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 
  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      */
  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      */
  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 
  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      */
  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 (loader == null)
  94                     ? Class.forName(name, false, null)
  95                     : loader.loadClass(name);
  96             } catch (ClassNotFoundException ex) {
  97                 throw new TypeNotPresentException(name, ex);
  98             }
  99         } else if (c == '[') {
 100             Class<?> t = parseSig(str, i, end, loader);
 101             if (t != null)
 102                 t = java.lang.reflect.Array.newInstance(t, 0).getClass();
 103             return t;
 104         } else {
 105             return Wrapper.forBasicType(c).primitiveType();
 106         }
 107     }
 108 
 109     public static String unparse(Class<?> type) {
 110         StringBuilder sb = new StringBuilder();
 111         unparseSig(type, sb);
 112         return sb.toString();
 113     }
 114 
 115     public static String unparse(MethodType type) {
 116         return unparseMethod(type.returnType(), type.parameterArray());
 117     }
 118 
 119     public static String unparse(Object type) {
 120         if (type instanceof Class<?>)
 121             return unparse((Class<?>) type);
 122         if (type instanceof MethodType)
 123             return unparse((MethodType) type);
 124         return (String) type;
 125     }
 126 
 127     public static String unparseMethod(Class<?> rtype, List<Class<?>> ptypes) {
 128         StringBuilder sb = new StringBuilder();
 129         sb.append('(');
 130         for (Class<?> pt : ptypes)
 131             unparseSig(pt, sb);
 132         sb.append(')');
 133         unparseSig(rtype, sb);
 134         return sb.toString();
 135     }
 136 
 137     public static String unparseMethod(Class<?> rtype, Class<?>[] ptypes) {
 138         StringBuilder sb = new StringBuilder();
 139         sb.append('(');
 140         for (Class<?> pt : ptypes)
 141             unparseSig(pt, sb);
 142         sb.append(')');
 143         unparseSig(rtype, sb);
 144         return sb.toString();
 145     }
 146 
 147     private static void unparseSig(Class<?> t, StringBuilder sb) {
 148         char c = Wrapper.forBasicType(t).basicTypeChar();
 149         if (c != 'L') {
 150             sb.append(c);
 151         } else {
 152             boolean lsemi = (!t.isArray());
 153             if (lsemi)  sb.append('L');
 154             sb.append(t.getName().replace('.', '/'));
 155             if (lsemi)  sb.append(';');
 156         }
 157     }
 158 
 159 }