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 java.io.IOException;
022
023import org.apache.hadoop.hbase.HConstants;
024import org.apache.hadoop.hbase.client.RegionInfo;
025import org.apache.hadoop.hbase.master.MasterServices;
026import org.apache.yetus.audience.InterfaceAudience;
027import org.slf4j.Logger;
028import org.slf4j.LoggerFactory;
029
030/**
031 * Normalization plan to merge regions (smallest region in the table with its smallest neighbor).
032 */
033@InterfaceAudience.Private
034public class MergeNormalizationPlan implements NormalizationPlan {
035  private static final Logger LOG = LoggerFactory.getLogger(MergeNormalizationPlan.class.getName());
036
037  private final RegionInfo firstRegion;
038  private final RegionInfo secondRegion;
039
040  public MergeNormalizationPlan(RegionInfo firstRegion, RegionInfo secondRegion) {
041    this.firstRegion = firstRegion;
042    this.secondRegion = secondRegion;
043  }
044
045  /**
046   * {@inheritDoc}
047   */
048  @Override
049  public long submit(MasterServices masterServices) throws IOException {
050    LOG.info("Executing merging normalization plan: " + this);
051    // Do not use force=true as corner cases can happen, non adjacent regions,
052    // merge with a merged child region with no GC done yet, it is going to
053    // cause all different issues.
054    return masterServices
055      .mergeRegions(new RegionInfo[] { firstRegion, secondRegion }, false, HConstants.NO_NONCE,
056        HConstants.NO_NONCE);
057  }
058
059  @Override
060  public PlanType getType() {
061    return PlanType.MERGE;
062  }
063
064  RegionInfo getFirstRegion() {
065    return firstRegion;
066  }
067
068  RegionInfo getSecondRegion() {
069    return secondRegion;
070  }
071
072  @Override
073  public String toString() {
074    return "MergeNormalizationPlan{" +
075      "firstRegion=" + firstRegion +
076      ", secondRegion=" + secondRegion +
077      '}';
078  }
079
080}