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.regionserver;
020
021import java.net.InetSocketAddress;
022import java.util.List;
023
024import org.apache.hadoop.hbase.shaded.protobuf.generated.HBaseProtos.ServerName;
025import org.apache.yetus.audience.InterfaceAudience;
026
027/**
028 * Abstraction that allows different modules in RegionServer to update/get
029 * the favored nodes information for regions. 
030 */
031@InterfaceAudience.Private
032public interface FavoredNodesForRegion {
033  /**
034   * Used to update the favored nodes mapping when required.
035   * @param encodedRegionName
036   * @param favoredNodes
037   */
038  void updateRegionFavoredNodesMapping(String encodedRegionName, List<ServerName> favoredNodes);
039
040  /**
041   * Get the favored nodes mapping for this region. Used when the HDFS create API
042   * is invoked to pass in favored nodes hints for new region files.
043   * @param encodedRegionName
044   * @return array containing the favored nodes' InetSocketAddresses
045   */
046  InetSocketAddress[] getFavoredNodesForRegion(String encodedRegionName);
047}