org.apache.mina.core.future.CompositeIoFuture Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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
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* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
package org.apache.mina.core.future;
import java.util.concurrent.atomic.AtomicInteger;
import org.apache.mina.core.IoUtil;
/**
* An {@link IoFuture} of {@link IoFuture}s. It is useful when you want to
* get notified when all {@link IoFuture}s are complete. It is not recommended
* to use {@link CompositeIoFuture} if you just want to wait for all futures.
* In that case, please use {@link IoUtil#await(Iterable)} instead
* for better performance.
*
* @author Apache MINA Project
*
* @param the type of the child futures.
*/
public class CompositeIoFuture extends DefaultIoFuture {
/** A listener */
private final NotifyingListener listener = new NotifyingListener();
/** A thread safe counter that is used to keep a track of the notified futures */
private final AtomicInteger unnotified = new AtomicInteger();
/** A flag set to TRUE when all the future have been added to the list */
private volatile boolean constructionFinished;
/**
* Creates a new CompositeIoFuture instance
*
* @param children The list of internal futures
*/
public CompositeIoFuture(Iterable children) {
super(null);
for (E child : children) {
child.addListener(listener);
unnotified.incrementAndGet();
}
constructionFinished = true;
if (unnotified.get() == 0) {
setValue(true);
}
}
private class NotifyingListener implements IoFutureListener {
/**
* {@inheritDoc}
*/
@Override
public void operationComplete(IoFuture future) {
if (unnotified.decrementAndGet() == 0 && constructionFinished) {
setValue(true);
}
}
}
}