/**
* 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.io.file.tfile;
import java.io.IOException;
import java.util.Random;
import org.junit.Assert;
import junit.framework.TestCase;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.BytesWritable;
import org.apache.hadoop.io.file.tfile.TFile.Reader;
import org.apache.hadoop.io.file.tfile.TFile.Writer;
import org.apache.hadoop.io.file.tfile.TFile.Reader.Scanner;
public class TestTFileSplit extends TestCase {
private static String ROOT =
System.getProperty("test.build.data", "/tmp/tfile-test");
private final static int BLOCK_SIZE = 64 * 1024;
private static final String KEY = "key";
private static final String VALUE = "value";
private FileSystem fs;
private Configuration conf;
private Path path;
private Random random = new Random();
private String comparator = "memcmp";
private String outputFile = "TestTFileSplit";
void createFile(int count, String compress) throws IOException {
conf = new Configuration();
path = new Path(ROOT, outputFile + "." + compress);
fs = path.getFileSystem(conf);
FSDataOutputStream out = fs.create(path);
Writer writer = new Writer(out, BLOCK_SIZE, compress, comparator, conf);
int nx;
for (nx = 0; nx < count; nx++) {
byte[] key = composeSortedKey(KEY, count, nx).getBytes();
byte[] value = (VALUE + nx).getBytes();
writer.append(key, value);
}
writer.close();
out.close();
}
void readFile() throws IOException {
long fileLength = fs.getFileStatus(path).getLen();
int numSplit = 10;
long splitSize = fileLength / numSplit + 1;
Reader reader =
new Reader(fs.open(path), fs.getFileStatus(path).getLen(), conf);
long offset = 0;
long rowCount = 0;
BytesWritable key, value;
for (int i = 0; i < numSplit; ++i, offset += splitSize) {
Scanner scanner = reader.createScannerByByteRange(offset, splitSize);
int count = 0;
key = new BytesWritable();
value = new BytesWritable();
while (!scanner.atEnd()) {
scanner.entry().get(key, value);
++count;
scanner.advance();
}
scanner.close();
Assert.assertTrue(count > 0);
rowCount += count;
}
Assert.assertEquals(rowCount, reader.getEntryCount());
reader.close();
}
/* Similar to readFile(), tests the scanner created
* by record numbers rather than the offsets.
*/
void readRowSplits(int numSplits) throws IOException {
Reader reader =
new Reader(fs.open(path), fs.getFileStatus(path).getLen(), conf);
long totalRecords = reader.getEntryCount();
for (int i=0; i<numSplits; i++) {
long startRec = i*totalRecords/numSplits;
long endRec = (i+1)*totalRecords/numSplits;
if (i == numSplits-1) {
endRec = totalRecords;
}
Scanner scanner = reader.createScannerByRecordNum(startRec, endRec);
int count = 0;
BytesWritable key = new BytesWritable();
BytesWritable value = new BytesWritable();
long x=startRec;
while (!scanner.atEnd()) {
assertEquals("Incorrect RecNum returned by scanner", scanner.getRecordNum(), x);
scanner.entry().get(key, value);
++count;
assertEquals("Incorrect RecNum returned by scanner", scanner.getRecordNum(), x);
scanner.advance();
++x;
}
scanner.close();
Assert.assertTrue(count == (endRec - startRec));
}
// make sure specifying range at the end gives zero records.
Scanner scanner = reader.createScannerByRecordNum(totalRecords, -1);
Assert.assertTrue(scanner.atEnd());
}
static String composeSortedKey(String prefix, int total, int value) {
return String.format("%s%010d", prefix, value);
}
void checkRecNums() throws IOException {
long fileLen = fs.getFileStatus(path).getLen();
Reader reader = new Reader(fs.open(path), fileLen, conf);
long totalRecs = reader.getEntryCount();
long begin = random.nextLong() % (totalRecs / 2);
if (begin < 0)
begin += (totalRecs / 2);
long end = random.nextLong() % (totalRecs / 2);
if (end < 0)
end += (totalRecs / 2);
end += (totalRecs / 2) + 1;
assertEquals("RecNum for offset=0 should be 0", 0, reader
.getRecordNumNear(0));
for (long x : new long[] { fileLen, fileLen + 1, 2 * fileLen }) {
assertEquals("RecNum for offset>=fileLen should be total entries",
totalRecs, reader.getRecordNumNear(x));
}
for (long i = 0; i < 100; ++i) {
assertEquals("Locaton to RecNum conversion not symmetric", i, reader
.getRecordNumByLocation(reader.getLocationByRecordNum(i)));
}
for (long i = 1; i < 100; ++i) {
long x = totalRecs - i;
assertEquals("Locaton to RecNum conversion not symmetric", x, reader
.getRecordNumByLocation(reader.getLocationByRecordNum(x)));
}
for (long i = begin; i < end; ++i) {
assertEquals("Locaton to RecNum conversion not symmetric", i, reader
.getRecordNumByLocation(reader.getLocationByRecordNum(i)));
}
for (int i = 0; i < 1000; ++i) {
long x = random.nextLong() % totalRecs;
if (x < 0) x += totalRecs;
assertEquals("Locaton to RecNum conversion not symmetric", x, reader
.getRecordNumByLocation(reader.getLocationByRecordNum(x)));
}
}
public void testSplit() throws IOException {
System.out.println("testSplit");
createFile(100000, Compression.Algorithm.NONE.getName());
checkRecNums();
readFile();
readRowSplits(10);
fs.delete(path, true);
createFile(500000, Compression.Algorithm.GZ.getName());
checkRecNums();
readFile();
readRowSplits(83);
fs.delete(path, true);
}
}