Example usage for org.apache.hadoop.mapred.lib ChainReducer setReducer

Introduction

In this page you can find the example usage for org.apache.hadoop.mapred.lib ChainReducer setReducer.

Prototype

public static <K1, V1, K2, V2> void setReducer(JobConf job, Class<? extends Reducer<K1, V1, K2, V2>> klass,
        Class<? extends K1> inputKeyClass, Class<? extends V1> inputValueClass,
        Class<? extends K2> outputKeyClass, Class<? extends V2> outputValueClass, boolean byValue,
        JobConf reducerConf) 

Source Link

Document

Sets the Reducer class to the chain job's JobConf.

Usage

From source file:name.abhijitsarkar.hadoop.citation.CitationCombinerWithChaining.java

License:Open Source License

@Override
public int run(String[] args) throws Exception {
    JobConf conf = new JobConf(getConf(), getClass());
    conf.setJobName("citation-combiner-with-chaining");

    conf.setInputFormat(TextInputFormat.class);
    conf.setOutputFormat(TextOutputFormat.class);

    FileInputFormat.setInputPaths(conf, new Path(args[0]));
    FileOutputFormat.setOutputPath(conf, new Path(args[1]));

    JobConf map1Conf = new JobConf(false);

    ChainMapper.addMapper(conf, CitationInputSplitMapper.class, LongWritable.class, Text.class, Text.class,
            Text.class, true, map1Conf);

    JobConf map2Conf = new JobConf(false);

    ChainMapper.addMapper(conf, CitationHeaderStripMapper.class, Text.class, Text.class, Text.class, Text.class,
            true, map2Conf);/* w ww.  j av a2  s .co  m*/

    JobConf red1Conf = new JobConf(false);

    ChainReducer.setReducer(conf, CitationReducer.class, Text.class, Text.class, Text.class, Text.class, true,
            red1Conf);

    JobClient.runJob(conf);

    return 0;
}

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