content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.master.block;
  
  import java.util.concurrent.atomic.AtomicLong;
  import javax.annotation.concurrent.ThreadSafe;
  
  /**
   * This class generates unique block container ids.
   */
  @ThreadSafe
  public final class BlockContainerIdGenerator implements ContainerIdGenerable {
  
    private final AtomicLong mNextContainerId;
  
    /**
     * Creates a new instance of {@link BlockContainerIdGenerator}.
     */
    public BlockContainerIdGenerator() {
      mNextContainerId = new AtomicLong(0);
    }
  
    @Override
    public long getNewContainerId() {
      return mNextContainerId.getAndIncrement();
    }
  
    /**
     * @return a unique block container id, and is used
     */
    public long getNextContainerId() {
      return mNextContainerId.get();
    }
  
    /**
     * @return the next container id
     */
    public long peekNewContainerId() {
      return mNextContainerId.get();
    }
  
    /**
     * @param id the next container id to use
     */
    public void setNextContainerId(long id) {
      mNextContainerId.set(id);
    }
  }
  