gomp-20050608-branch/libjava/classpath/gnu/java/lang/ClassHelper.java

   1 /* ClassHelper.java -- Utility methods to augment java.lang.Class
   2    Copyright (C) 1998, 2002 Free Software Foundation, Inc.
   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 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package gnu.java.lang;
  40
  41 import java.lang.reflect.Field;
  42 import java.lang.reflect.Method;
  43 import java.util.Arrays;
  44 import java.util.HashMap;
  45 import java.util.HashSet;
  46 import java.util.Iterator;
  47 import java.util.Map;
  48 import java.util.Set;
  49
  50 /**
  51  * ClassHelper has various methods that ought to have been in Class.
  52  *
  53  * @author John Keiser
  54  * @author Eric Blake (ebb9@email.byu.edu)
  55  */
  56 public class ClassHelper
  57 {
  58   /**
  59    * Strip the package part from the class name.
  60    *
  61    * @param clazz the class to get the truncated name from
  62    * @return the truncated class name
  63    */
  64   public static String getTruncatedClassName(Class clazz)
  65   {
  66     return getTruncatedName(clazz.getName());
  67   }
  68
  69   /**
  70    * Strip the package part from the class name, or the class part from
  71    * the method or field name.
  72    *
  73    * @param name the name to truncate
  74    * @return the truncated name
  75    */
  76   public static String getTruncatedName(String name)
  77   {
  78     int lastInd = name.lastIndexOf('.');
  79     if (lastInd == -1)
  80       return name;
  81     return name.substring(lastInd + 1);
  82   }
  83
  84   /** Cache of methods found in getAllMethods(). */
  85   private static Map allMethods = new HashMap();
  86
  87   /**
  88    * Get all the methods, public, private and otherwise, from the class,
  89    * getting them from the most recent class to find them. This may not
  90    * be quite the correct approach, as this includes methods that are not
  91    * inherited or accessible from clazz, so beware.
  92    *
  93    * @param clazz the class to start at
  94    * @return all methods declared or inherited in clazz
  95    */
  96   public static Method[] getAllMethods(Class clazz)
  97   {
  98     Method[] retval = (Method[]) allMethods.get(clazz);
  99     if (retval == null)
 100       {
 101         Set methods = new HashSet();
 102         Class c = clazz;
 103         while (c != null)
 104           {
 105             Method[] currentMethods = c.getDeclaredMethods();
 106           loop:
 107             for (int i = 0; i < currentMethods.length; i++)
 108               {
 109                 Method current = currentMethods[i];
 110                 int size = methods.size();
 111                 Iterator iter = methods.iterator();
 112                 while (--size >= 0)
 113                   {
 114                     Method override = (Method) iter.next();
 115                     if (current.getName().equals(override.getName())
 116                         && Arrays.equals(current.getParameterTypes(),
 117                                          override.getParameterTypes())
 118                         && current.getReturnType() == override.getReturnType())
 119                       continue loop;
 120                   }
 121                 methods.add(current);
 122               }
 123             c = c.getSuperclass();
 124           }
 125         retval = new Method[methods.size()];
 126         methods.toArray(retval);
 127         allMethods.put(clazz, retval);
 128       }
 129     return retval;
 130   }
 131
 132   /** Cache of fields found in getAllFields(). */
 133   private static Map allFields = new HashMap();
 134
 135   /**
 136    * Get all the fields, public, private and otherwise, from the class,
 137    * getting them from the most recent class to find them. This may not
 138    * be quite the correct approach, as this includes fields that are not
 139    * inherited or accessible from clazz, so beware.
 140    *
 141    * @param clazz the class to start at
 142    * @return all fields declared or inherited in clazz
 143    */
 144   public static Field[] getAllFields(Class clazz)
 145   {
 146     Field[] retval = (Field[]) allFields.get(clazz);
 147     if (retval == null)
 148       {
 149         Set fields = new HashSet();
 150         Class c = clazz;
 151         while (c != null)
 152           {
 153             Field[] currentFields = c.getDeclaredFields();
 154           loop:
 155             for (int i = 0; i < currentFields.length; i++)
 156               {
 157                 Field current = currentFields[i];
 158                 int size = fields.size();
 159                 Iterator iter = fields.iterator();
 160                 while (--size >= 0)
 161                   {
 162                     Field override = (Field) iter.next();
 163                     if (current.getName().equals(override.getName())
 164                         && current.getType() == override.getType())
 165                       continue loop;
 166                   }
 167                 fields.add(current);
 168               }
 169             c = c.getSuperclass();
 170           }
 171         retval = new Field[fields.size()];
 172         fields.toArray(retval);
 173         allFields.put(clazz, retval);
 174       }
 175     return retval;
 176   }
 177 }