/**
* 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.hcatalog.hbase;
import java.io.IOException;
import java.util.List;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.hbase.mapred.TableSplit;
import org.apache.hadoop.hbase.mapreduce.TableInputFormat;
import org.apache.hadoop.mapred.HCatMapRedUtil;
import org.apache.hadoop.mapred.InputFormat;
import org.apache.hadoop.mapred.InputSplit;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.RecordReader;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hcatalog.common.HCatConstants;
import org.apache.hcatalog.common.HCatUtil;
import org.apache.hcatalog.mapreduce.InputJobInfo;
/**
* This class HBaseInputFormat is a wrapper class of TableInputFormat in HBase.
*/
class HBaseInputFormat implements InputFormat<ImmutableBytesWritable, Result> {
private final TableInputFormat inputFormat;
public HBaseInputFormat() {
inputFormat = new TableInputFormat();
}
/*
* @param instance of InputSplit
*
* @param instance of TaskAttemptContext
*
* @return RecordReader
*
* @throws IOException
*
* @throws InterruptedException
*
* @see
* org.apache.hadoop.mapreduce.InputFormat#createRecordReader(org.apache
* .hadoop.mapreduce.InputSplit,
* org.apache.hadoop.mapreduce.TaskAttemptContext)
*/
@Override
public RecordReader<ImmutableBytesWritable, Result> getRecordReader(
InputSplit split, JobConf job, Reporter reporter)
throws IOException {
String jobString = job.get(HCatConstants.HCAT_KEY_JOB_INFO);
InputJobInfo inputJobInfo = (InputJobInfo) HCatUtil.deserialize(jobString);
String tableName = job.get(TableInputFormat.INPUT_TABLE);
TableSplit tSplit = (TableSplit) split;
HbaseSnapshotRecordReader recordReader = new HbaseSnapshotRecordReader(inputJobInfo, job);
inputFormat.setConf(job);
Scan inputScan = inputFormat.getScan();
// TODO: Make the caching configurable by the user
inputScan.setCaching(200);
inputScan.setCacheBlocks(false);
Scan sc = new Scan(inputScan);
sc.setStartRow(tSplit.getStartRow());
sc.setStopRow(tSplit.getEndRow());
recordReader.setScan(sc);
recordReader.setHTable(new HTable(job, tableName));
recordReader.init();
return recordReader;
}
/*
* @param jobContext
*
* @return List of InputSplit
*
* @throws IOException
*
* @throws InterruptedException
*
* @see
* org.apache.hadoop.mapreduce.InputFormat#getSplits(org.apache.hadoop.mapreduce
* .JobContext)
*/
@Override
public org.apache.hadoop.mapred.InputSplit[] getSplits(JobConf job, int numSplits)
throws IOException {
inputFormat.setConf(job);
return convertSplits(inputFormat.getSplits(HCatMapRedUtil.createJobContext(job, null,
Reporter.NULL)));
}
private InputSplit[] convertSplits(List<org.apache.hadoop.mapreduce.InputSplit> splits) {
InputSplit[] converted = new InputSplit[splits.size()];
for (int i = 0; i < splits.size(); i++) {
org.apache.hadoop.hbase.mapreduce.TableSplit tableSplit =
(org.apache.hadoop.hbase.mapreduce.TableSplit) splits.get(i);
TableSplit newTableSplit = new TableSplit(tableSplit.getTableName(),
tableSplit.getStartRow(),
tableSplit.getEndRow(), tableSplit.getRegionLocation());
converted[i] = newTableSplit;
}
return converted;
}
}