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.balancer;
019
020import java.util.List;
021import org.apache.hadoop.hbase.master.RegionPlan;
022import org.apache.yetus.audience.InterfaceAudience;
023
024import org.apache.hbase.thirdparty.com.google.common.collect.ImmutableList;
025
026@InterfaceAudience.Private
027public class SwapRegionsAction extends BalanceAction {
028  private final int fromServer;
029  private final int fromRegion;
030  private final int toServer;
031  private final int toRegion;
032
033  SwapRegionsAction(int fromServer, int fromRegion, int toServer, int toRegion) {
034    super(Type.SWAP_REGIONS);
035    this.fromServer = fromServer;
036    this.fromRegion = fromRegion;
037    this.toServer = toServer;
038    this.toRegion = toRegion;
039  }
040
041  public int getFromServer() {
042    return fromServer;
043  }
044
045  public int getFromRegion() {
046    return fromRegion;
047  }
048
049  public int getToServer() {
050    return toServer;
051  }
052
053  public int getToRegion() {
054    return toRegion;
055  }
056
057  @Override
058  public BalanceAction undoAction() {
059    return new SwapRegionsAction(fromServer, toRegion, toServer, fromRegion);
060  }
061
062  @Override
063  List<RegionPlan> toRegionPlans(BalancerClusterState cluster) {
064    return ImmutableList.of(
065      new RegionPlan(cluster.regions[getFromRegion()], cluster.servers[getFromServer()],
066        cluster.servers[getToServer()]),
067      new RegionPlan(cluster.regions[getToRegion()], cluster.servers[getToServer()],
068        cluster.servers[getFromServer()]));
069  }
070
071  @Override
072  public String toString() {
073    return getType() + ": " + fromRegion + ":" + fromServer + " <-> " + toRegion + ":" + toServer;
074  }
075}