1 /* 2 * DeltaCoder 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 abstract class DeltaCoder { 13 static final int DISTANCE_MIN = 1; 14 static final int DISTANCE_MAX = 256; 15 static final int DISTANCE_MASK = DISTANCE_MAX - 1; 16 17 final int distance; 18 final byte[] history = new byte[DISTANCE_MAX]; 19 int pos = 0; 20 DeltaCoder(int distance)21 DeltaCoder(int distance) { 22 if (distance < DISTANCE_MIN || distance > DISTANCE_MAX) 23 throw new IllegalArgumentException(); 24 25 this.distance = distance; 26 } 27 } 28