org.glassfish.grizzly.threadpool.FixedThreadPool Maven / Gradle / Ivy
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package org.glassfish.grizzly.threadpool;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.RejectedExecutionException;
import org.glassfish.grizzly.utils.DataStructures;
/**
* Minimalistic fixed thread pool to allow for nice scalability if a
* good Queue impl is used.
*
* @author gustav trede
*/
public class FixedThreadPool extends AbstractThreadPool {
protected final BlockingQueue workQueue;
public FixedThreadPool(ThreadPoolConfig config) {
super(config);
this.workQueue = config.getQueue() != null ?
(BlockingQueue) config.getQueue() :
(BlockingQueue) config.setQueue(
DataStructures.getLTQInstance(Runnable.class)).getQueue();
int poolSize = config.getMaxPoolSize();
synchronized (stateLock) {
while (poolSize-- > 0) {
doStartWorker();
}
}
ProbeNotifier.notifyThreadPoolStarted(this);
super.onMaxNumberOfThreadsReached();
}
/**
* Must hold statelock while calling this method.
*/
private void doStartWorker() {
startWorker(new BasicWorker());
}
@Override
public void execute(Runnable command) {
if (running) {
if (workQueue.offer(command)) {
// doublecheck the pool is still running
if (!running && workQueue.remove(command)) {
throw new RejectedExecutionException("ThreadPool is not running");
}
onTaskQueued(command);
return;
}
onTaskQueueOverflow();
return;
}
throw new RejectedExecutionException("ThreadPool is not running");
}
private final class BasicWorker extends Worker {
@Override
protected final Runnable getTask() throws InterruptedException {
return workQueue.take();
}
}
}