infinispan.org.iq80.leveldb.util.Snappy Maven / Gradle / Ivy
package org.iq80.leveldb.util;
import java.io.IOException;
import java.nio.ByteBuffer;
/**
*
* A Snappy abstraction which attempts uses the iq80 implementation and falls back
* to the xerial Snappy implementation it cannot be loaded. You can change the
* load order by setting the 'leveldb.snappy' system property. Example:
*
*
* -Dleveldb.snappy=xerial,iq80
*
*
* The system property can also be configured with the name of a class which
* implements the Snappy.SPI interface.
*
*
* @author Hiram Chirino
*/
public class Snappy {
public static interface SPI {
public int uncompress(ByteBuffer compressed, ByteBuffer uncompressed) throws IOException;
public int uncompress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException;
public int compress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException;
public byte[] compress(String text) throws IOException;
public int maxCompressedLength(int length);
}
public static class XerialSnappy implements SPI {
static {
// Make sure that the JNI libs are fully loaded.
try {
org.xerial.snappy.Snappy.compress("test");
} catch (IOException e) {
throw new RuntimeException(e);
}
}
public int uncompress(ByteBuffer compressed, ByteBuffer uncompressed) throws IOException {
return org.xerial.snappy.Snappy.uncompress(compressed, uncompressed);
}
public int uncompress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException {
return org.xerial.snappy.Snappy.uncompress(input, inputOffset, length, output, outputOffset);
}
public int compress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException {
return org.xerial.snappy.Snappy.compress(input, inputOffset, length, output, outputOffset);
}
public byte[] compress(String text) throws IOException {
return org.xerial.snappy.Snappy.compress(text);
}
public int maxCompressedLength(int length) {
return org.xerial.snappy.Snappy.maxCompressedLength(length);
}
}
public static class IQ80Snappy implements SPI {
static {
// Make sure that the library can fully load.
try {
new IQ80Snappy().compress("test");
} catch (IOException e) {
throw new RuntimeException(e);
}
}
public int uncompress(ByteBuffer compressed, ByteBuffer uncompressed) throws IOException {
byte[] input;
int inputOffset;
int length;
byte[] output;
int outputOffset;
if( compressed.hasArray() ) {
input = compressed.array();
inputOffset = compressed.arrayOffset() + compressed.position();
length = compressed.remaining();
} else {
input = new byte[compressed.remaining()];
inputOffset = 0;
length = input.length;
compressed.mark();
compressed.get(input);
compressed.reset();
}
if( uncompressed.hasArray() ) {
output = uncompressed.array();
outputOffset = uncompressed.arrayOffset() + uncompressed.position();
} else {
int t = org.iq80.snappy.Snappy.getUncompressedLength(input, inputOffset);
output = new byte[t];
outputOffset = 0;
}
int count = org.iq80.snappy.Snappy.uncompress(input, inputOffset, length, output, outputOffset);
if( uncompressed.hasArray() ) {
uncompressed.limit(uncompressed.position()+count);
} else {
int p = uncompressed.position();
uncompressed.limit(uncompressed.capacity());
uncompressed.put(output, 0, count);
uncompressed.flip().position(p);
}
return count;
}
public int uncompress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException {
return org.iq80.snappy.Snappy.uncompress(input, inputOffset, length, output, outputOffset);
}
public int compress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException {
return org.iq80.snappy.Snappy.compress(input, inputOffset, length, output, outputOffset);
}
public byte[] compress(String text) throws IOException {
byte[] uncomressed = text.getBytes("UTF-8");
byte[] compressedOut = new byte[maxCompressedLength(uncomressed.length)];
int compressedSize = compress(uncomressed, 0, uncomressed.length, compressedOut, 0);
byte[] trimmedBuffer = new byte[compressedSize];
System.arraycopy(compressedOut, 0, trimmedBuffer, 0, compressedSize);
return trimmedBuffer;
}
public int maxCompressedLength(int length) {
return org.iq80.snappy.Snappy.maxCompressedLength(length);
}
}
static final private SPI SNAPPY;
static {
SPI attempt = null;
String[] factories = System.getProperty("leveldb.snappy", "iq80,xerial").split(",");
for (int i = 0; i < factories.length && attempt==null; i++) {
String name = factories[i];
try {
name = name.trim();
if("xerial".equals(name.toLowerCase())) {
name = "org.iq80.leveldb.util.Snappy$XerialSnappy";
} else if("iq80".equals(name.toLowerCase())) {
name = "org.iq80.leveldb.util.Snappy$IQ80Snappy";
}
attempt = (SPI) Thread.currentThread().getContextClassLoader().loadClass(name).newInstance();
} catch (Throwable e) {
}
}
SNAPPY = attempt;
}
public static boolean available() {
return SNAPPY !=null;
}
public static void uncompress(ByteBuffer compressed, ByteBuffer uncompressed) throws IOException {
SNAPPY.uncompress(compressed, uncompressed);
}
public static void uncompress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException {
SNAPPY.uncompress(input, inputOffset, length, output, outputOffset);
}
public static int compress(byte[] input, int inputOffset, int length, byte[] output, int outputOffset) throws IOException {
return SNAPPY.compress(input, inputOffset, length, output, outputOffset);
}
public static byte[] compress(String text) throws IOException {
return SNAPPY.compress(text);
}
public static int maxCompressedLength(int length) {
return SNAPPY.maxCompressedLength(length);
}
}