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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 org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
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.mapreduce.TableSnapshotInputFormatImpl;
import org.apache.hadoop.hbase.util.RegionSplitter;
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.hadoop.mapreduce.Job;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.List;
/**
* TableSnapshotInputFormat allows a MapReduce job to run over a table snapshot. Further
* documentation available on {@link org.apache.hadoop.hbase.mapreduce.TableSnapshotInputFormat}.
*
* @see org.apache.hadoop.hbase.mapreduce.TableSnapshotInputFormat
*/
@InterfaceAudience.Public
@InterfaceStability.Evolving
public class TableSnapshotInputFormat implements InputFormat {
public static class TableSnapshotRegionSplit implements InputSplit {
private TableSnapshotInputFormatImpl.InputSplit delegate;
// constructor for mapreduce framework / Writable
public TableSnapshotRegionSplit() {
this.delegate = new TableSnapshotInputFormatImpl.InputSplit();
}
public TableSnapshotRegionSplit(TableSnapshotInputFormatImpl.InputSplit delegate) {
this.delegate = delegate;
}
public TableSnapshotRegionSplit(HTableDescriptor htd, HRegionInfo regionInfo,
List locations, Scan scan, Path restoreDir) {
this.delegate =
new TableSnapshotInputFormatImpl.InputSplit(htd, regionInfo, locations, scan, restoreDir);
}
@Override
public long getLength() throws IOException {
return delegate.getLength();
}
@Override
public String[] getLocations() throws IOException {
return delegate.getLocations();
}
@Override
public void write(DataOutput out) throws IOException {
delegate.write(out);
}
@Override
public void readFields(DataInput in) throws IOException {
delegate.readFields(in);
}
}
static class TableSnapshotRecordReader
implements RecordReader {
private TableSnapshotInputFormatImpl.RecordReader delegate;
public TableSnapshotRecordReader(TableSnapshotRegionSplit split, JobConf job)
throws IOException {
delegate = new TableSnapshotInputFormatImpl.RecordReader();
delegate.initialize(split.delegate, job);
}
@Override
public boolean next(ImmutableBytesWritable key, Result value) throws IOException {
if (!delegate.nextKeyValue()) {
return false;
}
ImmutableBytesWritable currentKey = delegate.getCurrentKey();
key.set(currentKey.get(), currentKey.getOffset(), currentKey.getLength());
value.copyFrom(delegate.getCurrentValue());
return true;
}
@Override
public ImmutableBytesWritable createKey() {
return new ImmutableBytesWritable();
}
@Override
public Result createValue() {
return new Result();
}
@Override
public long getPos() throws IOException {
return delegate.getPos();
}
@Override
public void close() throws IOException {
delegate.close();
}
@Override
public float getProgress() throws IOException {
return delegate.getProgress();
}
}
@Override
public InputSplit[] getSplits(JobConf job, int numSplits) throws IOException {
List splits =
TableSnapshotInputFormatImpl.getSplits(job);
InputSplit[] results = new InputSplit[splits.size()];
for (int i = 0; i < splits.size(); i++) {
results[i] = new TableSnapshotRegionSplit(splits.get(i));
}
return results;
}
@Override
public RecordReader
getRecordReader(InputSplit split, JobConf job, Reporter reporter) throws IOException {
return new TableSnapshotRecordReader((TableSnapshotRegionSplit) split, job);
}
/**
* Configures the job to use TableSnapshotInputFormat to read from a snapshot.
* @param job the job to configure
* @param snapshotName the name of the snapshot to read from
* @param restoreDir a temporary directory to restore the snapshot into. Current user should
* have write permissions to this directory, and this should not be a subdirectory of rootdir.
* After the job is finished, restoreDir can be deleted.
* @throws IOException if an error occurs
*/
public static void setInput(JobConf job, String snapshotName, Path restoreDir)
throws IOException {
TableSnapshotInputFormatImpl.setInput(job, snapshotName, restoreDir);
}
/**
* Configures the job to use TableSnapshotInputFormat to read from a snapshot.
* @param job the job to configure
* @param snapshotName the name of the snapshot to read from
* @param restoreDir a temporary directory to restore the snapshot into. Current user should
* have write permissions to this directory, and this should not be a subdirectory of rootdir.
* After the job is finished, restoreDir can be deleted.
* @param splitAlgo split algorithm to generate splits from region
* @param numSplitsPerRegion how many input splits to generate per one region
* @throws IOException if an error occurs
*/
public static void setInput(JobConf job, String snapshotName, Path restoreDir,
RegionSplitter.SplitAlgorithm splitAlgo, int numSplitsPerRegion) throws IOException {
TableSnapshotInputFormatImpl.setInput(job, snapshotName, restoreDir, splitAlgo, numSplitsPerRegion);
}
}
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