SmallMind Code Project is free software, you can redistribute
* it and/or modify it under either, at your discretion...
*
* 1) The terms of GNU Affero General Public License as published by the
* Free Software Foundation, either version 3 of the License, or (at
* your option) any later version.
*
* ...or...
*
* 2) The terms of the Apache License, Version 2.0.
*
* The SmallMind Code Project is distributed in the hope that it will
* be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License or Apache License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* and the Apache License along with the SmallMind Code Project. If not, see
* <http://www.gnu.org/licenses/> or <http://www.apache.org/licenses/LICENSE-2.0>.
*
* Additional permission under the GNU Affero GPL version 3 section 7
* ------------------------------------------------------------------
* If you modify this Program, or any covered work, by linking or
* combining it with other code, such other code is not for that reason
* alone subject to any of the requirements of the GNU Affero GPL
* version 3.
*/
package org.smallmind.web.reverse;
import java.nio.channels.SocketChannel;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import org.smallmind.scribe.pen.LoggerManager;
public class ProxyExecutor {
private final CountDownLatch exitLatch;
private final ExecutionWorker[] workers;
private final int concurrencyLimit;
public ProxyExecutor (int concurrencyLimit) {
this.concurrencyLimit = concurrencyLimit;
exitLatch = new CountDownLatch(concurrencyLimit);
workers = new ExecutionWorker[concurrencyLimit];
for (int index = 0; index < workers.length; index++) {
new Thread(workers[index] = new ExecutionWorker()).start();
}
}
public void execute (SocketChannel sourceChannel, Runnable runnable) {
workers[sourceChannel.hashCode() % concurrencyLimit].execute(runnable);
}
public void shutdown () {
for (ExecutionWorker worker : workers) {
worker.abort();
}
try {
exitLatch.await();
} catch (InterruptedException interruptedException) {
LoggerManager.getLogger(ProxyExecutor.class).error(interruptedException);
}
}
private class ExecutionWorker implements Runnable {
private AtomicBoolean stopped = new AtomicBoolean(false);
private LinkedBlockingQueue<Runnable> runnableQueue = new LinkedBlockingQueue<>();
private void abort () {
stopped.compareAndSet(false, true);
}
private void execute (Runnable runnable) {
runnableQueue.add(runnable);
}
@Override
public void run () {
try {
while (!stopped.get()) {
Runnable runnable;
if ((runnable = runnableQueue.poll(1, TimeUnit.SECONDS)) != null) {
runnable.run();
}
}
} catch (InterruptedException interruptedException) {
LoggerManager.getLogger(ProxyExecutor.class).error(interruptedException);
} finally {
exitLatch.countDown();
}
}
}
}