snappy-java/src/test/java/org/xerial/snappy/SnappyOutputStreamTest.java
2015-05-14 00:30:53 -07:00

285 lines
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Java
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/*--------------------------------------------------------------------------
* Copyright 2011 Taro L. Saito
*
* Licensed 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.
*--------------------------------------------------------------------------*/
//--------------------------------------
// XerialJ
//
// SnappyOutputStreamTest.java
// Since: 2011/03/31 18:26:31
//
// $URL$
// $Author$
//--------------------------------------
package org.xerial.snappy;
import static org.junit.Assert.*;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import org.junit.Test;
import org.xerial.snappy.buffer.BufferAllocatorFactory;
import org.xerial.snappy.buffer.CachedBufferAllocator;
import org.xerial.util.FileResource;
import org.xerial.util.log.Logger;
public class SnappyOutputStreamTest
{
private static Logger _logger = Logger.getLogger(SnappyOutputStreamTest.class);
@Test
public void test() throws Exception {
ByteArrayOutputStream buf = new ByteArrayOutputStream();
SnappyOutputStream sout = new SnappyOutputStream(buf);
BufferedInputStream input = new BufferedInputStream(FileResource.find(SnappyOutputStreamTest.class,
"alice29.txt").openStream());
assertNotNull(input);
ByteArrayOutputStream orig = new ByteArrayOutputStream();
byte[] tmp = new byte[1024];
for (int readBytes = 0; (readBytes = input.read(tmp)) != -1;) {
sout.write(tmp, 0, readBytes);
orig.write(tmp, 0, readBytes); // preserve the original data
}
input.close();
sout.flush();
orig.flush();
int compressedSize = buf.size();
_logger.debug("compressed size: " + compressedSize);
ByteArrayOutputStream decompressed = new ByteArrayOutputStream();
byte[] compressed = buf.toByteArray();
// decompress
for (int cursor = SnappyCodec.headerSize(); cursor < compressed.length;) {
int chunkSize = SnappyOutputStream.readInt(compressed, cursor);
cursor += 4;
byte[] tmpOut = new byte[Snappy.uncompressedLength(compressed, cursor, chunkSize)];
int decompressedSize = Snappy.uncompress(compressed, cursor, chunkSize, tmpOut, 0);
cursor += chunkSize;
decompressed.write(tmpOut);
}
decompressed.flush();
assertEquals(orig.size(), decompressed.size());
assertArrayEquals(orig.toByteArray(), decompressed.toByteArray());
}
@Test
public void bufferSize() throws Exception {
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream os = new SnappyOutputStream(b, 1500);
final int bytesToWrite = 5000;
byte[] orig = new byte[bytesToWrite];
for (int i = 0; i < 5000; ++i) {
byte v = (byte) (i % 128);
orig[i] = v;
os.write(v);
}
os.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
byte[] buf = new byte[bytesToWrite / 101];
while (is.read(buf) != -1) {}
is.close();
}
@Test
public void smallWrites() throws Exception {
byte[] orig = CalgaryTest.readFile("alice29.txt");
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream out = new SnappyOutputStream(b);
for(byte c : orig) {
out.write(c);
}
out.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
byte[] decompressed = new byte[orig.length];
int cursor = 0;
int readLen = 0;
for(int i=0; i < decompressed.length && (readLen = is.read(decompressed, i, decompressed.length-i)) != -1; ) {
i += readLen;
}
is.close();
assertArrayEquals(orig, decompressed);
}
/**
* Compress the input array by passing it chunk-by-chunk to a SnappyOutputStream.
* @param orig the data to compress
* @param maxChunkSize the maximum chunk size, in bytes.
* @return the compressed bytes
*/
private static byte[] compressAsChunks(byte[] orig, int maxChunkSize) throws Exception {
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream out = new SnappyOutputStream(b);
int remaining = orig.length;
for (int start = 0; start < orig.length; start += maxChunkSize) {
out.write(orig, start, remaining < maxChunkSize ? remaining : maxChunkSize);
remaining -= maxChunkSize;
}
out.close();
return b.toByteArray();
}
@Test
public void batchingOfWritesShouldNotAffectCompressedDataSize() throws Exception {
// Regression test for issue #100, a bug where the size of compressed data could be affected
// by the batching of writes to the SnappyOutputStream rather than the total amount of data
// written to the stream.
