Source for gnu.java.lang.ClassHelper

   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: }