1 /*
2  * DeltaDecoder
3  *
4  * Author: Lasse Collin <lasse.collin@tukaani.org>
5  *
6  * This file has been put into the public domain.
7  * You can do whatever you want with this file.
8  */
9 
10 package org.tukaani.xz.delta;
11 
12 public class DeltaDecoder extends DeltaCoder {
DeltaDecoder(int distance)13     public DeltaDecoder(int distance) {
14         super(distance);
15     }
16 
decode(byte[] buf, int off, int len)17     public void decode(byte[] buf, int off, int len) {
18         int end = off + len;
19         for (int i = off; i < end; ++i) {
20             buf[i] += history[(distance + pos) & DISTANCE_MASK];
21             history[pos-- & DISTANCE_MASK] = buf[i];
22         }
23     }
24 }
25