import java.util.zip.Deflater;

import java.util.zip.Inflater;

public class ZipUtil {

public static final int BUF_SIZE = 1024;

public static ZipUtil instance = null;

private ZipUtil() {

}

public static ZipUtil getInstance() {

if (instance == null)

instance = new ZipUtil();

return instance;

}

public byte[] compress(byte[] input) {

if (input == null)

return null;

byte[] buf = new byte[BUF_SIZE];

ByteArrayOutputStream baos = new ByteArrayOutputStream();

Deflater def = new Deflater();

def.setInput(input);

def.finish();

try {

while (!def.finished()) {

int count = def.deflate(buf);

baos.write(buf, 0, count);

}

} catch (Exception e) {

e.printStackTrace();

} finally {

def.end();

}

return baos.toByteArray();

}

public byte[] decompress(byte[] input) {

if (input == null)

return null;

byte[] buf = new byte[BUF_SIZE];

ByteArrayOutputStream baos = new ByteArrayOutputStream();

Inflater inf = new Inflater();

inf.setInput(input);

try {

while (true) {

int count = inf.inflate(buf);

if (count > 0) {

baos.write(buf, 0, count);

} else if (count == 0 && inf.finished()) {

break;

} else {

throw new RuntimeException();

}

}

} catch (Exception e) {

e.printStackTrace();

} finally {

inf.end();

}

return baos.toByteArray();

}

}