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.util.Collections;
022import java.util.LinkedList;
023import java.util.List;
024import org.apache.commons.lang3.builder.EqualsBuilder;
025import org.apache.commons.lang3.builder.HashCodeBuilder;
026import org.apache.commons.lang3.builder.ToStringBuilder;
027import org.apache.commons.lang3.builder.ToStringStyle;
028import org.apache.hadoop.hbase.client.RegionInfo;
029import org.apache.hadoop.hbase.master.MasterServices;
030import org.apache.yetus.audience.InterfaceAudience;
031import org.apache.hbase.thirdparty.com.google.common.base.Preconditions;
032
033/**
034 * Normalization plan to merge adjacent regions. As with any call to
035 * {@link MasterServices#mergeRegions(RegionInfo[], boolean, long, long)}
036 * with {@code forcible=false}, Region order and adjacency are important. It's the caller's
037 * responsibility to ensure the provided parameters are ordered according to the
038 * {code mergeRegions} method requirements.
039 */
040@InterfaceAudience.Private
041final class MergeNormalizationPlan implements NormalizationPlan {
042
043  private final List<NormalizationTarget> normalizationTargets;
044
045  private MergeNormalizationPlan(List<NormalizationTarget> normalizationTargets) {
046    Preconditions.checkNotNull(normalizationTargets);
047    Preconditions.checkState(normalizationTargets.size() >= 2,
048      "normalizationTargets.size() must be >= 2 but was %s", normalizationTargets.size());
049    this.normalizationTargets = Collections.unmodifiableList(normalizationTargets);
050  }
051
052  @Override
053  public PlanType getType() {
054    return PlanType.MERGE;
055  }
056
057  public List<NormalizationTarget> getNormalizationTargets() {
058    return normalizationTargets;
059  }
060
061  @Override
062  public String toString() {
063    return new ToStringBuilder(this, ToStringStyle.SHORT_PREFIX_STYLE)
064      .append("normalizationTargets", normalizationTargets)
065      .toString();
066  }
067
068  @Override
069  public boolean equals(Object o) {
070    if (this == o) {
071      return true;
072    }
073
074    if (o == null || getClass() != o.getClass()) {
075      return false;
076    }
077
078    MergeNormalizationPlan that = (MergeNormalizationPlan) o;
079
080    return new EqualsBuilder()
081      .append(normalizationTargets, that.normalizationTargets)
082      .isEquals();
083  }
084
085  @Override
086  public int hashCode() {
087    return new HashCodeBuilder(17, 37)
088      .append(normalizationTargets)
089      .toHashCode();
090  }
091
092  /**
093   * A helper for constructing instances of {@link MergeNormalizationPlan}.
094   */
095  static class Builder {
096
097    private final List<NormalizationTarget> normalizationTargets = new LinkedList<>();
098
099    public Builder setTargets(final List<NormalizationTarget> targets) {
100      normalizationTargets.clear();
101      normalizationTargets.addAll(targets);
102      return this;
103    }
104
105    public Builder addTarget(final RegionInfo regionInfo, final long regionSizeMb) {
106      normalizationTargets.add(new NormalizationTarget(regionInfo, regionSizeMb));
107      return this;
108    }
109
110    public MergeNormalizationPlan build() {
111      return new MergeNormalizationPlan(normalizationTargets);
112    }
113  }
114}