| /* java.beans.PropertyEditorSupport |
| Copyright (C) 1998 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| As a special exception, if you link this library with other files to |
| produce an executable, this library does not by itself cause the |
| resulting executable to be covered by the GNU General Public License. |
| This exception does not however invalidate any other reasons why the |
| executable file might be covered by the GNU General Public License. */ |
| |
| |
| package java.beans; |
| |
| /** |
| ** PropertyEditorSupport helps with PropertyEditors, |
| ** implementing base functionality that they usually must |
| ** have but which is a pain to implement. You may extend |
| ** from this class or use it as a standalone.<P> |
| ** |
| ** This class does not do any painting or actual editing. |
| ** For that, you must use or extend it. See the |
| ** PropertyEditor class for better descriptions of what |
| ** the various methods do. |
| ** |
| ** @author John Keiser |
| ** @since JDK1.1 |
| ** @version 1.1.0, 29 Jul 1998 |
| **/ |
| |
| public class PropertyEditorSupport implements PropertyEditor { |
| Object eventSource; |
| Object val; |
| PropertyChangeSupport pSupport; |
| |
| /** Call this constructor when you are deriving from |
| ** PropertyEditorSupport. |
| **/ |
| protected PropertyEditorSupport() { |
| this.eventSource = this; |
| this.pSupport = new PropertyChangeSupport(this); |
| } |
| |
| /** Call this constructor when you are using |
| ** PropertyEditorSupport as a helper object. |
| ** @param eventSource the source to use when firing |
| ** property change events. |
| **/ |
| protected PropertyEditorSupport(Object eventSource) { |
| this.eventSource = eventSource; |
| this.pSupport = new PropertyChangeSupport(this); |
| } |
| |
| /** Set the current value of the property. |
| ** <STRONG>Implementation Note</STRONG> Sun does not |
| ** state what exactly this version of the method does. |
| ** Thus, in this implementation, it sets the value, and |
| ** then if the old and new values are different, it |
| ** fires a property change event with no property name |
| ** and the old and new values. |
| ** @param val the new value for the property. |
| **/ |
| public void setValue(Object val) { |
| Object oldVal = val; |
| this.val = val; |
| if(!oldVal.equals(val)) { |
| pSupport.firePropertyChange(null,oldVal,val); |
| } |
| } |
| |
| /** Get the current value of the property. |
| ** @return the current value of the property. |
| **/ |
| public Object getValue() { |
| return val; |
| } |
| |
| /** Get whether this object is paintable or not. |
| ** @return <CODE>false</CODE> |
| **/ |
| public boolean isPaintable() { |
| return false; |
| } |
| |
| /** Paint this object. This class does nothing in |
| ** this method. |
| **/ |
| public void paintValue(java.awt.Graphics g, java.awt.Rectangle r) { |
| } |
| |
| /** Get the Java initialization String for the current |
| ** value of the Object. This class returns gibberish or |
| ** null (though the spec does not say which).<P> |
| ** <STRONG>Implementation Note:</STRONG> This class |
| ** returns the string "@$#^" to make sure the code will |
| ** be broken, so that you will know to override it when |
| ** you create your own property editor. |
| ** @return the Java initialization string. |
| **/ |
| public String getJavaInitializationString() { |
| return "@$#^"; |
| } |
| |
| /** Get the value as text. |
| ** In this class, you cannot count on getAsText() doing |
| ** anything useful, although in this implementation I |
| ** do toString(). |
| ** @return the value as text. |
| **/ |
| public String getAsText() { |
| return val != null ? val.toString() : "null"; |
| } |
| |
| /** Set the value as text. |
| ** In this class, you cannot count on setAsText() doing |
| ** anything useful across implementations. |
| ** <STRONG>Implementation Note:</STRONG> In this |
| ** implementation it checks if the String is "null", and |
| ** if it is, sets the value to null, otherwise it throws |
| ** an IllegalArgumentException. |
| ** @param s the text to convert to a new value. |
| ** @exception IllegalArgumentException if the text is |
| ** malformed. |
| **/ |
| public void setAsText(String s) throws IllegalArgumentException { |
| if(s.equals("null")) { |
| setValue(null); |
| } else { |
| throw new IllegalArgumentException(); |
| } |
| } |
| |
| /** Returns a list of possible choices for the value. |
| ** @return <CODE>null</CODE> |
| **/ |
| public String[] getTags() { |
| return null; |
| } |
| |
| /** Return a custom component to edit the value. |
| ** @return <CODE>null</CODE> in this class. |
| **/ |
| public java.awt.Component getCustomEditor() { |
| return null; |
| } |
| |
| /** Find out whether this property editor supports a |
| ** custom component to edit its value. |
| ** @return <CODE>false</CODE> in this class. |
| **/ |
| public boolean supportsCustomEditor() { |
| return false; |
| } |
| |
| /** Add a property change listener to this property editor. |
| ** @param l the listener to add. |
| **/ |
| public void addPropertyChangeListener(PropertyChangeListener l) { |
| pSupport.addPropertyChangeListener(l); |
| } |
| |
| /** Remove a property change listener from this property editor. |
| ** @param l the listener to remove. |
| **/ |
| public void removePropertyChangeListener(PropertyChangeListener l) { |
| pSupport.removePropertyChangeListener(l); |
| } |
| |
| |
| /** Notify people that we've changed, although we don't |
| ** tell them just how. The only thing I can think of to |
| ** send in the event is the new value (since the old value |
| ** is unavailable and there is no property name). |
| ** I confess I do not understand the point of this method. |
| **/ |
| public void firePropertyChange() { |
| pSupport.firePropertyChange(null,null,val); |
| } |
| } |
| |