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 /**
  22  * A mutable SHA-1 abstraction.
  23  */
  24 public class MutableObjectId extends AnyObjectId {
  25         /**
  26          * Convert an ObjectId from raw binary representation.
  27          *
  28          * @param bs
  29          *            the raw byte buffer to read from. At least 20 bytes must be
  30          *            available within this byte array.
  31          */
  32         public void fromRaw(final byte[] bs) {
  33                 fromRaw(bs, 0);
  34         }
  35
  36         /**
  37          * Convert an ObjectId from raw binary representation.
  38          *
  39          * @param bs
  40          *            the raw byte buffer to read from. At least 20 bytes after p
  41          *            must be available within this byte array.
  42          * @param p
  43          *            position to read the first byte of data from.
  44          */
  45         public void fromRaw(final byte[] bs, final int p) {
  46                 w1 = rawUInt32(bs, p);
  47                 w2 = rawUInt32(bs, p + 4);
  48                 w3 = rawUInt32(bs, p + 8);
  49                 w4 = rawUInt32(bs, p + 12);
  50                 w5 = rawUInt32(bs, p + 16);
  51         }
  52
  53         /**
  54          * Convert an ObjectId from hex characters (US-ASCII).
  55          *
  56          * @param buf
  57          *            the US-ASCII buffer to read from. At least 40 bytes after
  58          *            offset must be available within this byte array.
  59          * @param offset
  60          *            position to read the first character from.
  61          */
  62         public void fromString(final byte[] buf, final int offset) {
  63                 fromHexString(buf, offset);
  64         }
  65
  66         /**
  67          * Convert an ObjectId from hex characters.
  68          *
  69          * @param str
  70          *            the string to read from. Must be 40 characters long.
  71          */
  72         public void fromString(final String str) {
  73                 if (str.length() != STR_LEN)
  74                         throw new IllegalArgumentException("Invalid id: " + str);
  75                 fromHexString(Constants.encodeASCII(str), 0);
  76         }
  77
  78         private void fromHexString(final byte[] bs, int p) {
  79                 try {
  80                         w1 = hexUInt32(bs, p);
  81                         w2 = hexUInt32(bs, p + 8);
  82                         w3 = hexUInt32(bs, p + 16);
  83                         w4 = hexUInt32(bs, p + 24);
  84                         w5 = hexUInt32(bs, p + 32);
  85                 } catch (ArrayIndexOutOfBoundsException e1) {
  86                         try {
  87                                 final String str = new String(bs, p, STR_LEN, "US-ASCII");
  88                                 throw new IllegalArgumentException("Invalid id: " + str);
  89                         } catch (UnsupportedEncodingException e2) {
  90                                 throw new IllegalArgumentException("Invalid id");
  91                         }
  92                 }
  93         }
  94
  95         @Override
  96         public ObjectId toObjectId() {
  97                 return new ObjectId(this);
  98         }
  99 }