001 /* $RCSfile: IntegerUtil.java,v $
002 * $Revision: 1.3 $
003 * $Date: 2002/01/04 14:05:31 $
004 * $Author: uwe $
005 * $State: Exp $
006 *
007 * Created on July 12, 2001, 5:20 PM
008 *
009 * Copyright (C) 2001 Uwe Guenther <uwe@cscc.de>
010 *
011 * This file is part of the jhbci JCE-ServiceProvider. The jhbci JCE-
012 * ServiceProvider is a library, written in JavaTM, that should be
013 * used in HBCI banking applications (clients and may be servers),
014 * to do cryptographic operations.
015 *
016 * The jhbci library is free software; you can redistribute it and/or
017 * modify it under the terms of the GNU Lesser General Public
018 * License as published by the Free Software Foundation; either
019 * version 2.1 of the License, or (at your option) any later version.
020 *
021 * The jhbci library is distributed in the hope that it will be useful,
022 * but WITHOUT ANY WARRANTY; without even the implied warranty of
023 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
024 * Lesser General Public License for more details.
025 *
026 * You should have received a copy of the GNU Lesser General Public
027 * License along with this library; if not, write to the Free Software
028 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
029 *
030 */
031
032 package de.cscc.crypto.util;
033
034 /**
035 * IntegerUtil Class.
036 *
037 * Class that hold only static methods to convert ints and int arrays to
038 * Strings. These Strings holds the hex or binary representation of the
039 * converted ints or int arrays. This class can't be instance, because
040 * its constructor is private.
041 *
042 * @author <a href=mailto:uwe@cscc.de>Uwe Günther</a>
043 * @version $Revision: 1.3 $
044 */
045 public final class IntegerUtil {
046
047 /** This class can't be instance, because its constructor is private. */
048 private IntegerUtil() {}
049
050 /**
051 * Converts byte to binary representation.
052 *
053 * @param in int that will be converted.
054 * @return String with hex representation of in.
055 */
056 public static String toBin(int in){
057
058 return toBinGeneric(in);
059 }
060
061 /**
062 * Converts int[] to binary representation.
063 *
064 * @param in int[] that will be converted.
065 * @return String with hex representation of in.
066 */
067 public static String toBin(int[] in){
068
069 StringBuffer tmp = new StringBuffer();
070
071 for (int i = 0; i < in.length; i++) {
072 tmp.append(toBin(in[i]) + " ");
073 }
074
075 return "[ " + tmp + "]";
076
077 }
078
079 /**
080 * Converts int to binary representation.
081 *
082 * @param in int that will be converted
083 * @return String with hex representation of in
084 */
085 private static String toBinGeneric(int in){
086
087 StringBuffer tmp = new StringBuffer();
088
089 for(int i = 0; i < 32; i++){
090 tmp.insert(0, (in >>> i) & 0x00000001);
091
092 }
093
094 return "0b" + tmp.toString();
095 }
096
097 /**
098 * Converts int to hex representation.
099 *
100 * @param in int that will be converted.
101 * @return String with hex representation of in.
102 */
103 public static String toHex(int in) {
104
105 return toHexGeneric(in);
106 }
107
108 /**
109 * Converts int[] to hex representation.
110 *
111 * @param in int[] that will be converted.
112 * @return String with hex representation of in.
113 */
114 public static String toHex(int[] in) {
115
116 StringBuffer tmp = new StringBuffer();
117
118 for (int i = 0; i < in.length; i++) {
119 tmp.append(toHexGeneric(in[i]) + " ");
120 }
121
122 return "[ " + tmp.toString() + "]";
123 }
124
125 /**
126 * Converts int to binary representation.
127 *
128 * @param in int that will be converted
129 * @return String with hex representation of in
130 */
131 private static String toHexGeneric(int in){
132 return ByteUtil.toHex(toByteArray(in));
133 }
134
135 /**
136 * Converts int to byte[4]
137 *
138 * @param in int that should be converted to byte[4].
139 * @return byte array that holds the int in.
140 */
141 public static byte[] toByteArray(int in) {
142
143 byte[] temp = new byte[4];
144
145 temp[0] = (byte)((in >>> 24) & 0xff);
146 temp[1] = (byte)((in >>> 16) & 0xff);
147 temp[2] = (byte)((in >>> 8) & 0xff);
148 temp[3] = (byte)((in >>> 0) & 0xff);
149
150 return temp;
151 }
152 }