FileInputStream fis = new FileInputStream(blockFile);
fis.read(compressedBuffer);
fis.close();
BlockGunzipper gunzipper = new BlockGunzipper();
gunzipper.setCheckCrcs(true);
Method unzipBlock = BlockGunzipper.class.getDeclaredMethod("unzipBlock",byte[].class,byte[].class,Integer.TYPE);
unzipBlock.setAccessible(true);
unzipBlock.invoke(gunzipper,uncompressedBuffer,compressedBuffer,compressedBufferSize);