1 /* ==================================================================== 2 * The Apache Software License, Version 1.1 3 * 4 * Copyright (c) 2000 The Apache Software Foundation. All rights 5 * reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * 19 * 3. The end-user documentation included with the redistribution, 20 * if any, must include the following acknowledgment: 21 * "This product includes software developed by the 22 * Apache Software Foundation (http://www.apache.org/)." 23 * Alternately, this acknowledgment may appear in the software itself, 24 * if and wherever such third-party acknowledgments normally appear. 25 * 26 * 4. The names "Apache" and "Apache Software Foundation" must 27 * not be used to endorse or promote products derived from this 28 * software without prior written permission. For written 29 * permission, please contact apache@apache.org. 30 * 31 * 5. Products derived from this software may not be called "Apache", 32 * nor may "Apache" appear in their name, without prior written 33 * permission of the Apache Software Foundation. 34 * 35 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED 36 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 37 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 38 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR 39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 41 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 42 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 43 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 44 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 45 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 46 * SUCH DAMAGE. 47 * ==================================================================== 48 * 49 * This software consists of voluntary contributions made by many 50 * individuals on behalf of the Apache Software Foundation. For more 51 * information on the Apache Software Foundation, please see 52 * <http://www.apache.org/>. 53 * 54 * Portions of this software are based upon public domain software 55 * originally written at the National Center for Supercomputing Applications, 56 * University of Illinois, Urbana-Champaign. 57 */ 58 59 package org.apache.poi.hpsf.littleendian; 60 61 /** 62 * <p>A data item in the little-endian format. Little-endian means 63 * that lower bytes come before higher bytes.</p> 64 * 65 * @author Rainer Klute (klute@rainer-klute.de) 66 * @version $Id: LittleEndian.java,v 1.1 2002/02/14 04:00:59 mjohnson Exp $ 67 * @since 2002-02-09 68 */ 69 public abstract class LittleEndian 70 { 71 72 /* This class could be optimized by not copying the bytes, but 73 * instead maintaining just references to the original byte 74 * arrays. However, before implementing this it should be 75 * investigated whether it is worth the while. */ 76 77 78 /** 79 * <p>The bytes making out the little-endian field. They are in 80 * correct order, i.e. high-endian.</p> 81 */ 82 protected byte[] bytes; 83 84 85 86 /** 87 * <p>Creates a {@link LittleEndian} and reads its value from a 88 * byte array.</p> 89 * 90 * @param src The byte array to read from. 91 * 92 * @param offset The offset of the first byte to read. 93 */ 94 public LittleEndian(final byte[] src, final int offset) 95 { 96 read(src, offset); 97 } 98 99 100 101 /** 102 * <p>Returns the bytes making out the little-endian field in 103 * big-endian order. 104 </p> */ 105 public byte[] getBytes() 106 { 107 return bytes; 108 } 109 110 111 112 /** 113 * <p>Reads the little-endian field from a byte array.</p> 114 * 115 * @param src The byte array to read from 116 * 117 * @param offset The offset within the <var>src</var> byte array 118 */ 119 public byte[] read(final byte[] src, final int offset) 120 { 121 final int length = length(); 122 bytes = new byte[length]; 123 for (int i = 0; i < length; i++) 124 bytes[i] = src[offset + length - 1 - i]; 125 return bytes; 126 } 127 128 129 /** 130 * <p>Returns the number of bytes of this little-endian field.</p> 131 */ 132 public abstract int length(); 133 134 } 135