001 /* JAPI - (Yet anothr (hopefully) useful) Java API
002 *
003 * Copyright (C) 2004-2006 Christian Hujer
004 *
005 * This program is free software; you can redistribute it and/or
006 * modify it under the terms of the GNU General Public License as
007 * published by the Free Software Foundation; either version 2 of the
008 * License, or (at your option) any later version.
009 *
010 * This program is distributed in the hope that it will be useful, but
011 * WITHOUT ANY WARRANTY; without even the implied warranty of
012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
013 * General Public License for more details.
014 *
015 * You should have received a copy of the GNU General Public License
016 * along with this program; if not, write to the Free Software
017 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
018 * 02111-1307, USA.
019 */
020
021 package net.sf.japi.util;
022
023 /** Class to convert data from little endian to big endian and vice versa.
024 * Since the conversion is symmetric, there are no special conversion methods, just generic ones, e.g. the same method is used to convert a little
025 * endian integer to a big endian integer and vice versa.
026 * @author <a href="mailto:Christian.Hujer@itcqis.com">Christian Hujer</a>
027 */
028 public class EndianConverter {
029
030 /** Convert a double.
031 * This method changes byte order from 1, 2, 3, 4, 5, 6, 7, 8 to 8, 7, 6, 5, 4, 3, 2, 1.
032 * @param d double to convert
033 * @return converted double
034 */
035 public static final double se(final double d) {
036 return Double.longBitsToDouble(se(Double.doubleToRawLongBits(d)));
037 }
038
039 /** Convert a float.
040 * This method changes byte order from 1, 2, 3, 4 to 4, 3, 2, 1.
041 * @param f float to convert
042 * @return converted float
043 */
044 public static final float se(final float f) {
045 return Float.intBitsToFloat(se(Float.floatToRawIntBits(f)));
046 }
047
048 /** Convert a long.
049 * This method changes byte order from 1, 2, 3, 4, 5, 6, 7, 8 to 8, 7, 6, 5, 4, 3, 2, 1.
050 * @param l long to convert
051 * @return converted long
052 */
053 public static final long se(final long l) {
054 return
055 (l & 0x00000000000000FFl) << 56 |
056 (l & 0x000000000000FF00l) << 40 |
057 (l & 0x0000000000FF0000l) << 24 |
058 (l & 0x00000000FF000000l) << 8 |
059 (l & 0x000000FF00000000l) >>> 8 |
060 (l & 0x0000FF0000000000l) >>> 24 |
061 (l & 0x00FF000000000000l) >>> 40 |
062 (l & 0xFF00000000000000l) >>> 56;
063 }
064
065 /** Convert an int.
066 * This method changes byte order from 1, 2, 3, 4 to 4, 3, 2, 1.
067 * @param i int to convert
068 * @return converted int
069 */
070 public static final int se(final int i) {
071 return
072 (i & 0x000000FF) << 24 |
073 (i & 0x0000FF00) << 8 |
074 (i & 0x00FF0000) >>> 8 |
075 (i & 0xFF000000) >>> 24;
076 }
077
078 /** Convert a char.
079 * This method swaps low and high byte.
080 * @param c char to convert
081 * @return converted char
082 */
083 public static final char se(final char c) {
084 return (char)
085 ((c & 0x00FF) << 8 |
086 (c & 0xFF00) >>> 8);
087 }
088
089 /** Convert a short.
090 * This method swaps low and high byte.
091 * @param s short to convert
092 * @return converted short
093 */
094 public static final short se(final short s) {
095 return (short)
096 ((s & 0x00FF) << 8 |
097 (s & 0xFF00) >>> 8);
098 }
099
100 /** Convert a byte.
101 * This method does nothing and exists for convenience only.
102 * @param b byte to convert
103 * @return converted byte (same as b)
104 */
105 public static final byte se(final byte b) {
106 return b;
107 }
108
109 /** Convert a boolean.
110 * This method does nothing and exists for convenience only.
111 * @param b boolean to convert
112 * @return converted boolean (same as b)
113 */
114 public static final boolean se(final boolean b) {
115 return b;
116 }
117
118 } // class EndianConverter