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.master.normalizer;
019
020import java.util.Collections;
021import java.util.LinkedList;
022import java.util.List;
023import org.apache.commons.lang3.builder.EqualsBuilder;
024import org.apache.commons.lang3.builder.HashCodeBuilder;
025import org.apache.commons.lang3.builder.ToStringBuilder;
026import org.apache.commons.lang3.builder.ToStringStyle;
027import org.apache.hadoop.hbase.client.RegionInfo;
028import org.apache.hadoop.hbase.master.MasterServices;
029import org.apache.yetus.audience.InterfaceAudience;
030
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)} with
036 * {@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 {code mergeRegions}
038 * 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).toString();
065  }
066
067  @Override
068  public boolean equals(Object o) {
069    if (this == o) {
070      return true;
071    }
072
073    if (o == null || getClass() != o.getClass()) {
074      return false;
075    }
076
077    MergeNormalizationPlan that = (MergeNormalizationPlan) o;
078
079    return new EqualsBuilder().append(normalizationTargets, that.normalizationTargets).isEquals();
080  }
081
082  @Override
083  public int hashCode() {
084    return new HashCodeBuilder(17, 37).append(normalizationTargets).toHashCode();
085  }
086
087  /**
088   * A helper for constructing instances of {@link MergeNormalizationPlan}.
089   */
090  static class Builder {
091
092    private final List<NormalizationTarget> normalizationTargets = new LinkedList<>();
093
094    public Builder setTargets(final List<NormalizationTarget> targets) {
095      normalizationTargets.clear();
096      normalizationTargets.addAll(targets);
097      return this;
098    }
099
100    public Builder addTarget(final RegionInfo regionInfo, final long regionSizeMb) {
101      normalizationTargets.add(new NormalizationTarget(regionInfo, regionSizeMb));
102      return this;
103    }
104
105    public MergeNormalizationPlan build() {
106      return new MergeNormalizationPlan(normalizationTargets);
107    }
108  }
109}