byte[] orig = CalgaryTest.readFile("alice29.txt");
// Compress the data once so that we know the expected size:
byte[] expectedCompressedData = compressAsChunks(orig, Integer.MAX_VALUE);
// Hardcoding an expected compressed size here will catch regressions that lower the
// compression quality:
assertEquals(91013, expectedCompressedData.length);
// The chunk size should not affect the size of the compressed output:
int[] chunkSizes = new int[] { 1, 100, 1023, 1024, 10000};
for (int chunkSize : chunkSizes) {
byte[] compressedData = compressAsChunks(orig, chunkSize);
assertEquals(String.format("when chunk size = %,d", chunkSize), expectedCompressedData.length, compressedData.length);
assertArrayEquals(expectedCompressedData, compressedData);
}
}
@Test
public void closeShouldBeIdempotent() throws Exception {
// Regression test for issue #107, a bug where close() was non-idempotent and would release
// its buffers to the allocator multiple times, which could cause scenarios where two open
// SnappyOutputStreams could share the same buffers, leading to stream corruption issues.
final BufferAllocatorFactory bufferAllocatorFactory = CachedBufferAllocator.factory;
final int BLOCK_SIZE = 4096;
// Create a stream, use it, then close it once:
ByteArrayOutputStream ba1 = new ByteArrayOutputStream();
SnappyOutputStream os1 = new SnappyOutputStream(ba1, BLOCK_SIZE, bufferAllocatorFactory);
os1.write(42);
os1.close();
// Create a new output stream, which should end up re-using the first stream's freed buffers
ByteArrayOutputStream ba2 = new ByteArrayOutputStream();
SnappyOutputStream os2 = new SnappyOutputStream(ba2, BLOCK_SIZE, bufferAllocatorFactory);
// Close the first stream a second time, which is supposed to be safe due to idempotency:
os1.close();
// Allocate a third output stream, which is supposed to get its own fresh set of buffers:
ByteArrayOutputStream ba3 = new ByteArrayOutputStream();
SnappyOutputStream os3 = new SnappyOutputStream(ba3, BLOCK_SIZE, bufferAllocatorFactory);
// Since the second and third streams should have distinct sets of buffers, writes to these
// streams should not interfere with one another:
os2.write(2);
os3.write(3);
os2.close();
os3.close();
SnappyInputStream in2 = new SnappyInputStream(new ByteArrayInputStream(ba2.toByteArray()));
assertEquals(2, in2.read());
SnappyInputStream in3 = new SnappyInputStream(new ByteArrayInputStream(ba3.toByteArray()));
assertEquals(3, in3.read());
}
@Test
public void longArrayCompress() throws Exception {
long[] l = new long[10];
for (int i = 0; i < l.length; ++i) {
l[i] = i % 3 + i * 11;
}
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream os = new SnappyOutputStream(b);
os.write(l);
os.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
long[] l2 = new long[10];
int readBytes = is.read(l2);
is.close();
assertEquals(10 * 8, readBytes);
assertArrayEquals(l, l2);
}
@Test
public void writeDoubleArray() throws Exception {
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream os = new SnappyOutputStream(b);
double[] orig = new double[] { 1.0, 2.0, 1.4, 0.00343430014, -4.4, 4e-20 };
os.write(orig);
os.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
double[] uncompressed = new double[orig.length];
is.read(uncompressed);
is.close();
assertArrayEquals(orig, uncompressed, 0.0);
}
@Test
public void writeFloatArray() throws Exception {
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream os = new SnappyOutputStream(b);
float[] orig = new float[] { 1.0f, 2.0f, 1.4f, 0.00343430014f, -4.4f, 4e-20f };
os.write(orig);
os.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
float[] uncompressed = new float[orig.length];
is.read(uncompressed);
is.close();
assertArrayEquals(orig, uncompressed, 0.0f);
}
@Test
public void writeIntArray() throws Exception {
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream os = new SnappyOutputStream(b);
int[] orig = new int[] { 0, -1, -34, 43, 234, 34324, -234 };
os.write(orig);
os.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
int[] uncompressed = new int[orig.length];
is.read(uncompressed);
is.close();
assertArrayEquals(orig, uncompressed);
}
@Test
public void writeShortArray() throws Exception {
ByteArrayOutputStream b = new ByteArrayOutputStream();
SnappyOutputStream os = new SnappyOutputStream(b);
short[] orig = new short[] { 0, -1, -34, 43, 234, 324, -234 };
os.write(orig);
os.close();
SnappyInputStream is = new SnappyInputStream(new ByteArrayInputStream(b.toByteArray()));
short[] uncompressed = new short[orig.length];
is.read(uncompressed);
is.close();
assertArrayEquals(orig, uncompressed);
}
}