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

   1 /*
   2  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
   3  *
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or
   7  * without modification, are permitted provided that the following
   8  * conditions are met:
   9  *
  10  * - Redistributions of source code must retain the above copyright
  11  *   notice, this list of conditions and the following disclaimer.
  12  *
  13  * - Redistributions in binary form must reproduce the above
  14  *   copyright notice, this list of conditions and the following
  15  *   disclaimer in the documentation and/or other materials provided
  16  *   with the distribution.
  17  *
  18  * - Neither the name of the Git Development Community nor the
  19  *   names of its contributors may be used to endorse or promote
  20  *   products derived from this software without specific prior
  21  *   written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  24  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  25  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  31  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  32  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  33  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  35  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 package org.spearce.jgit.lib;
  39
  40 import java.io.UnsupportedEncodingException;
  41
  42 import org.spearce.jgit.util.NB;
  43 import org.spearce.jgit.util.RawParseUtils;
  44
  45 /**
  46  * A mutable SHA-1 abstraction.
  47  */
  48 public class MutableObjectId extends AnyObjectId {
  49         /**
  50          * Empty constructor. Initialize object with default (zeros) value.
  51          */
  52         public MutableObjectId() {
  53                 super();
  54         }
  55
  56         /**
  57          * Copying constructor.
  58          *
  59          * @param src
  60          *            original entry, to copy id from
  61          */
  62         MutableObjectId(MutableObjectId src) {
  63                 this.w1 = src.w1;
  64                 this.w2 = src.w2;
  65                 this.w3 = src.w3;
  66                 this.w4 = src.w4;
  67                 this.w5 = src.w5;
  68         }
  69
  70         /** Make this id match {@link ObjectId#zeroId()}. */
  71         public void clear() {
  72                 w1 = 0;
  73                 w2 = 0;
  74                 w3 = 0;
  75                 w4 = 0;
  76                 w5 = 0;
  77         }
  78
  79         /**
  80          * Convert an ObjectId from raw binary representation.
  81          *
  82          * @param bs
  83          *            the raw byte buffer to read from. At least 20 bytes must be
  84          *            available within this byte array.
  85          */
  86         public void fromRaw(final byte[] bs) {
  87                 fromRaw(bs, 0);
  88         }
  89
  90         /**
  91          * Convert an ObjectId from raw binary representation.
  92          *
  93          * @param bs
  94          *            the raw byte buffer to read from. At least 20 bytes after p
  95          *            must be available within this byte array.
  96          * @param p
  97          *            position to read the first byte of data from.
  98          */
  99         public void fromRaw(final byte[] bs, final int p) {
 100                 w1 = NB.decodeInt32(bs, p);
 101                 w2 = NB.decodeInt32(bs, p + 4);
 102                 w3 = NB.decodeInt32(bs, p + 8);
 103                 w4 = NB.decodeInt32(bs, p + 12);
 104                 w5 = NB.decodeInt32(bs, p + 16);
 105         }
 106
 107         /**
 108          * Convert an ObjectId from binary representation expressed in integers.
 109          *
 110          * @param ints
 111          *            the raw int buffer to read from. At least 5 integers must be
 112          *            available within this integers array.
 113          */
 114         public void fromRaw(final int[] ints) {
 115                 fromRaw(ints, 0);
 116         }
 117
 118         /**
 119          * Convert an ObjectId from binary representation expressed in integers.
 120          *
 121          * @param ints
 122          *            the raw int buffer to read from. At least 5 integers after p
 123          *            must be available within this integers array.
 124          * @param p
 125          *            position to read the first integer of data from.
 126          *
 127          */
 128         public void fromRaw(final int[] ints, final int p) {
 129                 w1 = ints[p];
 130                 w2 = ints[p + 1];
 131                 w3 = ints[p + 2];
 132                 w4 = ints[p + 3];
 133                 w5 = ints[p + 4];
 134         }
 135
 136         /**
 137          * Convert an ObjectId from hex characters (US-ASCII).
 138          *
 139          * @param buf
 140          *            the US-ASCII buffer to read from. At least 40 bytes after
 141          *            offset must be available within this byte array.
 142          * @param offset
 143          *            position to read the first character from.
 144          */
 145         public void fromString(final byte[] buf, final int offset) {
 146                 fromHexString(buf, offset);
 147         }
 148
 149         /**
 150          * Convert an ObjectId from hex characters.
 151          *
 152          * @param str
 153          *            the string to read from. Must be 40 characters long.
 154          */
 155         public void fromString(final String str) {
 156                 if (str.length() != STR_LEN)
 157                         throw new IllegalArgumentException("Invalid id: " + str);
 158                 fromHexString(Constants.encodeASCII(str), 0);
 159         }
 160
 161         private void fromHexString(final byte[] bs, int p) {
 162                 try {
 163                         w1 = RawParseUtils.parseHexInt32(bs, p);
 164                         w2 = RawParseUtils.parseHexInt32(bs, p + 8);
 165                         w3 = RawParseUtils.parseHexInt32(bs, p + 16);
 166                         w4 = RawParseUtils.parseHexInt32(bs, p + 24);
 167                         w5 = RawParseUtils.parseHexInt32(bs, p + 32);
 168                 } catch (ArrayIndexOutOfBoundsException e1) {
 169                         try {
 170                                 final String str = new String(bs, p, STR_LEN, "US-ASCII");
 171                                 throw new IllegalArgumentException("Invalid id: " + str);
 172                         } catch (UnsupportedEncodingException e2) {
 173                                 throw new IllegalArgumentException("Invalid id");
 174                         } catch (StringIndexOutOfBoundsException e2) {
 175                                 throw new IllegalArgumentException("Invalid id");
 176                         }
 177                 }
 178         }
 179
 180         @Override
 181         public ObjectId toObjectId() {
 182                 return new ObjectId(this);
 183         }
 184 }