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

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Here is the source code for org.apache.avro.mapred.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.avro.mapred;

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

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.Reporter;

import org.apache.avro.Schema;
import org.apache.avro.util.Utf8;
import org.junit.Test;

public class TestWordCount {

    public static class MapImpl extends AvroMapper<Utf8, Pair<Utf8, Long>> {
        @Override
        public void map(Utf8 text, AvroCollector<Pair<Utf8, Long>> collector, Reporter reporter)
                throws IOException {
            StringTokenizer tokens = new StringTokenizer(text.toString());
            while (tokens.hasMoreTokens())
                collector.collect(new Pair<Utf8, Long>(new Utf8(tokens.nextToken()), 1L));
        }
    }

    public static class ReduceImpl extends AvroReducer<Utf8, Long, Pair<Utf8, Long>> {
        @Override
        public void reduce(Utf8 word, Iterable<Long> counts, AvroCollector<Pair<Utf8, Long>> collector,
                Reporter reporter) throws IOException {
            long sum = 0;
            for (long count : counts)
                sum += count;
            collector.collect(new Pair<Utf8, Long>(word, sum));
        }
    }

    @Test
    public void runTestsInOrder() throws Exception {
        testJob();
        testProjection();
    }

    @SuppressWarnings("deprecation")
    public void testJob() throws Exception {
        JobConf job = new JobConf();
        String dir = System.getProperty("test.dir", ".") + "/mapred";
        Path outputPath = new Path(dir + "/out");

        outputPath.getFileSystem(job).delete(outputPath);
        WordCountUtil.writeLinesFile();

        job.setJobName("wordcount");

        AvroJob.setInputSchema(job, Schema.create(Schema.Type.STRING));
        AvroJob.setOutputSchema(job, new Pair<Utf8, Long>(new Utf8(""), 0L).getSchema());

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

        FileInputFormat.setInputPaths(job, new Path(dir + "/in"));
        FileOutputFormat.setOutputPath(job, outputPath);
        FileOutputFormat.setCompressOutput(job, true);

        WordCountUtil.setMeta(job);

        JobClient.runJob(job);

        WordCountUtil.validateCountsFile();
    }

    @SuppressWarnings("deprecation")
    public void testProjection() throws Exception {
        JobConf job = new JobConf();

        Integer defaultRank = new Integer(-1);

        String jsonSchema = "{\"type\":\"record\"," + "\"name\":\"org.apache.avro.mapred.Pair\"," + "\"fields\": [ "
                + "{\"name\":\"rank\", \"type\":\"int\", \"default\": -1},"
                + "{\"name\":\"value\", \"type\":\"long\"}" + "]}";

        Schema readerSchema = Schema.parse(jsonSchema);

        AvroJob.setInputSchema(job, readerSchema);

        String dir = System.getProperty("test.dir", ".") + "/mapred";
        Path inputPath = new Path(dir + "/out" + "/part-00000" + AvroOutputFormat.EXT);
        FileStatus fileStatus = FileSystem.get(job).getFileStatus(inputPath);
        FileSplit fileSplit = new FileSplit(inputPath, 0, fileStatus.getLen(), job);

        AvroRecordReader<Pair<Integer, Long>> recordReader = new AvroRecordReader<Pair<Integer, Long>>(job,
                fileSplit);

        AvroWrapper<Pair<Integer, Long>> inputPair = new AvroWrapper<Pair<Integer, Long>>(null);
        NullWritable ignore = NullWritable.get();

        long sumOfCounts = 0;
        long numOfCounts = 0;
        while (recordReader.next(inputPair, ignore)) {
            Assert.assertEquals((Integer) inputPair.datum().get(0), defaultRank);
            sumOfCounts += (Long) inputPair.datum().get(1);
            numOfCounts++;
        }

        Assert.assertEquals(numOfCounts, WordCountUtil.COUNTS.size());

        long actualSumOfCounts = 0;
        for (Long count : WordCountUtil.COUNTS.values()) {
            actualSumOfCounts += count;
        }

        Assert.assertEquals(sumOfCounts, actualSumOfCounts);
    }

}