1 /*
   2  * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import java.util.zip.CRC32;
  25 
  26 /**
  27  * Checksum provides methods for calculating a CRC32 value for a
  28  * transitions table.
  29  *
  30  * @since 1.4
  31  */
  32 public class Checksum extends CRC32
  33 {
  34     /**
  35      * Updates the CRC32 value from each byte of the given int
  36      * value. The bytes are used in the big endian order.
  37      * @param val the int value
  38      */
  39     public void update(int val) {
  40         byte[] b = new byte[4];
  41         b[0] = (byte)((val >>> 24) & 0xff);
  42         b[1] = (byte)((val >>> 16) & 0xff);
  43         b[2] = (byte)((val >>> 8) & 0xff);
  44         b[3] = (byte)(val & 0xff);
  45         update(b);
  46     }
  47 
  48     /**
  49      * Updates the CRC32 value from each byte of the given long
  50      * value. The bytes are used in the big endian order.
  51      * @param val the long value
  52      */
  53     void update(long val) {
  54         byte[] b = new byte[8];
  55         b[0] = (byte)((val >>> 56) & 0xff);
  56         b[1] = (byte)((val >>> 48) & 0xff);
  57         b[2] = (byte)((val >>> 40) & 0xff);
  58         b[3] = (byte)((val >>> 32) & 0xff);
  59         b[4] = (byte)((val >>> 24) & 0xff);
  60         b[5] = (byte)((val >>> 16) & 0xff);
  61         b[6] = (byte)((val >>> 8) & 0xff);
  62         b[7] = (byte)(val & 0xff);
  63         update(b);
  64     }
  65 }