001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.commons.concurrent;
018
019import java.util.concurrent.locks.*;
020
021/**
022 * An extension of {@link ReentrantReadWriteLock} with convenience methods for creating
023 * auto-closeable locks.
024 */
025public class SimpleReadWriteLock extends ReentrantReadWriteLock {
026   private static final long serialVersionUID = 1L;
027   /**
028    * A no-op lock.
029    */
030   public static SimpleReadWriteLock NO_OP = new SimpleReadWriteLock() {
031      private static final long serialVersionUID = 1L;
032
033      @Override
034      public SimpleLock read() {
035         return SimpleLock.NO_OP;
036      }
037
038      @Override
039      public SimpleLock write() {
040         return SimpleLock.NO_OP;
041      }
042   };
043
044   /**
045    * Constructor.
046    */
047   public SimpleReadWriteLock() {}
048
049   /**
050    * Constructor
051    *
052    * @param fair <jk>true</jk> if this lock should use a fair ordering policy.
053    */
054   public SimpleReadWriteLock(boolean fair) {
055      super(fair);
056   }
057
058   /**
059    * Construct a read lock.
060    *
061    * @return A new closeable read lock.
062    */
063   public SimpleLock read() {
064      return new SimpleLock(readLock());
065   }
066
067   /**
068    * Construct a write lock.
069    *
070    * @return A new closeable write lock.
071    */
072   public SimpleLock write() {
073      return new SimpleLock(writeLock());
074   }
075}