压缩技术Zlib

         压缩技术 zlib 

         为了缓解网络传输的压力及对内容的安全性的考虑，使用了zlib 对包体进行了压缩、解压缩特地记录代码

 

ZLibUtils 写道

public class ZLibUtils {
private static Logger log = Logger.getLogger("ZLibUtils.class");
/**
* 压缩字节数组
* @param data
* @return
*/
public static byte[] compress(byte[] data){
byte[] compressByteData = new byte[0];

Deflater compress = new Deflater(Deflater.DEFAULT_COMPRESSION);
compress.reset();
compress.setInput(data);
compress.finish();
ByteArrayOutputStream bos = new ByteArrayOutputStream(data.length);
try {
byte[] buf = new byte[1024];
while(!compress.finished()){
int i = compress.deflate(buf);
bos.write(buf,0,i);
}
} catch (Exception e) {
// TODO Auto-generated catch block
compressByteData = data;
log.error("压缩数据异常："+e.getMessage());
e.printStackTrace();
}finally{
try {
bos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
log.error("压缩数据,关闭流异常："+e.getMessage());
}
}
compressByteData = bos.toByteArray();
compress.end();
return compressByteData;
}

public static void compress(byte[] data, OutputStream os){
DeflaterOutputStream dos = new DeflaterOutputStream(os);
try {
dos.write(data,0, data.length);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
log.error("压缩数据异常："+e.getMessage());
}finally{
try {
dos.close();

} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
log.error("压缩数据,关闭流异常："+e.getMessage());
}
}


}

public static byte[] decompress(byte[] data){
byte[] decompressByteData = new byte[0];
Inflater decompress = new Inflater();
decompress.reset();
decompress.setInput(data);
ByteArrayOutputStream bos = new ByteArrayOutputStream(data.length);
byte[] buf = new byte[1024];
try {
while (!decompress.finished()) {
int i = decompress.inflate(buf);
bos.write(buf,0,i);
}
decompressByteData = bos.toByteArray();
} catch (DataFormatException e) {
// TODO Auto-generated catch block
e.printStackTrace();
decompressByteData = data;
log.error("解压缩数据异常："+e.getMessage());
}finally{
try {
bos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
log.error("解压缩数据，关闭流异常："+e.getMessage());
}

}
decompress.end();
return decompressByteData;
}

public static byte[] decompress(InputStream is){
byte[] decompressByteData = new byte[0];
InflaterInputStream iis = new InflaterInputStream(is);
ByteArrayOutputStream bos = new ByteArrayOutputStream(1024);
try {
int i = 1024;
byte[] buf = new byte[i];
while ((i = iis.read(buf, 0, i)) > 0) {
bos.write(buf, 0, i);
}
decompressByteData = bos.toByteArray();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
log.error("解压缩数据异常："+e.getMessage());
}finally{
try {
bos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
log.error("解压缩数据，关闭流异常："+e.getMessage());
}
}

return decompressByteData;
}
}