1 /* 2 * ==================================================================== 3 * The Apache Software License, Version 1.1 4 * 5 * Copyright (c) 2000 The Apache Software Foundation. All rights 6 * reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. The end-user documentation included with the redistribution, 21 * if any, must include the following acknowledgment: 22 * "This product includes software developed by the 23 * Apache Software Foundation (http://www.apache.org/)." 24 * Alternately, this acknowledgment may appear in the software itself, 25 * if and wherever such third-party acknowledgments normally appear. 26 * 27 * 4. The names "Apache" and "Apache Software Foundation" must 28 * not be used to endorse or promote products derived from this 29 * software without prior written permission. For written 30 * permission, please contact apache@apache.org. 31 * 32 * 5. Products derived from this software may not be called "Apache", 33 * nor may "Apache" appear in their name, without prior written 34 * permission of the Apache Software Foundation. 35 * 36 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED 37 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 38 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 39 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR 40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 42 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 43 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 44 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 45 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 46 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 47 * SUCH DAMAGE. 48 * ==================================================================== 49 * 50 * This software consists of voluntary contributions made by many 51 * individuals on behalf of the Apache Software Foundation. For more 52 * information on the Apache Software Foundation, please see 53 * <http://www.apache.org/>. 54 * 55 */ 56 package org.apache.poi.hpsf; 57 58 import java.io.*; 59 import org.apache.poi.util.LittleEndian; 60 61 /** 62 * <p>Represents a class ID (16 bytes). Unlike other little-endian 63 * type the {@link ClassID} is not just 16 bytes stored in the wrong 64 * order. Instead, it is a double word (4 bytes) followed by two 65 * words (2 bytes each) followed by 8 bytes.</p> 66 * 67 * @author Rainer Klute (klute@rainer-klute.de) 68 * @version $Id: ClassID.java,v 1.4 2002/07/17 16:23:22 klute Exp $ 69 * @since 2002-02-09 70 */ 71 public class ClassID 72 { 73 74 /** 75 * <p>The bytes making out the class ID in correct order, 76 * i.e. big-endian.</p> 77 */ 78 protected byte[] bytes; 79 80 81 82 /** 83 * <p>Creates a {@link ClassID} and reads its value from a byte 84 * array.</p> 85 * 86 * @param src The byte array to read from. 87 * @param offset The offset of the first byte to read. 88 */ 89 public ClassID(final byte[] src, final int offset) 90 { 91 read(src, offset); 92 } 93 94 95 96 public final static int LENGTH = 16; 97 98 public int length() 99 { 100 return LENGTH; 101 } 102 103 104 105 /** 106 * <p>Gets the bytes making out the class ID. They are returned in 107 * correct order, i.e. big-endian.</p> 108 */ 109 public byte[] getBytes() 110 { 111 return bytes; 112 } 113 114 115 116 /** 117 * <p>Reads a class ID from a byte array by turning little-endian 118 * into big-endian.</p> 119 * 120 * @param src The byte array to read from 121 * 122 * @param offset The offset within the <var>src</var> byte array 123 * 124 * @return A byte array containing the class ID. 125 */ 126 public byte[] read(final byte[] src, final int offset) 127 { 128 bytes = new byte[16]; 129 130 /* Read double word. */ 131 bytes[0] = src[3 + offset]; 132 bytes[1] = src[2 + offset]; 133 bytes[2] = src[1 + offset]; 134 bytes[3] = src[0 + offset]; 135 136 /* Read first word. */ 137 bytes[4] = src[5 + offset]; 138 bytes[5] = src[4 + offset]; 139 140 /* Read second word. */ 141 bytes[6] = src[7 + offset]; 142 bytes[7] = src[6 + offset]; 143 144 /* Read 8 bytes. */ 145 for (int i = 8; i < 16; i++) 146 bytes[i] = src[i + offset]; 147 148 return bytes; 149 } 150 151 } 152