org.apache.qpid.bytebuffer.PooledByteBufferRef Maven / Gradle / Ivy
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*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.qpid.bytebuffer;
import java.nio.ByteBuffer;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
class PooledByteBufferRef implements ByteBufferRef
{
private static final AtomicIntegerFieldUpdater REF_COUNT = AtomicIntegerFieldUpdater.newUpdater(PooledByteBufferRef.class, "_refCount");
private final ByteBuffer _buffer;
private volatile int _refCount;
PooledByteBufferRef(final ByteBuffer buffer)
{
_buffer = buffer;
}
@Override
public void incrementRef()
{
if(REF_COUNT.get(this) >= 0)
{
REF_COUNT.incrementAndGet(this);
}
}
@Override
public void decrementRef()
{
if(REF_COUNT.get(this) > 0 && REF_COUNT.decrementAndGet(this) == 0)
{
QpidByteBuffer.returnToPool(_buffer);
}
}
@Override
public ByteBuffer getBuffer()
{
return _buffer.duplicate();
}
@Override
public void removeFromPool()
{
REF_COUNT.set(this, Integer.MIN_VALUE/2);
}
}