/*
* Copyright 1996-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
package java.beans;
import sun.beans.editors.*;
/**
* The PropertyEditorManager can be used to locate a property editor for
* any given type name. This property editor must support the
* java.beans.PropertyEditor interface for editing a given object.
* <P>
* The PropertyEditorManager uses three techniques for locating an editor
* for a given type. First, it provides a registerEditor method to allow
* an editor to be specifically registered for a given type. Second it
* tries to locate a suitable class by adding "Editor" to the full
* qualified classname of the given type (e.g. "foo.bah.FozEditor").
* Finally it takes the simple classname (without the package name) adds
* "Editor" to it and looks in a search-path of packages for a matching
* class.
* <P>
* So for an input class foo.bah.Fred, the PropertyEditorManager would
* first look in its tables to see if an editor had been registered for
* foo.bah.Fred and if so use that. Then it will look for a
* foo.bah.FredEditor class. Then it will look for (say)
* standardEditorsPackage.FredEditor class.
* <p>
* Default PropertyEditors will be provided for the Java primitive types
* "boolean", "byte", "short", "int", "long", "float", and "double"; and
* for the classes java.lang.String. java.awt.Color, and java.awt.Font.
*/
public class PropertyEditorManager {
/**
* Register an editor class to be used to edit values of
* a given target class.
*
* <p>First, if there is a security manager, its <code>checkPropertiesAccess</code>
* method is called. This could result in a SecurityException.
*
* @param targetType the Class object of the type to be edited
* @param editorClass the Class object of the editor class. If
* this is null, then any existing definition will be removed.
* @exception SecurityException if a security manager exists and its
* <code>checkPropertiesAccess</code> method doesn't allow setting
* of system properties.
* @see SecurityManager#checkPropertiesAccess
*/
public static void registerEditor(Class<?> targetType, Class<?> editorClass) {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPropertiesAccess();
}
initialize();
if (editorClass == null) {
registry.remove(targetType);
} else {
registry.put(targetType, editorClass);
}
}
/**
* Locate a value editor for a given target type.
*
* @param targetType The Class object for the type to be edited
* @return An editor object for the given target class.
* The result is null if no suitable editor can be found.
*/
public static synchronized PropertyEditor findEditor(Class<?> targetType) {
initialize();
Class editorClass = (Class)registry.get(targetType);
if (editorClass != null) {
try {
Object o = editorClass.newInstance();
return (PropertyEditor)o;
} catch (Exception ex) {
System.err.println("Couldn't instantiate type editor \"" +
editorClass.getName() + "\" : " + ex);
}
}
// Now try adding "Editor" to the class name.
String editorName = targetType.getName() + "Editor";
try {
return (PropertyEditor) Introspector.instantiate(targetType, editorName);
} catch (Exception ex) {
// Silently ignore any errors.
}
// Now try looking for <searchPath>.fooEditor
int index = editorName.lastIndexOf('.') + 1;
if (index > 0) {
editorName = editorName.substring(index);
}
for (String path : searchPath) {
String name = path + '.' + editorName;
try {
return (PropertyEditor) Introspector.instantiate(targetType, name);
} catch (Exception ex) {
// Silently ignore any errors.
}
}
if (null != targetType.getEnumConstants()) {
return new EnumEditor(targetType);
}
// We couldn't find a suitable Editor.
return null;
}
/**
* Gets the package names that will be searched for property editors.
*
* @return The array of package names that will be searched in
* order to find property editors.
* <p> The default value for this array is implementation-dependent,
* e.g. Sun implementation initially sets to {"sun.beans.editors"}.
*/
public static synchronized String[] getEditorSearchPath() {
// Return a copy of the searchPath.
String result[] = new String[searchPath.length];
System.arraycopy(searchPath, 0, result, 0, searchPath.length);
return result;
}
/**
* Change the list of package names that will be used for
* finding property editors.
*
* <p>First, if there is a security manager, its <code>checkPropertiesAccess</code>
* method is called. This could result in a SecurityException.
*
* @param path Array of package names.
* @exception SecurityException if a security manager exists and its
* <code>checkPropertiesAccess</code> method doesn't allow setting
* of system properties.
* @see SecurityManager#checkPropertiesAccess
*/
public static synchronized void setEditorSearchPath(String path[]) {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPropertiesAccess();
}
if (path == null) {
path = new String[0];
}
searchPath = path;
}
private static synchronized void initialize() {
if (registry != null) {
return;
}
registry = new java.util.Hashtable();
registry.put(Byte.TYPE, ByteEditor.class);
registry.put(Short.TYPE, ShortEditor.class);
registry.put(Integer.TYPE, IntegerEditor.class);
registry.put(Long.TYPE, LongEditor.class);
registry.put(Boolean.TYPE, BooleanEditor.class);
registry.put(Float.TYPE, FloatEditor.class);
registry.put(Double.TYPE, DoubleEditor.class);
}
private static String[] searchPath = { "sun.beans.editors" };
private static java.util.Hashtable registry;
}