001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.zookeeper;
019
020import org.apache.yetus.audience.InterfaceAudience;
021import org.apache.zookeeper.WatchedEvent;
022import org.apache.zookeeper.Watcher;
023
024/**
025 * An empty ZooKeeper watcher
026 */
027@InterfaceAudience.Private
028public final class EmptyWatcher implements Watcher {
029  // Used in this package but also by tests so needs to be public
030  public static final EmptyWatcher instance = new EmptyWatcher();
031
032  private EmptyWatcher() {
033  }
034
035  @Override
036  public void process(WatchedEvent event) {
037  }
038}