Thu, 12 Jan 2012 15:28:34 +0000
7123100: javac fails with java.lang.StackOverflowError
Summary: Inference of under-constrained type-variables creates erroneous recursive wildcard types
Reviewed-by: jjg
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 */
26 package com.sun.tools.classfile;
28 import java.util.ArrayList;
29 import java.util.List;
30 import com.sun.tools.classfile.Type.*;
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 {
42 public Signature(int index) {
43 super(index);
44 }
46 public Type getType(ConstantPool constant_pool) throws ConstantPoolException {
47 if (type == null)
48 type = parse(getValue(constant_pool));
49 return type;
50 }
52 @Override
53 public int getParameterCount(ConstantPool constant_pool) throws ConstantPoolException {
54 MethodType m = (MethodType) getType(constant_pool);
55 return m.paramTypes.size();
56 }
58 @Override
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 }
73 @Override
74 public String getReturnType(ConstantPool constant_pool) throws ConstantPoolException {
75 MethodType m = (MethodType) getType(constant_pool);
76 return m.returnType.toString();
77 }
79 @Override
80 public String getFieldType(ConstantPool constant_pool) throws ConstantPoolException {
81 return getType(constant_pool).toString();
82 }
84 private Type parse(String sig) {
85 this.sig = sig;
86 sigp = 0;
88 List<TypeParamType> typeParamTypes = null;
89 if (sig.charAt(sigp) == '<')
90 typeParamTypes = parseTypeParamTypes();
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);
116 }
117 }
119 private Type parseTypeSignature() {
120 switch (sig.charAt(sigp)) {
121 case 'B':
122 sigp++;
123 return new SimpleType("byte");
125 case 'C':
126 sigp++;
127 return new SimpleType("char");
129 case 'D':
130 sigp++;
131 return new SimpleType("double");
133 case 'F':
134 sigp++;
135 return new SimpleType("float");
137 case 'I':
138 sigp++;
139 return new SimpleType("int");
141 case 'J':
142 sigp++;
143 return new SimpleType("long");
145 case 'L':
146 return parseClassTypeSignature();
148 case 'S':
149 sigp++;
150 return new SimpleType("short");
152 case 'T':
153 return parseTypeVariableSignature();
155 case 'V':
156 sigp++;
157 return new SimpleType("void");
159 case 'Z':
160 sigp++;
161 return new SimpleType("boolean");
163 case '[':
164 sigp++;
165 return new ArrayType(parseTypeSignature());
167 case '*':
168 sigp++;
169 return new WildcardType();
171 case '+':
172 sigp++;
173 return new WildcardType(WildcardType.Kind.EXTENDS, parseTypeSignature());
175 case '-':
176 sigp++;
177 return new WildcardType(WildcardType.Kind.SUPER, parseTypeSignature());
179 default:
180 throw new IllegalStateException(debugInfo());
181 }
182 }
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 }
193 private Type parseClassTypeSignature() {
194 assert sig.charAt(sigp) == 'L';
195 sigp++;
196 return parseClassTypeSignatureRest();
197 }
199 private Type parseClassTypeSignatureRest() {
200 StringBuilder sb = new StringBuilder();
201 List<Type> argTypes = null;
202 ClassType t = null;
203 char sigch ;
205 do {
206 switch (sigch = sig.charAt(sigp)) {
207 case '<':
208 argTypes = parseTypeSignatures('>');
209 break;
211 case '.':
212 case ';':
213 sigp++;
214 t = new ClassType(t, sb.toString(), argTypes);
215 sb.setLength(0);
216 argTypes = null;
217 break;
219 default:
220 sigp++;
221 sb.append(sigch);
222 break;
223 }
224 } while (sigch != ';');
226 return t;
227 }
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 }
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 }
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 }
264 private String debugInfo() {
265 return sig.substring(0, sigp) + "!" + sig.charAt(sigp) + "!" + sig.substring(sigp+1);
266 }
268 private String sig;
269 private int sigp;
271 private Type type;
272 }