io.netty.channel.ChannelPromiseAggregator Maven / Gradle / Ivy
/*
* Copyright 2012 The Netty Project
*
* The Netty Project licenses this file 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 "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 io.netty.channel;
import java.util.LinkedHashSet;
import java.util.Set;
/**
* Class which is used to consolidate multiple channel futures into one, by
* listening to the individual futures and producing an aggregated result
* (success/failure) when all futures have completed.
*/
public final class ChannelPromiseAggregator implements ChannelFutureListener {
private final ChannelPromise aggregatePromise;
private Set pendingPromises;
public ChannelPromiseAggregator(ChannelPromise aggregatePromise) {
if (aggregatePromise == null) {
throw new NullPointerException("aggregatePromise");
}
this.aggregatePromise = aggregatePromise;
}
/**
* Add the given {@link ChannelPromise}s to the aggregator.
*/
public ChannelPromiseAggregator add(ChannelPromise... promises) {
if (promises == null) {
throw new NullPointerException("promises");
}
if (promises.length == 0) {
return this;
}
synchronized (this) {
if (pendingPromises == null) {
int size;
if (promises.length > 1) {
size = promises.length;
} else {
size = 2;
}
pendingPromises = new LinkedHashSet(size);
}
for (ChannelPromise p: promises) {
if (p == null) {
continue;
}
pendingPromises.add(p);
p.addListener(this);
}
}
return this;
}
@Override
public synchronized void operationComplete(ChannelFuture future) throws Exception {
if (pendingPromises == null) {
aggregatePromise.setSuccess();
} else {
pendingPromises.remove(future);
if (!future.isSuccess()) {
aggregatePromise.setFailure(future.cause());
for (ChannelPromise pendingFuture : pendingPromises) {
pendingFuture.setFailure(future.cause());
}
} else {
if (pendingPromises.isEmpty()) {
aggregatePromise.setSuccess();
}
}
}
}
}