1 /*
2  * Copyright (c) 2007, 2008, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package com.sun.tools.classfile;
27 
28 import java.util.ArrayList;
29 import java.util.List;
30 import com.sun.tools.classfile.Type.*;
31 
32 /**
33  * See JVMS 4.4.4.
34  *
35  *  <p><b>This is NOT part of any supported API.
36  *  If you write code that depends on this, you do so at your own risk.
37  *  This code and its internal interfaces are subject to change or
38  *  deletion without notice.</b>
39  */
40 public class Signature extends Descriptor {
41 
Signature(int index)42     public Signature(int index) {
43         super(index);
44     }
45 
getType(ConstantPool constant_pool)46     public Type getType(ConstantPool constant_pool) throws ConstantPoolException {
47         if (type == null)
48             type = parse(getValue(constant_pool));
49         return type;
50     }
51 
52     @Override
getParameterCount(ConstantPool constant_pool)53     public int getParameterCount(ConstantPool constant_pool) throws ConstantPoolException {
54         MethodType m = (MethodType) getType(constant_pool);
55         return m.paramTypes.size();
56     }
57 
58     @Override
getParameterTypes(ConstantPool constant_pool)59     public String getParameterTypes(ConstantPool constant_pool) throws ConstantPoolException {
60         MethodType m = (MethodType) getType(constant_pool);
61         StringBuilder sb = new StringBuilder();
62         sb.append("(");
63         String sep = "";
64         for (Type paramType: m.paramTypes) {
65             sb.append(sep);
66             sb.append(paramType);
67             sep = ", ";
68         }
69         sb.append(")");
70         return sb.toString();
71     }
72 
73     @Override
getReturnType(ConstantPool constant_pool)74     public String getReturnType(ConstantPool constant_pool) throws ConstantPoolException {
75         MethodType m = (MethodType) getType(constant_pool);
76         return m.returnType.toString();
77     }
78 
79     @Override
getFieldType(ConstantPool constant_pool)80     public String getFieldType(ConstantPool constant_pool) throws ConstantPoolException {
81         return getType(constant_pool).toString();
82     }
83 
parse(String sig)84     private Type parse(String sig) {
85         this.sig = sig;
86         sigp = 0;
87 
88         List<TypeParamType> typeParamTypes = null;
89         if (sig.charAt(sigp) == '<')
90             typeParamTypes = parseTypeParamTypes();
91 
92         if (sig.charAt(sigp) == '(') {
93             List<Type> paramTypes = parseTypeSignatures(')');
94             Type returnType = parseTypeSignature();
95             List<Type> throwsTypes = null;
96             while (sigp < sig.length() && sig.charAt(sigp) == '^') {
97                 sigp++;
98                 if (throwsTypes == null)
99                     throwsTypes = new ArrayList<Type>();
100                 throwsTypes.add(parseTypeSignature());
101             }
102             return new MethodType(typeParamTypes, paramTypes, returnType, throwsTypes);
103         } else {
104             Type t = parseTypeSignature();
105             if (typeParamTypes == null && sigp == sig.length())
106                 return t;
107             Type superclass = t;
108             List<Type> superinterfaces = null;
109             while (sigp < sig.length()) {
110                 if (superinterfaces == null)
111                     superinterfaces = new ArrayList<Type>();
112                 superinterfaces.add(parseTypeSignature());
113             }
114             return new ClassSigType(typeParamTypes, superclass, superinterfaces);
115 
116         }
117     }
118 
parseTypeSignature()119     private Type parseTypeSignature() {
120         switch (sig.charAt(sigp)) {
121             case 'B':
122                 sigp++;
123                 return new SimpleType("byte");
124 
125             case 'C':
126                 sigp++;
127                 return new SimpleType("char");
128 
129             case 'D':
130                 sigp++;
131                 return new SimpleType("double");
132 
133             case 'F':
134                 sigp++;
135                 return new SimpleType("float");
136 
137             case 'I':
138                 sigp++;
139                 return new SimpleType("int");
140 
141             case 'J':
