1 /*
2  * Copyright (c) 2008, 2015, 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 sun.invoke.util;
27 
28 import java.lang.invoke.MethodType;
29 import java.util.ArrayList;
30 import java.util.List;
31 
32 /**
33  * Utility routines for dealing with bytecode-level signatures.
34  * @author jrose
35  */
36 public class BytecodeDescriptor {
37 
BytecodeDescriptor()38     private BytecodeDescriptor() { }  // cannot instantiate
39 
40     /**
41      * @param loader the class loader in which to look up the types (null means
42      *               bootstrap class loader)
43      */
parseMethod(String bytecodeSignature, ClassLoader loader)44     public static List<Class<?>> parseMethod(String bytecodeSignature, ClassLoader loader) {
45         return parseMethod(bytecodeSignature, 0, bytecodeSignature.length(), loader);
46     }
47 
48     /**
49      * @param loader the class loader in which to look up the types (null means
50      *               bootstrap class loader)
51      */
parseMethod(String bytecodeSignature, int start, int end, ClassLoader loader)52     static List<Class<?>> parseMethod(String bytecodeSignature,
53             int start, int end, ClassLoader loader) {
54         String str = bytecodeSignature;
55         int[] i = {start};
56         ArrayList<Class<?>> ptypes = new ArrayList<Class<?>>();
57         if (i[0] < end && str.charAt(i[0]) == '(') {
58             ++i[0];  // skip '('
59             while (i[0] < end && str.charAt(i[0]) != ')') {
60                 Class<?> pt = parseSig(str, i, end, loader);
61                 if (pt == null || pt == void.class)
62                     parseError(str, "bad argument type");
63                 ptypes.add(pt);
64             }
65             ++i[0];  // skip ')'
66         } else {
67             parseError(str, "not a method type");
68         }
69         Class<?> rtype = parseSig(str, i, end, loader);
70         if (rtype == null || i[0] != end)
71             parseError(str, "bad return type");
72         ptypes.add(rtype);
73         return ptypes;
74     }
75 
parseError(String str, String msg)76     private static void parseError(String str, String msg) {
77         throw new IllegalArgumentException("bad signature: "+str+": "+msg);
78     }
79 
80     /**
81      * @param loader the class loader in which to look up the types (null means
82      *               bootstrap class loader)
83      */
parseSig(String str, int[] i, int end, ClassLoader loader)84     private static Class<?> parseSig(String str, int[] i, int end, ClassLoader loader) {
85         if (i[0] == end)  return null;
86         char c = str.charAt(i[0]++);
87         if (c == 'L') {
88             int begc = i[0], endc = str.indexOf(';', begc);
89             if (endc < 0)  return null;
90             i[0] = endc+1;
91             String name = str.substring(begc, endc).replace('/', '.');
92             try {
93                 return Class.forName(name, false, loader);
94             } catch (ClassNotFoundException ex) {
95                 throw new TypeNotPresentException(name, ex);
96             }
97         } else if (c == '[') {
98             Class<?> t = parseSig(str, i, end, loader);
99             if (t != null)
100                 t = java.lang.reflect.Array.newInstance(t, 0).getClass();
101             return t;
102         } else {
103             return Wrapper.forBasicType(c).primitiveType();
104         }
105     }
106 
unparse(Class<?> type)107     public static String unparse(Class<?> type) {
108         if (type == Object.class) {
109             return "Ljava/lang/Object;";
110         } else if (type == int.class) {
111             return "I";
112         }
113         return type.descriptorString();
114     }
115 
unparse(MethodType type)116     public static String unparse(MethodType type) {
117         return unparseMethod(type.returnType(), type.parameterArray());
118     }
119 
unparse(Object type)120     public static String unparse(Object type) {
121         if (type instanceof Class<?>)
122             return unparse((Class<?>) type);
123         if (type instanceof MethodType)
124             return unparse((MethodType) type);
125         return (String) type;
126     }
127 
unparseMethod(Class<?> rtype, List<Class<?>> ptypes)128     public static String unparseMethod(Class<?> rtype, List<Class<?>> ptypes) {
129         StringBuilder sb = new StringBuilder();
130         sb.append('(');
131         for (Class<?> pt : ptypes)
132             unparseSig(pt, sb);
133         sb.append(')');
134         unparseSig(rtype, sb);
135         return sb.toString();
136     }
137 
unparseMethod(Class<?> rtype, Class<?>[] ptypes)138     public static String unparseMethod(Class<?> rtype, Class<?>[] ptypes) {
139         StringBuilder sb = new StringBuilder();
140         sb.append('(');
141         for (Class<?> pt : ptypes)
142             unparseSig(pt, sb);
143         sb.append(')');
144         unparseSig(rtype, sb);
145         return sb.toString();
146     }
147 
unparseSig(Class<?> t, StringBuilder sb)148     private static void unparseSig(Class<?> t, StringBuilder sb) {
149         char c = Wrapper.forBasicType(t).basicTypeChar();
150         if (c != 'L') {
151             sb.append(c);
152         } else if (t == Object.class) {
153             sb.append("Ljava/lang/Object;");
154         } else {
155             sb.append(t.descriptorString());
156         }
157     }
158 }
159