src/main/java/com/amazon/carbonado/util/WeakReentrantReadWriteLockPool.java


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/*
 * Copyright 2006-2010 Amazon Technologies, Inc. or its affiliates.
 * Amazon, Amazon.com and Carbonado are trademarks or registered trademarks
 * of Amazon Technologies, Inc. or its affiliates.  All rights reserved.
 *
 * 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 com.amazon.carbonado.util;

import java.util.concurrent.locks.ReentrantReadWriteLock;

/**
 * A concurrent pool of weakly referenced {@link ReentrantReadWriteLock}
 * instances mapped by key. Locks are created (and recreated) as needed.
 *
 * @author Brian S O'Neill
 * @since 1.2
 */
class WeakReentrantReadWriteLockPool<K>
    extends AbstractWeakPool<K, ReentrantReadWriteLock, RuntimeException>
{
    private final boolean mFair;

    public WeakReentrantReadWriteLockPool() {
        this(false);
    }

    public WeakReentrantReadWriteLockPool(boolean fair) {
        mFair = fair;
    }

    @Override
    protected ReentrantReadWriteLock create(K key) {
        return new ReentrantReadWriteLock(mFair);
    }
}