content: package org.apache.lucene.store;
  
  /**
   * 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.
   */
  
  import java.io.IOException;
  
  /**
   * Use this {@link LockFactory} to disable locking entirely.
   * Only one instance of this lock is created.  You should call {@link
   * #getNoLockFactory()} to get the instance.
   *
   * @see LockFactory
   */
  
  public class NoLockFactory extends LockFactory {
  
    // Single instance returned whenever makeLock is called.
    private static NoLock singletonLock = new NoLock();
    private static NoLockFactory singleton = new NoLockFactory();
    
    /**
     * @deprecated This constructor was not intended to be public and should not be used.
     *  It will be made private in Lucene 4.0
     * @see #getNoLockFactory()
     */
    // make private in 4.0!
    @Deprecated
    public NoLockFactory() {}
  
    public static NoLockFactory getNoLockFactory() {
      return singleton;
    }
  
    @Override
    public Lock makeLock(String lockName) {
      return singletonLock;
    }
  
    @Override
    public void clearLock(String lockName) {}
  }
  
  class NoLock extends Lock {
    @Override
    public boolean obtain() throws IOException {
      return true;
    }
  
    @Override
    public void release() {
    }
  
    @Override
    public boolean isLocked() {
      return false;
    }
  
    @Override
    public String toString() {
      return "NoLock";
    }
  }
  