1 /** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, software 14 * distributed under the License is distributed on an "AS IS" BASIS, 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16 * See the License for the specific language governing permissions and 17 * limitations under the License. 18 */ 19 package org.apache.hadoop.hbase.regionserver; 20 21 import java.net.InetSocketAddress; 22 import java.util.List; 23 24 import org.apache.hadoop.hbase.HBaseInterfaceAudience; 25 import org.apache.hadoop.hbase.classification.InterfaceAudience; 26 import org.apache.hadoop.hbase.classification.InterfaceStability; 27 import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.ServerName; 28 29 /** 30 * Abstraction that allows different modules in RegionServer to update/get 31 * the favored nodes information for regions. 32 */ 33 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.COPROC) 34 @InterfaceStability.Evolving 35 public interface FavoredNodesForRegion { 36 /** 37 * Used to update the favored nodes mapping when required. 38 * @param encodedRegionName 39 * @param favoredNodes 40 */ 41 void updateRegionFavoredNodesMapping(String encodedRegionName, List<ServerName> favoredNodes); 42 43 /** 44 * Get the favored nodes mapping for this region. Used when the HDFS create API 45 * is invoked to pass in favored nodes hints for new region files. 46 * @param encodedRegionName 47 * @return array containing the favored nodes' InetSocketAddresses 48 */ 49 InetSocketAddress[] getFavoredNodesForRegion(String encodedRegionName); 50 }