org.spearce.jgit/src/org/spearce/jgit/lib/MutableObjectId.java

   1 /*
   2  *  Copyright (C) 2008  Shawn Pearce <spearce@spearce.org>
   3  *
   4  *  This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU General Public
   6  *  License, version 2, as published by the Free Software Foundation.
   7  *
   8  *  This library is distributed in the hope that it will be useful,
   9  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  *  General Public License for more details.
  12  *
  13  *  You should have received a copy of the GNU General Public
  14  *  License along with this library; if not, write to the Free Software
  15  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
  16  */
  17 package org.spearce.jgit.lib;
  18
  19 import java.io.UnsupportedEncodingException;
  20
  21 import org.spearce.jgit.util.NB;
  22
  23 /**
  24  * A mutable SHA-1 abstraction.
  25  */
  26 public class MutableObjectId extends AnyObjectId {
  27         /**
  28          * Convert an ObjectId from raw binary representation.
  29          *
  30          * @param bs
  31          *            the raw byte buffer to read from. At least 20 bytes must be
  32          *            available within this byte array.
  33          */
  34         public void fromRaw(final byte[] bs) {
  35                 fromRaw(bs, 0);
  36         }
  37
  38         /**
  39          * Convert an ObjectId from raw binary representation.
  40          *
  41          * @param bs
  42          *            the raw byte buffer to read from. At least 20 bytes after p
  43          *            must be available within this byte array.
  44          * @param p
  45          *            position to read the first byte of data from.
  46          */
  47         public void fromRaw(final byte[] bs, final int p) {
  48                 w1 = NB.decodeInt32(bs, p);
  49                 w2 = NB.decodeInt32(bs, p + 4);
  50                 w3 = NB.decodeInt32(bs, p + 8);
  51                 w4 = NB.decodeInt32(bs, p + 12);
  52                 w5 = NB.decodeInt32(bs, p + 16);
  53         }
  54
  55         /**
  56          * Convert an ObjectId from hex characters (US-ASCII).
  57          *
  58          * @param buf
  59          *            the US-ASCII buffer to read from. At least 40 bytes after
  60          *            offset must be available within this byte array.
  61          * @param offset
  62          *            position to read the first character from.
  63          */
  64         public void fromString(final byte[] buf, final int offset) {
  65                 fromHexString(buf, offset);
  66         }
  67
  68         /**
  69          * Convert an ObjectId from hex characters.
  70          *
  71          * @param str
  72          *            the string to read from. Must be 40 characters long.
  73          */
  74         public void fromString(final String str) {
  75                 if (str.length() != STR_LEN)
  76                         throw new IllegalArgumentException("Invalid id: " + str);
  77                 fromHexString(Constants.encodeASCII(str), 0);
  78         }
  79
  80         private void fromHexString(final byte[] bs, int p) {
  81                 try {
  82                         w1 = hexUInt32(bs, p);
  83                         w2 = hexUInt32(bs, p + 8);
  84                         w3 = hexUInt32(bs, p + 16);
  85                         w4 = hexUInt32(bs, p + 24);
  86                         w5 = hexUInt32(bs, p + 32);
  87                 } catch (ArrayIndexOutOfBoundsException e1) {
  88                         try {
  89                                 final String str = new String(bs, p, STR_LEN, "US-ASCII");
  90                                 throw new IllegalArgumentException("Invalid id: " + str);
  91                         } catch (UnsupportedEncodingException e2) {
  92                                 throw new IllegalArgumentException("Invalid id");
  93                         }
  94                 }
  95         }
  96
  97         @Override
  98         public ObjectId toObjectId() {
  99                 return new ObjectId(this);
 100         }
 101 }