Home | History | Annotate | Download | only in util 
      1 /*
      2  * Copyright (c) 2008, 2011, 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     public static List<Class<?>> parseMethod(String bytecodeSignature, ClassLoader loader) {
     41         return parseMethod(bytecodeSignature, 0, bytecodeSignature.length(), loader);
     42     }
     43 
     44     static List<Class<?>> parseMethod(String bytecodeSignature,
     45             int start, int end, ClassLoader loader) {
     46         if (loader == null)
     47             loader = ClassLoader.getSystemClassLoader();
     48         String str = bytecodeSignature;
     49         int[] i = {start};
     50         ArrayList<Class<?>> ptypes = new ArrayList<Class<?>>();
     51         if (i[0] < end && str.charAt(i[0]) == '(') {
     52             ++i[0];  // skip '('
     53             while (i[0] < end && str.charAt(i[0]) != ')') {
     54                 Class<?> pt = parseSig(str, i, end, loader);
     55                 if (pt == null || pt == void.class)
     56                     parseError(str, "bad argument type");
     57                 ptypes.add(pt);
     58             }
     59             ++i[0];  // skip ')'
     60         } else {
     61             parseError(str, "not a method type");
     62         }
     63         Class<?> rtype = parseSig(str, i, end, loader);
     64         if (rtype == null || i[0] != end)
     65             parseError(str, "bad return type");
     66         ptypes.add(rtype);
     67         return ptypes;
     68     }
     69 
     70     static private void parseError(String str, String msg) {
     71         throw new IllegalArgumentException("bad signature: "+str+": "+msg);
     72     }
     73 
     74     static private Class<?> parseSig(String str, int[] i, int end, ClassLoader loader) {
     75         if (i[0] == end)  return null;
     76         char c = str.charAt(i[0]++);
     77         if (c == 'L') {
     78             int begc = i[0], endc = str.indexOf(';', begc);
     79             if (endc < 0)  return null;
     80             i[0] = endc+1;
     81             String name = str.substring(begc, endc).replace('/', '.');
     82             try {
     83                 return loader.loadClass(name);
     84             } catch (ClassNotFoundException ex) {
     85                 throw new TypeNotPresentException(name, ex);
     86             }
     87         } else if (c == '[') {
     88             Class<?> t = parseSig(str, i, end, loader);
     89             if (t != null)
     90                 t = java.lang.reflect.Array.newInstance(t, 0).getClass();
     91             return t;
     92         } else {
     93             return Wrapper.forBasicType(c).primitiveType();
     94         }
     95     }
     96 
     97     public static String unparse(Class<?> type) {
     98         StringBuilder sb = new StringBuilder();
     99         unparseSig(type, sb);
    100         return sb.toString();
    101     }
    102 
    103     public static String unparse(MethodType type) {
    104         return unparseMethod(type.returnType(), type.parameterList());
    105     }
    106 
    107     public static String unparse(Object type) {
    108         if (type instanceof Class<?>)
    109             return unparse((Class<?>) type);
    110         if (type instanceof MethodType)
    111             return unparse((MethodType) type);
    112         return (String) type;
    113     }
    114 
    115     public static String unparseMethod(Class<?> rtype, List<Class<?>> ptypes) {
    116         StringBuilder sb = new StringBuilder();
    117         sb.append('(');
    118         for (Class<?> pt : ptypes)
    119             unparseSig(pt, sb);
    120         sb.append(')');
    121         unparseSig(rtype, sb);
    122         return sb.toString();
    123     }
    124 
    125     static private void unparseSig(Class<?> t, StringBuilder sb) {
    126         char c = Wrapper.forBasicType(t).basicTypeChar();
    127         if (c != 'L') {
    128             sb.append(c);
    129         } else {
    130             boolean lsemi = (!t.isArray());
    131             if (lsemi)  sb.append('L');
    132             sb.append(t.getName().replace('.', '/'));
    133             if (lsemi)  sb.append(';');
    134         }
    135     }
    136 
    137 }
    138