142                 sigp++;
143                 return new SimpleType("long");
144 
145             case 'L':
146                 return parseClassTypeSignature();
147 
148             case 'S':
149                 sigp++;
150                 return new SimpleType("short");
151 
152             case 'T':
153                 return parseTypeVariableSignature();
154 
155             case 'V':
156                 sigp++;
157                 return new SimpleType("void");
158 
159             case 'Z':
160                 sigp++;
161                 return new SimpleType("boolean");
162 
163             case '[':
164                 sigp++;
165                 return new ArrayType(parseTypeSignature());
166 
167             case '*':
168                 sigp++;
169                 return new WildcardType();
170 
171             case '+':
172                 sigp++;
173                 return new WildcardType(WildcardType.Kind.EXTENDS, parseTypeSignature());
174 
175             case '-':
176                 sigp++;
177                 return new WildcardType(WildcardType.Kind.SUPER, parseTypeSignature());
178 
179             default:
180                 throw new IllegalStateException(debugInfo());
181         }
182     }
183 
parseTypeSignatures(char term)184     private List<Type> parseTypeSignatures(char term) {
185         sigp++;
186         List<Type> types = new ArrayList<Type>();
187         while (sig.charAt(sigp) != term)
188             types.add(parseTypeSignature());
189         sigp++;
190         return types;
191     }
192 
parseClassTypeSignature()193     private Type parseClassTypeSignature() {
194         assert sig.charAt(sigp) == 'L';
195         sigp++;
196         return parseClassTypeSignatureRest();
197     }
198 
parseClassTypeSignatureRest()199     private Type parseClassTypeSignatureRest() {
200         StringBuilder sb = new StringBuilder();
201         List<Type> argTypes = null;
202         ClassType t = null;
203         char sigch ;
204 
205         do {
206             switch  (sigch = sig.charAt(sigp)) {
207                 case '<':
208                     argTypes = parseTypeSignatures('>');
209                     break;
210 
211                 case '.':
212                 case ';':
213                     sigp++;
214                     t = new ClassType(t, sb.toString(), argTypes);
215                     sb.setLength(0);
216                     argTypes = null;
217                     break;
218 
219                 default:
220                     sigp++;
221                     sb.append(sigch);
222                     break;
223             }
224         } while (sigch != ';');
225 
226         return t;
227     }
228 
parseTypeParamTypes()229     private List<TypeParamType> parseTypeParamTypes() {
230         assert sig.charAt(sigp) == '<';
231         sigp++;
232         List<TypeParamType> types = new ArrayList<TypeParamType>();
233         while (sig.charAt(sigp) != '>')
234             types.add(parseTypeParamType());
235         sigp++;
236         return types;
237     }
238 
parseTypeParamType()239     private TypeParamType parseTypeParamType() {
240         int sep = sig.indexOf(":", sigp);
241         String name = sig.substring(sigp, sep);
242         Type classBound = null;
243         List<Type> interfaceBounds = null;
244         sigp = sep + 1;
245         if (sig.charAt(sigp) != ':')
246             classBound = parseTypeSignature();
247         while (sig.charAt(sigp) == ':') {
248             sigp++;
249             if (interfaceBounds == null)
250                 interfaceBounds = new ArrayList<Type>();
251             interfaceBounds.add(parseTypeSignature());
252         }
253         return new TypeParamType(name, classBound, interfaceBounds);
254     }
255 
parseTypeVariableSignature()256     private Type parseTypeVariableSignature() {
257         sigp++;
258         int sep = sig.indexOf(';', sigp);
259         Type t = new SimpleType(sig.substring(sigp, sep));
260         sigp = sep + 1;
261         return t;
262     }
263 
debugInfo()264     private String debugInfo() {
265         return sig.substring(0, sigp) + "!" + sig.charAt(sigp) + "!" + sig.substring(sigp+1);
266     }
267 
268     private String sig;
269     private int sigp;
270 
271     private Type type;
272 }
273