libjava/java/beans/PropertyEditorManager.java

/* java.beans.PropertyEditorManager
   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;

import gnu.java.lang.ClassHelper;

/**
 ** PropertyEditorManager is used to find property editors
 ** for various types (not necessarily Beans).<P>
 **
 ** It first checks to see if the property editor is
 ** already registered; if it is, that property editor is
 ** used.  Next it takes the type's classname and appends
 ** "Editor" to it, and searches first in the class's
 ** package and then in the property editor search path.<P>
 **
 ** Default property editors are provided for:<P>
 ** <OL>
 ** <LI>boolean, byte, short, int, long, float, and double</LI>
 ** <LI>java.lang.String</LI>
 ** <LI>java.awt.Color</LI>
 ** <LI>java.awt.Font</LI>
 ** <OL>
 **
 ** <STRONG>Spec Suggestion:</STRONG> Perhaps an editor for
 ** Filename or something like it should be provided.  As well
 ** as char.
 **
 ** @author John Keiser
 ** @since JDK1.1
 ** @version 1.1.0, 29 Jul 1998
 **/

public class PropertyEditorManager {
	static java.util.Hashtable editors = new java.util.Hashtable();
	static String[] editorSearchPath = {"gnu.java.beans.editors","sun.beans.editors"};

	static {
		registerEditor(java.lang.Boolean.TYPE, gnu.java.beans.editors.NativeBooleanEditor.class);
		registerEditor(java.lang.Byte.TYPE,    gnu.java.beans.editors.NativeByteEditor.class);
		registerEditor(java.lang.Short.TYPE,   gnu.java.beans.editors.NativeShortEditor.class);
		registerEditor(java.lang.Integer.TYPE, gnu.java.beans.editors.NativeIntEditor.class);
		registerEditor(java.lang.Long.TYPE,    gnu.java.beans.editors.NativeLongEditor.class);
		registerEditor(java.lang.Float.TYPE,   gnu.java.beans.editors.NativeFloatEditor.class);
		registerEditor(java.lang.Double.TYPE,  gnu.java.beans.editors.NativeDoubleEditor.class);
		registerEditor(java.lang.String.class, gnu.java.beans.editors.StringEditor.class);
		registerEditor(java.awt.Color.class,   gnu.java.beans.editors.ColorEditor.class);
		registerEditor(java.awt.Font.class,    gnu.java.beans.editors.FontEditor.class);
	}

	/** Beats me why this class can be instantiated, but there
	 ** you have it.
	 **/
	public PropertyEditorManager() { }

	/** Register an editor for a class.  Replaces old editor
	 ** if there was one registered before.
	 ** @param editedClass the class that the property editor
	 **        will edit.
	 ** @param editorClass the PropertyEditor class.
	 **/
	public static void registerEditor(Class editedClass, Class editorClass) {
		editors.put(editedClass, editorClass);
	}

	/** Returns a new instance of the property editor for the
	 ** specified class.
	 ** @param editedClass the class that the property editor
	 **        will edit.
	 ** @return a PropertyEditor instance that can edit the
	 **         specified class.
	 **/
	public static PropertyEditor findEditor(Class editedClass) {
		try {

		Class found = (Class)editors.get(editedClass);
		if(found != null) {
			return (PropertyEditor)found.newInstance();
		}

		try {
			found = Class.forName(editedClass.getName()+"Editor");
			registerEditor(editedClass,found);
			return (PropertyEditor)found.newInstance();
		} catch(ClassNotFoundException E) {
		}

		String appendName = "." + ClassHelper.getTruncatedClassName(editedClass) + "Editor";
		synchronized(editorSearchPath) {
			for(int i=0;i<editorSearchPath.length;i++) {
				try {
					found = Class.forName(editorSearchPath[i] + appendName);
					registerEditor(editedClass,found);
					return (PropertyEditor)found.newInstance();
				} catch(ClassNotFoundException E) {
				}
			}
		}

		} catch(InstantiationException E) {
		} catch(IllegalAccessException E) {
		}
		return null;
	}

	/** Get the editor search path.
	 ** As a minor departure from the spec, the default value
	 ** for the editor search path is "gnu.java.beans.editors",
	 ** "sun.beans.editors".
	 ** @return the editor search path.
	 **/
	public static String[] getEditorSearchPath() {
		return editorSearchPath;
	}

	/** Set the editor search path.
	 ** @param editorSearchPath the new value for the editor
	 **        search path.
	 **/
	public static void setEditorSearchPath(String[] editorSearchPath) {
		synchronized(editorSearchPath) {
			PropertyEditorManager.editorSearchPath = editorSearchPath;
		}
	}
}