org.apache.trevni.avro.TestWordCount.java Source code

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Here is the source code for org.apache.trevni.avro.TestWordCount.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.trevni.avro;

import java.io.IOException;
import java.util.StringTokenizer;
import java.io.File;

import junit.framework.Assert;

import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapred.FileSplit;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.lib.NullOutputFormat;
import org.apache.hadoop.mapred.Reporter;

import org.apache.avro.Schema;
import org.apache.avro.generic.GenericData;
import org.apache.avro.generic.GenericRecord;
import org.apache.avro.mapred.AvroJob;
import org.apache.avro.mapred.Pair;
import org.apache.avro.mapred.AvroMapper;
import org.apache.avro.mapred.AvroReducer;
import org.apache.avro.mapred.AvroCollector;

import org.apache.avro.Schema;

import org.junit.Test;
import static org.junit.Assert.*;

public class TestWordCount {

    public static class MapImpl extends AvroMapper<String, Pair<String, Long>> {
        @Override
        public void map(String text, AvroCollector<Pair<String, Long>> collector, Reporter reporter)
                throws IOException {
            StringTokenizer tokens = new StringTokenizer(text.toString());
            while (tokens.hasMoreTokens())
                collector.collect(new Pair<String, Long>(tokens.nextToken(), 1L));
        }
    }

    public static class ReduceImpl extends AvroReducer<String, Long, Pair<String, Long>> {
        @Override
        public void reduce(String word, Iterable<Long> counts, AvroCollector<Pair<String, Long>> collector,
                Reporter reporter) throws IOException {
            long sum = 0;
            for (long count : counts)
                sum += count;
            collector.collect(new Pair<String, Long>(word, sum));
        }
    }

    @Test
    public void runTestsInOrder() throws Exception {
        testOutputFormat();
        testInputFormat();
    }

    static final Schema STRING = Schema.create(Schema.Type.STRING);
    static {
        GenericData.setStringType(STRING, GenericData.StringType.String);
    }
    static final Schema LONG = Schema.create(Schema.Type.LONG);

    public void testOutputFormat() throws Exception {
        JobConf job = new JobConf();

        WordCountUtil wordCountUtil = new WordCountUtil("trevniMapredTest");

        wordCountUtil.writeLinesFile();

        AvroJob.setInputSchema(job, STRING);
        AvroJob.setOutputSchema(job, Pair.getPairSchema(STRING, LONG));

        AvroJob.setMapperClass(job, MapImpl.class);
        AvroJob.setCombinerClass(job, ReduceImpl.class);
        AvroJob.setReducerClass(job, ReduceImpl.class);

        FileInputFormat.setInputPaths(job, new Path(wordCountUtil.getDir().toString() + "/in"));
        FileOutputFormat.setOutputPath(job, new Path(wordCountUtil.getDir().toString() + "/out"));
        FileOutputFormat.setCompressOutput(job, true);

        job.setOutputFormat(AvroTrevniOutputFormat.class);

        JobClient.runJob(job);

        wordCountUtil.validateCountsFile();
    }

    private static long total;

    public static class Counter extends AvroMapper<GenericRecord, Void> {
        @Override
        public void map(GenericRecord r, AvroCollector<Void> collector, Reporter reporter) throws IOException {
            total += (Long) r.get("value");
        }
    }

    public void testInputFormat() throws Exception {
        JobConf job = new JobConf();

        WordCountUtil wordCountUtil = new WordCountUtil("trevniMapredTest");

        Schema subSchema = Schema.parse("{\"type\":\"record\"," + "\"name\":\"PairValue\"," + "\"fields\": [ "
                + "{\"name\":\"value\", \"type\":\"long\"}" + "]}");
        AvroJob.setInputSchema(job, subSchema);
        AvroJob.setMapperClass(job, Counter.class);
        FileInputFormat.setInputPaths(job, new Path(wordCountUtil.getDir().toString() + "/out/*"));
        job.setInputFormat(AvroTrevniInputFormat.class);

        job.setNumReduceTasks(0); // map-only
        job.setOutputFormat(NullOutputFormat.class); // ignore output

        total = 0;
        JobClient.runJob(job);
        assertEquals(WordCountUtil.TOTAL, total);
    }

}