org.apache.hadoop.hbase.client.HRegionLocator Maven / Gradle / Ivy
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*
* 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.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HRegionLocation;
import org.apache.hadoop.hbase.RegionLocations;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import org.apache.hadoop.hbase.util.Pair;
import com.google.common.annotations.VisibleForTesting;
/**
* An implementation of {@link RegionLocator}. Used to view region location information for a single
* HBase table. Lightweight. Get as needed and just close when done. Instances of this class SHOULD
* NOT be constructed directly. Obtain an instance via {@link Connection}. See
* {@link ConnectionFactory} class comment for an example of how.
*
* This class is thread safe
*/
@InterfaceAudience.Private
@InterfaceStability.Stable
public class HRegionLocator implements RegionLocator {
private final TableName tableName;
private final ClusterConnection connection;
public HRegionLocator(TableName tableName, ClusterConnection connection) {
this.connection = connection;
this.tableName = tableName;
}
/**
* {@inheritDoc}
*/
@Override
public void close() throws IOException {
// This method is required by the RegionLocator interface. This implementation does not have any
// persistent state, so there is no need to do anything here.
}
/**
* {@inheritDoc}
*/
@Override
public HRegionLocation getRegionLocation(final byte [] row)
throws IOException {
return connection.getRegionLocation(tableName, row, false);
}
/**
* {@inheritDoc}
*/
@Override
public HRegionLocation getRegionLocation(final byte [] row, boolean reload)
throws IOException {
return connection.getRegionLocation(tableName, row, reload);
}
@Override
public List getAllRegionLocations() throws IOException {
TableName tableName = getName();
ArrayList regions = new ArrayList<>();
for (RegionLocations locations : listRegionLocations()) {
for (HRegionLocation location : locations.getRegionLocations()) {
regions.add(location);
}
connection.cacheLocation(tableName, locations);
}
return regions;
}
/**
* {@inheritDoc}
*/
@Override
public byte[][] getStartKeys() throws IOException {
return getStartEndKeys().getFirst();
}
/**
* {@inheritDoc}
*/
@Override
public byte[][] getEndKeys() throws IOException {
return getStartEndKeys().getSecond();
}
/**
* {@inheritDoc}
*/
@Override
public Pair getStartEndKeys() throws IOException {
return getStartEndKeys(listRegionLocations());
}
@VisibleForTesting
Pair getStartEndKeys(List regions) {
final byte[][] startKeyList = new byte[regions.size()][];
final byte[][] endKeyList = new byte[regions.size()][];
for (int i = 0; i < regions.size(); i++) {
HRegionInfo region = regions.get(i).getRegionLocation().getRegionInfo();
startKeyList[i] = region.getStartKey();
endKeyList[i] = region.getEndKey();
}
return new Pair<>(startKeyList, endKeyList);
}
@Override
public TableName getName() {
return this.tableName;
}
@VisibleForTesting
List listRegionLocations() throws IOException {
return MetaScanner.listTableRegionLocations(getConfiguration(), this.connection, getName());
}
public Configuration getConfiguration() {
return connection.getConfiguration();
}
}