001/**
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 *     http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019package org.apache.hadoop.hbase.master.normalizer;
020
021import org.apache.yetus.audience.InterfaceAudience;
022import org.apache.hadoop.hbase.client.Admin;
023import org.apache.hadoop.hbase.master.normalizer.NormalizationPlan.PlanType;
024
025/**
026 * Plan which signifies that no normalization is required,
027 * or normalization of this table isn't allowed, this is singleton.
028 */
029@InterfaceAudience.Private
030public final class EmptyNormalizationPlan implements NormalizationPlan {
031  private static final EmptyNormalizationPlan instance = new EmptyNormalizationPlan();
032
033  private EmptyNormalizationPlan() {
034  }
035
036  /**
037   * @return singleton instance
038   */
039  public static EmptyNormalizationPlan getInstance(){
040    return instance;
041  }
042
043  /**
044   * No-op for empty plan.
045   */
046  @Override
047  public void execute(Admin admin) {
048  }
049
050  @Override
051  public PlanType getType() {
052    return PlanType.NONE;
053  }
054}