org.apache.hadoop.mapred.TestMultiFileInputFormat.java Source code

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Here is the source code for org.apache.hadoop.mapred.TestMultiFileInputFormat.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.hadoop.mapred;

import java.io.IOException;
import java.util.BitSet;
import java.util.HashMap;
import java.util.Random;

import junit.framework.TestCase;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;

public class TestMultiFileInputFormat extends TestCase {

    private static JobConf job = new JobConf();

    private static final Log LOG = LogFactory.getLog(TestMultiFileInputFormat.class);

    private static final int MAX_SPLIT_COUNT = 10000;
    private static final int SPLIT_COUNT_INCR = 6000;
    private static final int MAX_BYTES = 1024;
    private static final int MAX_NUM_FILES = 10000;
    private static final int NUM_FILES_INCR = 8000;

    private Random rand = new Random(System.currentTimeMillis());
    private HashMap<String, Long> lengths = new HashMap<String, Long>();

    /** Dummy class to extend MultiFileInputFormat*/
    private class DummyMultiFileInputFormat extends MultiFileInputFormat<Text, Text> {
        @Override
        public RecordReader<Text, Text> getRecordReader(InputSplit split, JobConf job, Reporter reporter)
                throws IOException {
            return null;
        }
    }

    private Path initFiles(FileSystem fs, int numFiles, int numBytes) throws IOException {
        Path dir = new Path(System.getProperty("test.build.data", ".") + "/mapred");
        Path multiFileDir = new Path(dir, "test.multifile");
        fs.delete(multiFileDir, true);
        fs.mkdirs(multiFileDir);
        LOG.info("Creating " + numFiles + " file(s) in " + multiFileDir);
        for (int i = 0; i < numFiles; i++) {
            Path path = new Path(multiFileDir, "file_" + i);
            FSDataOutputStream out = fs.create(path);
            if (numBytes == -1) {
                numBytes = rand.nextInt(MAX_BYTES);
            }
            for (int j = 0; j < numBytes; j++) {
                out.write(rand.nextInt());
            }
            out.close();
            if (LOG.isDebugEnabled()) {
                LOG.debug("Created file " + path + " with length " + numBytes);
            }
            lengths.put(path.getName(), new Long(numBytes));
        }
        FileInputFormat.setInputPaths(job, multiFileDir);
        return multiFileDir;
    }

    public void testFormat() throws IOException {
        if (LOG.isInfoEnabled()) {
            LOG.info("Test started");
            LOG.info("Max split count           = " + MAX_SPLIT_COUNT);
            LOG.info("Split count increment     = " + SPLIT_COUNT_INCR);
            LOG.info("Max bytes per file        = " + MAX_BYTES);
            LOG.info("Max number of files       = " + MAX_NUM_FILES);
            LOG.info("Number of files increment = " + NUM_FILES_INCR);
        }

        MultiFileInputFormat<Text, Text> format = new DummyMultiFileInputFormat();
        FileSystem fs = FileSystem.getLocal(job);

        for (int numFiles = 1; numFiles < MAX_NUM_FILES; numFiles += (NUM_FILES_INCR / 2)
                + rand.nextInt(NUM_FILES_INCR / 2)) {

            Path dir = initFiles(fs, numFiles, -1);
            BitSet bits = new BitSet(numFiles);
            for (int i = 1; i < MAX_SPLIT_COUNT; i += rand.nextInt(SPLIT_COUNT_INCR) + 1) {
                LOG.info("Running for Num Files=" + numFiles + ", split count=" + i);

                MultiFileSplit[] splits = (MultiFileSplit[]) format.getSplits(job, i);
                bits.clear();

                for (MultiFileSplit split : splits) {
                    long splitLength = 0;
                    for (Path p : split.getPaths()) {
                        long length = fs.getContentSummary(p).getLength();
                        assertEquals(length, lengths.get(p.getName()).longValue());
                        splitLength += length;
                        String name = p.getName();
                        int index = Integer.parseInt(name.substring(name.lastIndexOf("file_") + 5));
                        assertFalse(bits.get(index));
                        bits.set(index);
                    }
                    assertEquals(splitLength, split.getLength());
                }
            }
            assertEquals(bits.cardinality(), numFiles);
            fs.delete(dir, true);
        }
        LOG.info("Test Finished");
    }

    public void testFormatWithLessPathsThanSplits() throws Exception {
        MultiFileInputFormat<Text, Text> format = new DummyMultiFileInputFormat();
        FileSystem fs = FileSystem.getLocal(job);

        // Test with no path
        initFiles(fs, 0, -1);
        assertEquals(0, format.getSplits(job, 2).length);

        // Test with 2 path and 4 splits
        initFiles(fs, 2, 500);
        assertEquals(2, format.getSplits(job, 4).length);
    }

    public static void main(String[] args) throws Exception {
        TestMultiFileInputFormat test = new TestMultiFileInputFormat();
        test.testFormat();
    }
}