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/*
* JPPF.
* Copyright (C) 2005-2015 JPPF Team.
* http://www.jppf.org
*
* Licensed 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 org.jppf.utils.pooling;
import java.util.concurrent.atomic.AtomicInteger;
/**
* An extension of {@link AbstractObjectPoolQueue} which specifies a maximum size for the pool.
* In this implementation, objects are still created dynamically if the pool is empty, however
* the put(T) method does not return an element to the backing queue if the pool size >= max size.
*
the {@link #size()} method is also overriden to provide results in constant time insteat of O(n) in
* the super class, since it is used frequently when comparing current pool size with the max size.
* @param the type of the elements in the pool.
* @author Laurent Cohen
*/
public abstract class AbstractBoundedObjectPoolQueue extends AbstractObjectPoolQueue
{
/**
* The current size of the pool.
*/
protected AtomicInteger size = new AtomicInteger(0);
/**
* The pool max size.
*/
protected final int maxSize;
/**
* Initialize this pool with the specified maximum size.
* @param maxSize the pool max size.
*/
public AbstractBoundedObjectPoolQueue(final int maxSize)
{
this.maxSize = maxSize;
}
@Override
public T get()
{
T t = queue.poll();
if (t != null) size.decrementAndGet();
else t = create();
return t;
}
@Override
public void put(final T t)
{
if (size.get() < maxSize)
{
size.incrementAndGet();
queue.offer(t);
}
}
@Override
public int size()
{
return size.get();
}
}