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 import gnu.java.beans.editors.ColorEditor;
43 import gnu.java.beans.editors.FontEditor;
44 import gnu.java.beans.editors.NativeBooleanEditor;
45 import gnu.java.beans.editors.NativeByteEditor;
46 import gnu.java.beans.editors.NativeDoubleEditor;
47 import gnu.java.beans.editors.NativeFloatEditor;
48 import gnu.java.beans.editors.NativeIntEditor;
49 import gnu.java.beans.editors.NativeLongEditor;
50 import gnu.java.beans.editors.NativeShortEditor;
51 import gnu.java.beans.editors.StringEditor;
52 import java.awt.Color;
53 import java.awt.Font;
54 
55 /**
56  * PropertyEditorManager is used to find property editors
57  * for various types (not necessarily Beans).<P>
58  *
59  * It first checks to see if the property editor is
60  * already registered; if it is, that property editor is
61  * used.  Next it takes the type's classname and appends
62  * "Editor" to it, and searches first in the class's
63  * package and then in the property editor search path.<P>
64  *
65  * Default property editors are provided for:<P>
66  * <OL>
67  * <LI>boolean, byte, short, int, long, float, and double</LI>
68  * <LI>java.lang.String</LI>
69  * <LI>java.awt.Color</LI>
70  * <LI>java.awt.Font</LI>
71  * <OL>
72  *
73  * <STRONG>Spec Suggestion:</STRONG> Perhaps an editor for
74  * Filename or something like it should be provided.  As well
75  * as char.
76  *
77  * @author John Keiser
78  * @since 1.1
79  * @version 1.1.0, 29 Jul 1998
80  */
81 
82 public class PropertyEditorManager
83 {
84   static java.util.Hashtable editors = new java.util.Hashtable();
85   static String[] editorSearchPath = { "gnu.java.beans.editors",
86                                        "sun.beans.editors" };
87 
88   static
89     {
registerEditor(Boolean.TYPE, NativeBooleanEditor.class)90       registerEditor(Boolean.TYPE, NativeBooleanEditor.class);
registerEditor(Byte.TYPE, NativeByteEditor.class)91       registerEditor(Byte.TYPE,    NativeByteEditor.class);
registerEditor(Short.TYPE, NativeShortEditor.class)92       registerEditor(Short.TYPE,   NativeShortEditor.class);
registerEditor(Integer.TYPE, NativeIntEditor.class)93       registerEditor(Integer.TYPE, NativeIntEditor.class);
registerEditor(Long.TYPE, NativeLongEditor.class)94       registerEditor(Long.TYPE,    NativeLongEditor.class);
registerEditor(Float.TYPE, NativeFloatEditor.class)95       registerEditor(Float.TYPE,   NativeFloatEditor.class);
registerEditor(Double.TYPE, NativeDoubleEditor.class)96       registerEditor(Double.TYPE,  NativeDoubleEditor.class);
registerEditor(String.class, StringEditor.class)97       registerEditor(String.class, StringEditor.class);
registerEditor(Color.class, ColorEditor.class)98       registerEditor(Color.class,  ColorEditor.class);
registerEditor(Font.class, FontEditor.class)99       registerEditor(Font.class,   FontEditor.class);
100     }
101 
102   /**
103    * Beats me why this class can be instantiated, but there
104    * you have it.
105    */
PropertyEditorManager()106   public PropertyEditorManager()
107   {
108     // Do nothing here
109   }
110 
111   /**
112    * Register an editor for a class.  Replaces old editor
113    * if there was one registered before.
114    *
115    * @param editedClass the class that the property editor
116    *        will edit.
117    * @param editorClass the PropertyEditor class.
118    */
registerEditor(Class editedClass, Class editorClass)119   public static void registerEditor(Class editedClass, Class editorClass)
120   {
121     editors.put(editedClass, editorClass);
122   }
123 
124   /**
125    * Returns a new instance of the property editor for the
126    * specified class.
127    *
128    * @param editedClass the class that the property editor
129    *        will edit.
130    * @return a PropertyEditor instance that can edit the
131    *         specified class.
132    */
findEditor(Class editedClass)133   public static PropertyEditor findEditor(Class editedClass)
134   {
135     try
136       {
137         Class found = (Class)editors.get(editedClass);
138         if(found != null)
139           {
140             return (PropertyEditor)found.newInstance();
141           }
142 
143 	ClassLoader contextClassLoader
144 		= Thread.currentThread().getContextClassLoader();
145 
146         try
147           {
148             found = Class.forName(editedClass.getName()+"Editor", true,
149 				  contextClassLoader);
150             registerEditor(editedClass,found);
151             return (PropertyEditor)found.newInstance();
152           }
153         catch(ClassNotFoundException E)
154           {
155           }
156 
157         String appendName
158 		= "."
159 		+ ClassHelper.getTruncatedClassName(editedClass)
160 		+ "Editor";
161         synchronized(editorSearchPath)
162           {
163             for(int i=0;i<editorSearchPath.length;i++)
164               {
165                 try
166                   {
167                     found = Class.forName(editorSearchPath[i] + appendName,
168 					  true, contextClassLoader);
169                     registerEditor(editedClass,found);
170                     return (PropertyEditor)found.newInstance();
171                   }
172                 catch(ClassNotFoundException E)
173                   {
174                   }
175               }
176           }
177       }
178     catch(InstantiationException E)
179       {
180       }
181     catch(IllegalAccessException E)
182       {
183       }
184 
185     return null;
186   }
187 
188   /**
189    * Get the editor search path.
190    * As a minor departure from the spec, the default value
191    * for the editor search path is "gnu.java.beans.editors",
192    * "sun.beans.editors".
193    *
194    * @return the editor search path.
195    */
getEditorSearchPath()196   public static String[] getEditorSearchPath()
197   {
198     return editorSearchPath;
199   }
200 
201   /**
202    * Set the editor search path.
203    *
204    * @param editorSearchPath the new value for the editor search path.
205    */
setEditorSearchPath(String[] editorSearchPath)206   public static void setEditorSearchPath(String[] editorSearchPath)
207   {
208     synchronized(editorSearchPath)
209       {
210         PropertyEditorManager.editorSearchPath = editorSearchPath;
211       }
212   }
213 }
214