org.apache.sysml.runtime.matrix.data.hadoopfix.DelegatingInputFormat.java Source code

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Here is the source code for org.apache.sysml.runtime.matrix.data.hadoopfix.DelegatingInputFormat.java

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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.sysml.runtime.matrix.data.hadoopfix;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.InputFormat;
import org.apache.hadoop.mapred.InputSplit;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.RecordReader;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.util.ReflectionUtils;
import org.apache.sysml.runtime.matrix.mapred.MRConfigurationNames;

/**
 * An {@link InputFormat} that delegates behaviour of paths to multiple other
 * InputFormats.
 * 
 * @see MultipleInputs#addInputPath(JobConf, Path, Class)
 */
@SuppressWarnings("rawtypes")
public class DelegatingInputFormat<K, V> implements InputFormat<K, V> {

    public InputSplit[] getSplits(JobConf conf, int numSplits) throws IOException {

        JobConf confCopy = new JobConf(conf);
        List<InputSplit> splits = new ArrayList<>();
        Map<Path, InputFormat> formatMap = MultipleInputs.getInputFormatMap(conf);
        Map<Path, Class<? extends Mapper>> mapperMap = MultipleInputs.getMapperTypeMap(conf);
        Map<Class<? extends InputFormat>, List<Path>> formatPaths = new HashMap<>();

        // First, build a map of InputFormats to Paths
        for (Entry<Path, InputFormat> entry : formatMap.entrySet()) {
            if (!formatPaths.containsKey(entry.getValue().getClass())) {
                formatPaths.put(entry.getValue().getClass(), new LinkedList<Path>());
            }

            formatPaths.get(entry.getValue().getClass()).add(entry.getKey());
        }

        for (Entry<Class<? extends InputFormat>, List<Path>> formatEntry : formatPaths.entrySet()) {
            Class<? extends InputFormat> formatClass = formatEntry.getKey();
            InputFormat format = (InputFormat) ReflectionUtils.newInstance(formatClass, conf);
            List<Path> paths = formatEntry.getValue();

            Map<Class<? extends Mapper>, List<Path>> mapperPaths = new HashMap<>();

            // Now, for each set of paths that have a common InputFormat, build
            // a map of Mappers to the paths they're used for
            for (Path path : paths) {
                Class<? extends Mapper> mapperClass = mapperMap.get(path);
                if (!mapperPaths.containsKey(mapperClass)) {
                    mapperPaths.put(mapperClass, new LinkedList<Path>());
                }

                mapperPaths.get(mapperClass).add(path);
            }

            // Now each set of paths that has a common InputFormat and Mapper can
            // be added to the same job, and split together.
            for (Entry<Class<? extends Mapper>, List<Path>> mapEntry : mapperPaths.entrySet()) {
                paths = mapEntry.getValue();
                Class<? extends Mapper> mapperClass = mapEntry.getKey();

                if (mapperClass == null) {
                    mapperClass = conf.getMapperClass();
                }

                FileInputFormat.setInputPaths(confCopy, paths.toArray(new Path[paths.size()]));

                // Get splits for each input path and tag with InputFormat
                // and Mapper types by wrapping in a TaggedInputSplit.
                InputSplit[] pathSplits = format.getSplits(confCopy, numSplits);
                for (InputSplit pathSplit : pathSplits) {
                    splits.add(new TaggedInputSplit(pathSplit, conf, format.getClass(), mapperClass));
                }
            }
        }

        return splits.toArray(new InputSplit[splits.size()]);
    }

    @SuppressWarnings("unchecked")
    public RecordReader<K, V> getRecordReader(InputSplit split, JobConf conf, Reporter reporter)
            throws IOException {

        // Find the InputFormat and then the RecordReader from the
        // TaggedInputSplit.

        TaggedInputSplit taggedInputSplit = (TaggedInputSplit) split;
        InputFormat<K, V> inputFormat = (InputFormat<K, V>) ReflectionUtils
                .newInstance(taggedInputSplit.getInputFormatClass(), conf);
        InputSplit inputSplit = taggedInputSplit.getInputSplit();
        if (inputSplit instanceof FileSplit) {
            FileSplit fileSplit = (FileSplit) inputSplit;
            conf.set(MRConfigurationNames.MR_MAP_INPUT_FILE, fileSplit.getPath().toString());
            conf.setLong(MRConfigurationNames.MR_MAP_INPUT_START, fileSplit.getStart());
            conf.setLong(MRConfigurationNames.MR_MAP_INPUT_LENGTH, fileSplit.getLength());
        }

        return inputFormat.getRecordReader(taggedInputSplit.getInputSplit(), conf, reporter);
    }
}