/** * * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.hadoop.hbase.client; import java.io.Closeable; import java.io.IOException; import java.util.List; import java.util.stream.Collectors; import org.apache.hadoop.hbase.HRegionLocation; import org.apache.hadoop.hbase.TableName; import org.apache.yetus.audience.InterfaceAudience; import org.apache.hadoop.hbase.util.Pair; /** * Used to view region location information for a single HBase table. Obtain an instance from an * {@link Connection}. * @see ConnectionFactory * @see Connection * @see Table * @since 0.99.0 */ @InterfaceAudience.Public public interface RegionLocator extends Closeable { /** * Finds the region on which the given row is being served. Does not reload the cache. * @param row Row to find. * @return Location of the row. * @throws IOException if a remote or network exception occurs */ default HRegionLocation getRegionLocation(byte[] row) throws IOException { return getRegionLocation(row, false); } /** * Finds the region on which the given row is being served. * @param row Row to find. * @param reload true to reload information or false to use cached information * @return Location of the row. * @throws IOException if a remote or network exception occurs */ default HRegionLocation getRegionLocation(byte[] row, boolean reload) throws IOException { return getRegionLocation(row, RegionInfo.DEFAULT_REPLICA_ID, reload); } /** * Finds the region with the given replica id on which the given row is being served. * @param row Row to find. * @param replicaId the replica id * @return Location of the row. * @throws IOException if a remote or network exception occurs */ default HRegionLocation getRegionLocation(byte[] row, int replicaId) throws IOException { return getRegionLocation(row, replicaId, false); } /** * Finds the region with the given replica id on which the given row is being served. * @param row Row to find. * @param replicaId the replica id * @param reload true to reload information or false to use cached information * @return Location of the row. * @throws IOException if a remote or network exception occurs */ HRegionLocation getRegionLocation(byte[] row, int replicaId, boolean reload) throws IOException; /** * Find all the replicas for the region on which the given row is being served. * @param row Row to find. * @return Locations for all the replicas of the row. * @throws IOException if a remote or network exception occurs */ default List<HRegionLocation> getRegionLocations(byte[] row) throws IOException { return getRegionLocations(row, false); } /** * Find all the replicas for the region on which the given row is being served. * @param row Row to find. * @param reload true to reload information or false to use cached information * @return Locations for all the replicas of the row. * @throws IOException if a remote or network exception occurs */ List<HRegionLocation> getRegionLocations(byte[] row, boolean reload) throws IOException; /** * Clear all the entries in the region location cache. * <p/> * This may cause performance issue so use it with caution. */ void clearRegionLocationCache(); /** * Retrieves all of the regions associated with this table. * <p/> * Usually we will go to meta table directly in this method so there is no {@code reload} * parameter. * <p/> * Notice that the location for region replicas other than the default replica are also returned. * @return a {@link List} of all regions associated with this table. * @throws IOException if a remote or network exception occurs */ List<HRegionLocation> getAllRegionLocations() throws IOException; /** * Gets the starting row key for every region in the currently open table. * <p> * This is mainly useful for the MapReduce integration. * @return Array of region starting row keys * @throws IOException if a remote or network exception occurs */ default byte[][] getStartKeys() throws IOException { return getStartEndKeys().getFirst(); } /** * Gets the ending row key for every region in the currently open table. * <p> * This is mainly useful for the MapReduce integration. * @return Array of region ending row keys * @throws IOException if a remote or network exception occurs */ default byte[][] getEndKeys() throws IOException { return getStartEndKeys().getSecond(); } /** * Gets the starting and ending row keys for every region in the currently open table. * <p> * This is mainly useful for the MapReduce integration. * @return Pair of arrays of region starting and ending row keys * @throws IOException if a remote or network exception occurs */ default Pair<byte[][], byte[][]> getStartEndKeys() throws IOException { List<HRegionLocation> regions = getAllRegionLocations().stream() .filter(loc -> RegionReplicaUtil.isDefaultReplica(loc.getRegion())) .collect(Collectors.toList()); byte[][] startKeys = new byte[regions.size()][]; byte[][] endKeys = new byte[regions.size()][]; for (int i = 0, n = regions.size(); i < n; i++) { RegionInfo region = regions.get(i).getRegion(); startKeys[i] = region.getStartKey(); endKeys[i] = region.getEndKey(); } return Pair.newPair(startKeys, endKeys); } /** * Gets the fully qualified table name instance of this table. */ TableName getName(); }