1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
|
/*
* ProGuard -- shrinking, optimization, obfuscation, and preverification
* of Java bytecode.
*
* Copyright (c) 2002-2017 Eric Lafortune @ GuardSquare
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package proguard.classfile.util;
import proguard.classfile.ClassConstants;
/**
* An <code>InternalTypeEnumeration</code> provides an enumeration of all
* types listed in a given internal descriptor or signature of a class, a
* method, or a field.
*
* The leading formal type parameters, if any, can be retrieved separately.
*
* The return type of a method descriptor can also be retrieved separately.
*
* @author Eric Lafortune
*/
public class InternalTypeEnumeration
{
private String descriptor;
private int formalTypeParametersIndex;
private int openIndex;
private int closeIndex;
private int index;
/**
* Creates a new InternalTypeEnumeration for the given method descriptor.
*/
public InternalTypeEnumeration(String descriptor)
{
this.descriptor = descriptor;
// Find any formal type parameters.
if (descriptor.charAt(0) == ClassConstants.TYPE_GENERIC_START)
{
formalTypeParametersIndex = 1;
int nestingLevel = 1;
do
{
char c = descriptor.charAt(formalTypeParametersIndex++);
switch (c)
{
case ClassConstants.TYPE_GENERIC_START:
{
nestingLevel++;
break;
}
case ClassConstants.TYPE_GENERIC_END:
{
nestingLevel--;
break;
}
}
}
while (nestingLevel > 0);
}
this.openIndex = descriptor.indexOf(ClassConstants.METHOD_ARGUMENTS_OPEN,
formalTypeParametersIndex);
this.closeIndex = openIndex >= 0 ?
descriptor.indexOf(ClassConstants.METHOD_ARGUMENTS_CLOSE, openIndex) :
descriptor.length();
this.index = openIndex >= 0 ?
openIndex + 1 :
formalTypeParametersIndex;
}
/**
* Returns whether the descriptor has leading formal type parameters.
*/
public boolean hasFormalTypeParameters()
{
return formalTypeParametersIndex > 0;
}
/**
* Returns the leading formal type parameters from the descriptor.
*/
public String formalTypeParameters()
{
return descriptor.substring(0, formalTypeParametersIndex);
}
/**
* Returns whether the descriptor is a method signature.
*/
public boolean isMethodSignature()
{
return openIndex >= 0;
}
/**
* Returns whether the enumeration can provide more types from the method
* descriptor.
*/
public boolean hasMoreTypes()
{
return index < closeIndex;
}
/**
* Returns the next type from the method descriptor.
*/
public String nextType()
{
int startIndex = index;
skipArray();
char c = descriptor.charAt(index++);
switch (c)
{
case ClassConstants.TYPE_CLASS_START:
case ClassConstants.TYPE_GENERIC_VARIABLE_START:
{
skipClass();
break;
}
case ClassConstants.TYPE_GENERIC_START:
{
skipGeneric();
break;
}
}
return descriptor.substring(startIndex, index);
}
/**
* Returns the return type from the descriptor, assuming it's a method
* descriptor.
*/
public String returnType()
{
return descriptor.substring(closeIndex + 1);
}
// Small utility methods.
private void skipArray()
{
while (descriptor.charAt(index) == ClassConstants.TYPE_ARRAY)
{
index++;
}
}
private void skipClass()
{
while (true)
{
char c = descriptor.charAt(index++);
switch (c)
{
case ClassConstants.TYPE_GENERIC_START:
skipGeneric();
break;
case ClassConstants.TYPE_CLASS_END:
return;
}
}
}
private void skipGeneric()
{
int nestingLevel = 1;
do
{
char c = descriptor.charAt(index++);
switch (c)
{
case ClassConstants.TYPE_GENERIC_START:
nestingLevel++;
break;
case ClassConstants.TYPE_GENERIC_END:
nestingLevel--;
break;
}
}
while (nestingLevel > 0);
}
/**
* A main method for testing the type enumeration.
*/
public static void main(String[] args)
{
try
{
for (int index = 0; index < args.length; index++)
{
String descriptor = args[index];
System.out.println("Descriptor ["+descriptor+"]");
InternalTypeEnumeration enumeration = new InternalTypeEnumeration(descriptor);
if (enumeration.hasFormalTypeParameters())
{
System.out.println(" Formal type parameters ["+enumeration.formalTypeParameters()+"]");
}
while (enumeration.hasMoreTypes())
{
System.out.println(" Type ["+enumeration.nextType()+"]");
}
if (enumeration.isMethodSignature())
{
System.out.println(" Return type ["+enumeration.returnType()+"]");
}
}
}
catch (Exception ex)
{
ex.printStackTrace();
}
}
}
|
