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1
25
28 package classycle;
29
30 import java.util.Collections  ;
31 import java.util.LinkedHashSet ;
32 import java.util.Set ;
33
34 import classycle.classfile.UTF8Constant;
35
36 class ClassNameExtractor
37 {
38
39 static boolean isValid(String className)
40 {
41 boolean valid = true;
42 boolean firstCharacter = true;
43 for (int i = 0, n = className.length(); valid && i < n; i++)
44 {
45 char c = className.charAt(i);
46 if (firstCharacter)
47 {
48 firstCharacter = false;
49 valid = Character.isJavaIdentifierStart(c);
50 } else
51 {
52 if (c == '.')
53 {
54 firstCharacter = true;
55 } else
56 {
57 valid = Character.isJavaIdentifierPart(c);
58 }
59 }
60 }
61 return valid && firstCharacter == false;
62 }
63
64 private final String _constant;
65
66 private int _index;
67 private int _endIndex;
68 private Set _classNames = new LinkedHashSet ();
69 private boolean _valid = true;
70
71 ClassNameExtractor(UTF8Constant constant)
72 {
73 _constant = constant.getString();
74 _endIndex = _constant.length();
75 }
76
77 Set extract()
78 {
79 if (getCurrentCharacter() == '<')
80 {
81 int ddIndex = _constant.indexOf("::", _index);
82 if (ddIndex > 0)
83 {
84 _index = ddIndex + 2;
85 parseTypes(false);
86 if (getCurrentCharacter() == '>')
87 {
88 _index++;
89 } else
90 {
91 setInvalid();
92 }
93 } else
94 {
95 setInvalid();
96 }
97 }
98 if (getCurrentCharacter() == '(')
99 {
100 int endIndex = _constant.indexOf(')', _index);
101 if (endIndex > 0)
102 {
103 _index++;
104 _endIndex = endIndex;
105 parseTypes(false);
106 _index = endIndex + 1;
107 _endIndex = _constant.length();
108 } else
109 {
110 setInvalid();
111 }
112 }
113 if (_valid)
114 {
115 int numberOfTypes = parseTypes(false);
116 if (numberOfTypes == 0)
117 {
118 setInvalid();
119 }
120 }
121 return _valid ? _classNames : Collections.EMPTY_SET;
122 }
123
124 private int parseTypes(boolean generics)
125 {
126 int numberOfTypes = 0;
127 while (_valid && endOfTypes() == false)
128 {
129 parseType(generics);
130 numberOfTypes++;
131 }
132 return numberOfTypes;
133 }
134
135 private char getCurrentCharacter()
136 {
137 return _index < _endIndex ? _constant.charAt(_index) : 0;
138 }
139
140 private void setInvalid()
141 {
142 _valid = false;
143 }
144
145 private boolean endOfTypes()
146 {
147 return _index >= _endIndex || _constant.charAt(_index) == '>';
148 }
149
150 private void parseType(boolean generics)
151 {
152 if (generics)
153 {
154 char currentCharacter = getCurrentCharacter();
155 if (currentCharacter == '+')
156 {
157 _index++;
158 } else if (currentCharacter == '*')
159 {
160 _index++;
161 return;
162 }
163 }
164 boolean arrayType = false;
165 for (; getCurrentCharacter() == '['; _index++)
166 {
167 arrayType = true;
168 }
169 if (arrayType && endOfTypes())
170 {
171 setInvalid();
172 } else
173 {
174 char c = getCurrentCharacter();
175 _index++;
176 if (c == 'L')
177 {
178 parseComplexType();
179 } else if (c == 'T')
180 {
181 int index = _constant.indexOf(';', _index);
182 if (index < 0)
183 {
184 setInvalid();
185 } else
186 {
187 _index = index + 1;
188 }
189 } else if ("BCDFIJSVZ".indexOf(c) < 0)
190 {
191 setInvalid();
192 }
193 }
194 }
195
196 private void parseComplexType()
197 {
198 int typeIndex = _constant.indexOf('<', _index);
199 int endIndex = _constant.indexOf(';', _index);
200 if (typeIndex >= 0 && typeIndex < endIndex) {
201 extractClassName(typeIndex);
202 parseTypes(true);
203 _index += 2;
204 } else if (endIndex > 0)
205 {
206 extractClassName(endIndex);
207 } else
208 {
209 setInvalid();
210 }
211 }
212
213 private void extractClassName(int endIndex)
214 {
215 String className = _constant.substring(_index, endIndex);
216 className = className.replace('/', '.');
217 _classNames.add(className);
218 _index = endIndex + 1;
219 if (isValid(className) == false)
220 {
221 setInvalid();
222 }
223 }
224
225 }
226 |
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