libjava/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., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 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.util.*;
  42 import java.lang.reflect.*;
  43
  44 /**
  45  * ClassHelper has various methods that ought to have been in Class.
  46  *
  47  * @author John Keiser
  48  * @author Eric Blake <ebb9@email.byu.edu>
  49  */
  50 public class ClassHelper
  51 {
  52   /**
  53    * Strip the package part from the class name.
  54    *
  55    * @param clazz the class to get the truncated name from
  56    * @return the truncated class name
  57    */
  58   public static String getTruncatedClassName(Class clazz)
  59   {
  60     return getTruncatedName(clazz.getName());
  61   }
  62
  63   /**
  64    * Strip the package part from the class name, or the class part from
  65    * the method or field name.
  66    *
  67    * @param name the name to truncate
  68    * @return the truncated name
  69    */
  70   public static String getTruncatedName(String name)
  71   {
  72     int lastInd = name.lastIndexOf('.');
  73     if (lastInd == -1)
  74       return name;
  75     return name.substring(lastInd + 1);
  76   }
  77
  78   /**
  79    * Strip the last portion of the name (after the last dot).
  80    *
  81    * @param name the name to get package of
  82    * @return the package name, or "" if no package
  83    */
  84   public static String getPackagePortion(String name)
  85   {
  86     int lastInd = name.lastIndexOf('.');
  87     if (lastInd == -1)
  88       return "";
  89     return name.substring(0, lastInd);
  90   }
  91
  92   /** Cache of methods found in getAllMethods(). */
  93   private static Map allMethods = new HashMap();
  94
  95   /**
  96    * Get all the methods, public, private and otherwise, from the class,
  97    * getting them from the most recent class to find them. This may not
  98    * be quite the correct approach, as this includes methods that are not
  99    * inherited or accessible from clazz, so beware.
 100    *
 101    * @param clazz the class to start at
 102    * @return all methods declared or inherited in clazz
 103    */
 104   public static Method[] getAllMethods(Class clazz)
 105   {
 106     Method[] retval = (Method[]) allMethods.get(clazz);
 107     if (retval == null)
 108       {
 109         Set methods = new HashSet();
 110         Class c = clazz;
 111         while (c != null)
 112           {
 113             Method[] currentMethods = c.getDeclaredMethods();
 114           loop:
 115             for (int i = 0; i < currentMethods.length; i++)
 116               {
 117                 Method current = currentMethods[i];
 118                 int size = methods.size();
 119                 Iterator iter = methods.iterator();
 120                 while (--size >= 0)
 121                   {
 122                     Method override = (Method) iter.next();
 123                     if (current.getName().equals(override.getName())
 124                         && Arrays.equals(current.getParameterTypes(),
 125                                          override.getParameterTypes())
 126                         && current.getReturnType() == override.getReturnType())
 127                       continue loop;
 128                   }
 129                 methods.add(current);
 130               }
 131             c = c.getSuperclass();
 132           }
 133         retval = new Method[methods.size()];
 134         methods.toArray(retval);
 135         allMethods.put(clazz, retval);
 136       }
 137     return retval;
 138   }
 139
 140   /** Cache of fields found in getAllFields(). */
 141   private static Map allFields = new HashMap();
 142
 143   /**
 144    * Get all the fields, public, private and otherwise, from the class,
 145    * getting them from the most recent class to find them. This may not
 146    * be quite the correct approach, as this includes fields that are not
 147    * inherited or accessible from clazz, so beware.
 148    *
 149    * @param clazz the class to start at
 150    * @return all fields declared or inherited in clazz
 151    */
 152   public static Field[] getAllFields(Class clazz)
 153   {
 154     Field[] retval = (Field[]) allFields.get(clazz);
 155     if (retval == null)
 156       {
 157         Set fields = new HashSet();
 158         Class c = clazz;
 159         while (c != null)
 160           {
 161             Field[] currentFields = c.getDeclaredFields();
 162           loop:
 163             for (int i = 0; i < currentFields.length; i++)
 164               {
 165                 Field current = currentFields[i];
 166                 int size = fields.size();
 167                 Iterator iter = fields.iterator();
 168                 while (--size >= 0)
 169                   {
 170                     Field override = (Field) iter.next();
 171                     if (current.getName().equals(override.getName())
 172                         && current.getType() == override.getType())
 173                       continue loop;
 174                   }
 175                 fields.add(current);
 176               }
 177             c = c.getSuperclass();
 178           }
 179         retval = new Field[fields.size()];
 180         fields.toArray(retval);
 181         allFields.put(clazz, retval);
 182       }
 183     return retval;
 184   }
 185 }