001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020package org.apache.mina.core.future; 021 022import java.util.concurrent.atomic.AtomicInteger; 023 024import org.apache.mina.core.IoUtil; 025 026/** 027 * An {@link IoFuture} of {@link IoFuture}s. It is useful when you want to 028 * get notified when all {@link IoFuture}s are complete. It is not recommended 029 * to use {@link CompositeIoFuture} if you just want to wait for all futures. 030 * In that case, please use {@link IoUtil#await(Iterable)} instead 031 * for better performance. 032 * 033 * @author <a href="http://mina.apache.org">Apache MINA Project</a> 034 * 035 * @param <E> the type of the child futures. 036 */ 037public class CompositeIoFuture<E extends IoFuture> extends DefaultIoFuture { 038 039 private final NotifyingListener listener = new NotifyingListener(); 040 041 private final AtomicInteger unnotified = new AtomicInteger(); 042 043 private volatile boolean constructionFinished; 044 045 public CompositeIoFuture(Iterable<E> children) { 046 super(null); 047 048 for (E f : children) { 049 f.addListener(listener); 050 unnotified.incrementAndGet(); 051 } 052 053 constructionFinished = true; 054 if (unnotified.get() == 0) { 055 setValue(true); 056 } 057 } 058 059 private class NotifyingListener implements IoFutureListener<IoFuture> { 060 public void operationComplete(IoFuture future) { 061 if (unnotified.decrementAndGet() == 0 && constructionFinished) { 062 setValue(true); 063 } 064 } 065 } 066}