libjava/java/beans/PropertyEditorManager.java

   1 /* java.beans.PropertyEditorManager
   2    Copyright (C) 1998 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 java.beans;
  40
  41 import gnu.java.lang.ClassHelper;
  42
  43 /**
  44  ** PropertyEditorManager is used to find property editors
  45  ** for various types (not necessarily Beans).<P>
  46  **
  47  ** It first checks to see if the property editor is
  48  ** already registered; if it is, that property editor is
  49  ** used.  Next it takes the type's classname and appends
  50  ** "Editor" to it, and searches first in the class's
  51  ** package and then in the property editor search path.<P>
  52  **
  53  ** Default property editors are provided for:<P>
  54  ** <OL>
  55  ** <LI>boolean, byte, short, int, long, float, and double</LI>
  56  ** <LI>java.lang.String</LI>
  57  ** <LI>java.awt.Color</LI>
  58  ** <LI>java.awt.Font</LI>
  59  ** <OL>
  60  **
  61  ** <STRONG>Spec Suggestion:</STRONG> Perhaps an editor for
  62  ** Filename or something like it should be provided.  As well
  63  ** as char.
  64  **
  65  ** @author John Keiser
  66  ** @since JDK1.1
  67  ** @version 1.1.0, 29 Jul 1998
  68  **/
  69
  70 public class PropertyEditorManager {
  71         static java.util.Hashtable editors = new java.util.Hashtable();
  72         static String[] editorSearchPath = {"gnu.java.beans.editors","sun.beans.editors"};
  73
  74         static {
  75                 registerEditor(java.lang.Boolean.TYPE, gnu.java.beans.editors.NativeBooleanEditor.class);
  76                 registerEditor(java.lang.Byte.TYPE,    gnu.java.beans.editors.NativeByteEditor.class);
  77                 registerEditor(java.lang.Short.TYPE,   gnu.java.beans.editors.NativeShortEditor.class);
  78                 registerEditor(java.lang.Integer.TYPE, gnu.java.beans.editors.NativeIntEditor.class);
  79                 registerEditor(java.lang.Long.TYPE,    gnu.java.beans.editors.NativeLongEditor.class);
  80                 registerEditor(java.lang.Float.TYPE,   gnu.java.beans.editors.NativeFloatEditor.class);
  81                 registerEditor(java.lang.Double.TYPE,  gnu.java.beans.editors.NativeDoubleEditor.class);
  82                 registerEditor(java.lang.String.class, gnu.java.beans.editors.StringEditor.class);
  83                 registerEditor(java.awt.Color.class,   gnu.java.beans.editors.ColorEditor.class);
  84                 registerEditor(java.awt.Font.class,    gnu.java.beans.editors.FontEditor.class);
  85         }
  86
  87         /** Beats me why this class can be instantiated, but there
  88          ** you have it.
  89          **/
  90         public PropertyEditorManager() { }
  91
  92         /** Register an editor for a class.  Replaces old editor
  93          ** if there was one registered before.
  94          ** @param editedClass the class that the property editor
  95          **        will edit.
  96          ** @param editorClass the PropertyEditor class.
  97          **/
  98         public static void registerEditor(Class editedClass, Class editorClass) {
  99                 editors.put(editedClass, editorClass);
 100         }
 101
 102         /** Returns a new instance of the property editor for the
 103          ** specified class.
 104          ** @param editedClass the class that the property editor
 105          **        will edit.
 106          ** @return a PropertyEditor instance that can edit the
 107          **         specified class.
 108          **/
 109         public static PropertyEditor findEditor(Class editedClass) {
 110                 try {
 111
 112                 Class found = (Class)editors.get(editedClass);
 113                 if(found != null) {
 114                         return (PropertyEditor)found.newInstance();
 115                 }
 116
 117                 try {
 118                         found = Class.forName(editedClass.getName()+"Editor");
 119                         registerEditor(editedClass,found);
 120                         return (PropertyEditor)found.newInstance();
 121                 } catch(ClassNotFoundException E) {
 122                 }
 123
 124                 String appendName = "." + ClassHelper.getTruncatedClassName(editedClass) + "Editor";
 125                 synchronized(editorSearchPath) {
 126                         for(int i=0;i<editorSearchPath.length;i++) {
 127                                 try {
 128                                         found = Class.forName(editorSearchPath[i] + appendName);
 129                                         registerEditor(editedClass,found);
 130                                         return (PropertyEditor)found.newInstance();
 131                                 } catch(ClassNotFoundException E) {
 132                                 }
 133                         }
 134                 }
 135
 136                 } catch(InstantiationException E) {
 137                 } catch(IllegalAccessException E) {
 138                 }
 139                 return null;
 140         }
 141
 142         /** Get the editor search path.
 143          ** As a minor departure from the spec, the default value
 144          ** for the editor search path is "gnu.java.beans.editors",
 145          ** "sun.beans.editors".
 146          ** @return the editor search path.
 147          **/
 148         public static String[] getEditorSearchPath() {
 149                 return editorSearchPath;
 150         }
 151
 152         /** Set the editor search path.
 153          ** @param editorSearchPath the new value for the editor
 154          **        search path.
 155          **/
 156         public static void setEditorSearchPath(String[] editorSearchPath) {
 157                 synchronized(editorSearchPath) {
 158                         PropertyEditorManager.editorSearchPath = editorSearchPath;
 159                 }
 160         }
 161 }