Source for gnu.classpath.jdwp.util.Signature

   1: /* Signature.java -- utility class to compute class and method signatures
   2:    Copyright (C) 2005 Free Software Foundation
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: terms of your choice, provided that you also meet, for each linked
  32: independent module, the terms and conditions of the license of that
  33: module.  An independent module is a module which is not derived from
  34: or based on this library.  If you modify this library, you may extend
  35: this exception to your version of the library, but you are not
  36: obligated to do so.  If you do not wish to do so, delete this
  37: exception statement from your version. */
  38: 
  39: 
  40: package gnu.classpath.jdwp.util;
  41: 
  42: import gnu.java.lang.CPStringBuilder;
  43: 
  44: import java.lang.reflect.Field;
  45: import java.lang.reflect.Method;
  46: 
  47: /**
  48:  * A class to compute class and method signatures.
  49:  *
  50:  * @author Tom Tromey  (tromey@redhat.com)
  51:  * @author Keith Seitz  (keiths@redhat.com)
  52:  */
  53: public class Signature
  54: {
  55:   /**
  56:    * Computes the class signature, i.e., java.lang.String.class
  57:    * returns "Ljava/lang/String;".
  58:    *
  59:    * @param theClass  the class for which to compute the signature
  60:    * @return          the class's type signature
  61:    */
  62:   public static String computeClassSignature (Class theClass)
  63:   {
  64:     CPStringBuilder sb = new CPStringBuilder ();
  65:     _addToSignature (sb, theClass);
  66:     return sb.toString ();
  67:   }
  68: 
  69:   /**
  70:    * Computes the field signature which is just the class signature of the
  71:    * field's type, ie a Field of type java.lang.String this will return
  72:    * "Ljava/lang/String;".
  73:    *
  74:    * @param field  the field for which to compute the signature
  75:    * @return       the field's type signature
  76:    */
  77:   public static String computeFieldSignature (Field field)
  78:   {
  79:     return computeClassSignature (field.getType());
  80:   }
  81: 
  82:   /**
  83:    * Computes the method signature, i.e., java.lang.String.split (String, int)
  84:    * returns "(Ljava/lang/String;I)[Ljava/lang/String;"
  85:    *
  86:    * @param method  the method for which to compute the signature
  87:    * @return        the method's type signature
  88:    */
  89:   public static String computeMethodSignature (Method method)
  90:   {
  91:     return _computeSignature (method.getReturnType (),
  92:                               method.getParameterTypes ());
  93:   }
  94: 
  95:   private static String _computeSignature (Class returnType,
  96:                                            Class[] paramTypes)
  97:   {
  98:     CPStringBuilder sb = new CPStringBuilder ("(");
  99:     if (paramTypes != null)
 100:       {
 101:         for (int i = 0; i < paramTypes.length; ++i)
 102:           _addToSignature (sb, paramTypes[i]);
 103:       }
 104:     sb.append (")");
 105:     _addToSignature (sb, returnType);
 106:     return sb.toString();
 107:   }
 108: 
 109:   private static void _addToSignature (CPStringBuilder sb, Class k)
 110:   {
 111:     // For some reason there's no easy way to get the signature of a
 112:     // class.
 113:     if (k.isPrimitive ())
 114:       {
 115:         if (k == void.class)
 116:           sb.append('V');
 117:         else if (k == boolean.class)
 118:           sb.append('Z');
 119:         else if (k == byte.class)
 120:           sb.append('B');
 121:         else if (k == char.class)
 122:           sb.append('C');
 123:         else if (k == short.class)
 124:           sb.append('S');
 125:         else if (k == int.class)
 126:           sb.append('I');
 127:         else if (k == float.class)
 128:           sb.append('F');
 129:         else if (k == double.class)
 130:           sb.append('D');
 131:         else if (k == long.class)
 132:           sb.append('J');
 133:         return;
 134:       }
 135: 
 136:     String name = k.getName ();
 137:     int len = name.length ();
 138:     sb.ensureCapacity (len);
 139:     if (! k.isArray ())
 140:       sb.append('L');
 141:     for (int i = 0; i < len; ++i)
 142:       {
 143:         char c = name.charAt (i);
 144:         if (c == '.')
 145:           c = '/';
 146:         sb.append (c);
 147:       }
 148:     if (! k.isArray ())
 149:       sb.append(';');
 150:   }
 151: }