com.ibm.bi.dml.runtime.transform.GTFMTDMapper.java Source code

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Here is the source code for com.ibm.bi.dml.runtime.transform.GTFMTDMapper.java

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/**
 * (C) Copyright IBM Corp. 2010, 2015
 *
 * 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.ibm.bi.dml.runtime.transform;

import java.io.IOException;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.apache.wink.json4j.JSONException;

import com.ibm.bi.dml.runtime.matrix.CSVReblockMR.OffsetCount;

public class GTFMTDMapper implements Mapper<LongWritable, Text, IntWritable, DistinctValue> {

    private OutputCollector<IntWritable, DistinctValue> _collector = null;
    private int _mapTaskID = -1;

    TfUtils _agents = null;

    private boolean _partFileWithHeader = false;
    private boolean _firstRecordInSplit = true;
    private String _partFileName = null;
    private long _offsetInPartFile = -1;

    // ----------------------------------------------------------------------------------------------

    /**
     * Configure the information used in the mapper, and setup transformation agents.
     */
    @Override
    public void configure(JobConf job) {
        String[] parts = job.get("mapred.task.id").split("_");
        if (parts[0].equalsIgnoreCase("task")) {
            _mapTaskID = Integer.parseInt(parts[parts.length - 1]);
        } else if (parts[0].equalsIgnoreCase("attempt")) {
            _mapTaskID = Integer.parseInt(parts[parts.length - 2]);
        } else {
            throw new RuntimeException("Unrecognized format for taskID: " + job.get("mapred.task.id"));
        }

        try {
            _partFileName = TfUtils.getPartFileName(job);
            _partFileWithHeader = TfUtils.isPartFileWithHeader(job);
            _agents = new TfUtils(job);
        } catch (IOException e) {
            throw new RuntimeException(e);
        } catch (JSONException e) {
            throw new RuntimeException(e);
        }

    }

    public void map(LongWritable rawKey, Text rawValue, OutputCollector<IntWritable, DistinctValue> out,
            Reporter reporter) throws IOException {

        if (_firstRecordInSplit) {
            _firstRecordInSplit = false;
            _collector = out;
            _offsetInPartFile = rawKey.get();
        }

        // ignore header
        if (_agents.hasHeader() && rawKey.get() == 0 && _partFileWithHeader)
            return;

        _agents.prepareTfMtd(rawValue.toString());
    }

    @Override
    public void close() throws IOException {
        _agents.getMVImputeAgent().mapOutputTransformationMetadata(_collector, _mapTaskID, _agents);
        _agents.getRecodeAgent().mapOutputTransformationMetadata(_collector, _mapTaskID, _agents);
        _agents.getBinAgent().mapOutputTransformationMetadata(_collector, _mapTaskID, _agents);

        // Output part-file offsets to create OFFSETS_FILE, which is to be used in csv reblocking.
        // OffsetCount is denoted as a DistinctValue by concatenating parfile name and offset within partfile.
        _collector.collect(new IntWritable((int) _agents.getNumCols() + 1),
                new DistinctValue(new OffsetCount(_partFileName, _offsetInPartFile, _agents.getValid())));

        // reset global variables, required when the jvm is reused.
        _firstRecordInSplit = true;
        _offsetInPartFile = -1;
        _partFileWithHeader = false;
    }

}