com.toshiba.mwcloud.gs.hadoop.mapreduce.GSRowInputFormat.java Source code

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Here is the source code for com.toshiba.mwcloud.gs.hadoop.mapreduce.GSRowInputFormat.java

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/*
   Copyright (c) 2016 TOSHIBA CORPORATION.
    
   Licensed 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 com.toshiba.mwcloud.gs.hadoop.mapreduce;

import java.io.IOException;
import java.util.List;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.InputFormat;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;

import com.toshiba.mwcloud.gs.GSException;
import com.toshiba.mwcloud.gs.hadoop.io.GSColumnKeyWritable;
import com.toshiba.mwcloud.gs.hadoop.io.GSRowWritable;
import com.toshiba.mwcloud.gs.hadoop.util.GDInputFormat;

/**
 * <div lang="ja">
 * GridDB?Row??GridDBInputFormat??
 * </div><div lang="en">
 * GridDB InputFormat class using GridDB Row object.
 * </div>
 */
public class GSRowInputFormat extends InputFormat<GSColumnKeyWritable, GSRowWritable> {
    /**
     * <div lang="ja">
     * GridDB?InputSplit???????<br/>
     * InputSplit?????mapreduce.job.maps? ?????????
     * @param context JobContext
     * @throws GSException GridDB??????
     * </div><div lang="en">
     * Generate a list of GridDB InputSplit objects.<br/>
     * The number of InputSplits will be the smaller of the number of partitions for input processing and the value of property mapreduce.job.maps.
     * @param context JobContext object
     * @throws GSException an exception occurred in GridDB
     * </div>
     */
    @Override
    public List<InputSplit> getSplits(JobContext context) throws IOException, InterruptedException {

        Configuration conf = context.getConfiguration();
        int numSplits = conf.getInt("mapreduce.job.maps", 1);
        GDInputFormat inputFormat = new GDInputFormat();
        List<InputSplit> splits = inputFormat.getSplitList(numSplits, conf);
        return splits;
    }

    /*
     * (non Javadoc)
     * @see org.apache.hadoop.mapreduce.InputFormat#createRecordReader(org.apache.hadoop.mapreduce.InputSplit,
     * org.apache.hadoop.mapreduce.TaskAttemptContext)
     */
    @Override
    public RecordReader<GSColumnKeyWritable, GSRowWritable> createRecordReader(InputSplit split,
            TaskAttemptContext context) throws IOException, InterruptedException {
        RecordReader<GSColumnKeyWritable, GSRowWritable> reader = new GSRowRecordReader();
        reader.initialize(split, context);
        return reader;
    }
}