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Handful shortcuts for Java programming, Java 7 compatible.

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/*******************************************************************************
 * Copyright (C) 2009, 2015, Danilo Pianini and contributors
 * listed in the project's build.gradle or pom.xml file.
 *
 * This file is distributed under the terms of the Apache License, version 2.0
 *******************************************************************************/
package org.danilopianini.concurrency;

import java.util.concurrent.Semaphore;

/**
 * This class implements a non-reentrant ReadWriteLock.
 * 
 */
public class FastReadWriteLock {

    private final Semaphore lock = new Semaphore(Integer.MAX_VALUE);

    /**
     * Acquire a read lock. Blocks until a read lock is available
     */
    public void read() {
        lock.acquireUninterruptibly();
    }

    /**
     * Acquire a write lock. Blocks until a write lock is available
     */
    public void write() {
        lock.acquireUninterruptibly(Integer.MAX_VALUE);
    }

    /**
     * Signals that the operation is done.
     */
    public void release() {
        if (lock.availablePermits() == 0) {
            lock.release(Integer.MAX_VALUE);
        } else {
            lock.release();
        }
    }
}