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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.mapred;
import java.io.IOException;
import org.apache.hadoop.fs.FileAlreadyExistsException;
import org.apache.hadoop.fs.FileSystem;
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.client.BufferedMutator;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.InvalidJobConfException;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.RecordWriter;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.util.Progressable;
/**
* Convert Map/Reduce output and write it to an HBase table
*/
@InterfaceAudience.Public
@InterfaceStability.Stable
public class TableOutputFormat extends FileOutputFormat {
/** JobConf parameter that specifies the output table */
public static final String OUTPUT_TABLE = "hbase.mapred.outputtable";
/**
* Convert Reduce output (key, value) to (HStoreKey, KeyedDataArrayWritable)
* and write to an HBase table.
*/
protected static class TableRecordWriter implements RecordWriter {
private BufferedMutator m_mutator;
private Connection connection;
/**
* Instantiate a TableRecordWriter with the HBase HClient for writing. Assumes control over the
* lifecycle of {@code conn}.
*/
public TableRecordWriter(final BufferedMutator mutator) throws IOException {
this.m_mutator = mutator;
}
public TableRecordWriter(JobConf job) throws IOException {
// expecting exactly one path
TableName tableName = TableName.valueOf(job.get(OUTPUT_TABLE));
connection = ConnectionFactory.createConnection(job);
m_mutator = connection.getBufferedMutator(tableName);
}
public void close(Reporter reporter) throws IOException {
try {
if (this.m_mutator != null) {
this.m_mutator.close();
}
} finally {
if (connection != null) {
connection.close();
connection = null;
}
}
}
public void write(ImmutableBytesWritable key, Put value) throws IOException {
m_mutator.mutate(new Put(value));
}
}
@Override
public RecordWriter getRecordWriter(FileSystem ignored, JobConf job, String name,
Progressable progress)
throws IOException {
return new TableRecordWriter(job);
}
@Override
public void checkOutputSpecs(FileSystem ignored, JobConf job)
throws FileAlreadyExistsException, InvalidJobConfException, IOException {
String tableName = job.get(OUTPUT_TABLE);
if (tableName == null) {
throw new IOException("Must specify table name");
}
}
}
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