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1
24 package org.riotfamily.common.util;
25
26 import java.util.Random  ;
27
28
33 public class PasswordGenerator {
34
35 private static final String UPPER_CHARS = "ABCDEFGHJKLKMNPQRSTWXYZ";
36 private static final String AMBIGUOUS_UPPER_CHARS = "IOUV";
37
38 private static final String LOWER_CHARS = "abcdefghijkmnpqrstwxyz";
39 private static final String AMBIGUOUS_LOWER_CHARS = "louv";
40
41 private static final String DIGITS = "23456789";
42 private static final String AMBIGUOUS_DIGITS = "01";
43
44 private static PasswordGenerator defaultInstance = new PasswordGenerator();
45
46 private Random random = new Random ();
47
48 private boolean useUpperChars;
49 private boolean useLowerChars;
50 private boolean useDigits;
51
52 private boolean includeAmbiguous;
53
54 private int passwordLength;
55
56 private StringBuffer chars;
57
58 public PasswordGenerator() {
59 this(8, true, true, true);
60 }
61
62 public PasswordGenerator(
63 int passwordLength,
64 boolean useUpperChars,
65 boolean useLowerChars,
66 boolean useDigits) {
67
68 this.passwordLength = passwordLength;
69 this.useUpperChars = useUpperChars;
70 this.useLowerChars = useLowerChars;
71 this.useDigits = useDigits;
72 }
73
74 public static PasswordGenerator getDefaultInstance() {
75 return defaultInstance;
76 }
77
78 public boolean getUseUpperChars() {
79 return useUpperChars;
80 }
81
82 public boolean getUseLowerChars() {
83 return useLowerChars;
84 }
85
86 public boolean getUseDigits() {
87 return useDigits;
88 }
89
90 public boolean isIncludeAmbiguous() {
91 return includeAmbiguous;
92 }
93
94 public void setUseUpperChars(boolean v) {
95 check();
96 useUpperChars = v;
97 }
98
99 public void setUseLowerChars(boolean v) {
100 check();
101 useLowerChars = v;
102 }
103
104 public void setUseDigits(boolean v) {
105 check();
106 useDigits = v;
107 }
108
109 public void setIncludeAmbiguous(boolean includeAmbiguous) {
110 check();
111 this.includeAmbiguous = includeAmbiguous;
112 }
113
114 public void setPasswordLength(int i) {
115 passwordLength = i;
116 }
117
118 public int getPasswordLength() {
119 return passwordLength;
120 }
121
122 protected void check() {
123 if (chars != null) {
124 throw new IllegalStateException (
125 "PasswordGenerator is already configured");
126 }
127 }
128
129 protected void prepare() {
130 if (chars == null) {
131 chars = new StringBuffer ();
132 if (getUseLowerChars()) {
133 chars.append(LOWER_CHARS);
134 if (includeAmbiguous) {
135 chars.append(AMBIGUOUS_LOWER_CHARS);
136 }
137 }
138 if (getUseUpperChars()) {
139 chars.append(UPPER_CHARS);
140 if (includeAmbiguous) {
141 chars.append(AMBIGUOUS_UPPER_CHARS);
142 }
143 }
144 if (getUseDigits()) {
145 chars.append(DIGITS);
146 if (includeAmbiguous) {
147 chars.append(AMBIGUOUS_DIGITS);
148 }
149 }
150 if (chars.length() == 0) {
151 throw new IllegalStateException (
152 "At least one type of characters must be specified");
153 }
154 }
155 }
156
157 public long getPossibleCombinations() {
158 return (long) Math.pow(chars.length(),passwordLength);
159 }
160
161 public int getChanceToGuess(long validPasswords) {
162 return (int)(getPossibleCombinations() / validPasswords);
164 }
165
166 public String generate() {
167 prepare();
168 StringBuffer buffer = new StringBuffer (passwordLength);
169
170
173 for (int i = 0; i < passwordLength; i++) {
174 int index = random.nextInt() % chars.length();
175 index = Math.abs(index);
176 char c = chars.charAt(index);
177 buffer.append(c);
178 }
179 return buffer.toString();
180 }
181
182 }
183 |
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