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	/*
	* Copyright (c) 1996, 2013, Oracle and/or its affiliates. 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. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.beans;

	import java.beans.*;

	/**
	* This is a support class to help build property editors.
	* <p>
	* It can be used either as a base class or as a delegate.
	*/

	public class PropertyEditorSupport implements PropertyEditor {

	/**
	* Constructs a <code>PropertyEditorSupport</code> object.
	*
	* @since 1.5
	*/
	public PropertyEditorSupport() {
	setSource(this);
	}

	/**
	* Constructs a <code>PropertyEditorSupport</code> object.
	*
	* @param source the source used for event firing
	* @since 1.5
	*/
	public PropertyEditorSupport(Object source) {
	if (source == null) {
	throw new NullPointerException();
	}
	setSource(source);
	}

	/**
	* Returns the bean that is used as the
	* source of events. If the source has not
	* been explicitly set then this instance of
	* <code>PropertyEditorSupport</code> is returned.
	*
	* @return the source object or this instance
	* @since 1.5
	*/
	public Object getSource() {
	return source;
	}

	/**
	* Sets the source bean.
	* <p>
	* The source bean is used as the source of events
	* for the property changes. This source should be used for information
	* purposes only and should not be modified by the PropertyEditor.
	*
	* @param source source object to be used for events
	* @since 1.5
	*/
	public void setSource(Object source) {
	this.source = source;
	}

	/**
	* Set (or change) the object that is to be edited.
	*
	* @param value The new target object to be edited. Note that this
	* object should not be modified by the PropertyEditor, rather
	* the PropertyEditor should create a new object to hold any
	* modified value.
	*/
	public void setValue(Object value) {
	this.value = value;
	firePropertyChange();
	}

	/**
	* Gets the value of the property.
	*
	* @return The value of the property.
	*/
	public Object getValue() {
	return value;
	}

	//----------------------------------------------------------------------

	/**
	* Determines whether the class will honor the paintValue method.
	*
	* @return True if the class will honor the paintValue method.
	*/

	public boolean isPaintable() {
	return false;
	}

	/**
	* Paint a representation of the value into a given area of screen
	* real estate. Note that the propertyEditor is responsible for doing
	* its own clipping so that it fits into the given rectangle.
	* <p>
	* If the PropertyEditor doesn't honor paint requests (see isPaintable)
	* this method should be a silent noop.
	*
	* @param gfx Graphics object to paint into.
	* @param box Rectangle within graphics object into which we should paint.
	*/
	public void paintValue(java.awt.Graphics gfx, java.awt.Rectangle box) {
	}

	//----------------------------------------------------------------------

	/**
	* This method is intended for use when generating Java code to set
	* the value of the property. It should return a fragment of Java code
	* that can be used to initialize a variable with the current property
	* value.
	* <p>
	* Example results are "2", "new Color(127,127,34)", "Color.orange", etc.
	*
	* @return A fragment of Java code representing an initializer for the
	* current value.
	*/
	public String getJavaInitializationString() {
	return "???";
	}

	//----------------------------------------------------------------------

	/**
	* Gets the property value as a string suitable for presentation
	* to a human to edit.
	*
	* @return The property value as a string suitable for presentation
	* to a human to edit.
	* <p> Returns null if the value can't be expressed as a string.
	* <p> If a non-null value is returned, then the PropertyEditor should
	* be prepared to parse that string back in setAsText().
	*/
	public String getAsText() {
	return (this.value != null)
	? this.value.toString()
	: null;
	}

	/**
	* Sets the property value by parsing a given String. May raise
	* java.lang.IllegalArgumentException if either the String is
	* badly formatted or if this kind of property can't be expressed
	* as text.
	*
	* @param text The string to be parsed.
	*/
	public void setAsText(String text) throws java.lang.IllegalArgumentException {
	if (value instanceof String) {
	setValue(text);
	return;
	}
	throw new java.lang.IllegalArgumentException(text);
	}

	//----------------------------------------------------------------------

	/**
	* If the property value must be one of a set of known tagged values,
	* then this method should return an array of the tag values. This can
	* be used to represent (for example) enum values. If a PropertyEditor
	* supports tags, then it should support the use of setAsText with
	* a tag value as a way of setting the value.
	*
	* @return The tag values for this property. May be null if this
	* property cannot be represented as a tagged value.
	*
	*/
	public String[] getTags() {
	return null;
	}

	//----------------------------------------------------------------------

	/**
	* A PropertyEditor may chose to make available a full custom Component
	* that edits its property value. It is the responsibility of the
	* PropertyEditor to hook itself up to its editor Component itself and
	* to report property value changes by firing a PropertyChange event.
	* <P>
	* The higher-level code that calls getCustomEditor may either embed
	* the Component in some larger property sheet, or it may put it in
	* its own individual dialog, or ...
	*
	* @return A java.awt.Component that will allow a human to directly
	* edit the current property value. May be null if this is
	* not supported.
	*/

	public java.awt.Component getCustomEditor() {
	return null;
	}

	/**
	* Determines whether the propertyEditor can provide a custom editor.
	*
	* @return True if the propertyEditor can provide a custom editor.
	*/
	public boolean supportsCustomEditor() {
	return false;
	}

	//----------------------------------------------------------------------

	/**
	* Adds a listener for the value change.
	* When the property editor changes its value
	* it should fire a {@link PropertyChangeEvent}
	* on all registered {@link PropertyChangeListener}s,
	* specifying the {@code null} value for the property name.
	* If the source property is set,
	* it should be used as the source of the event.
	* <p>
	* The same listener object may be added more than once,
	* and will be called as many times as it is added.
	* If {@code listener} is {@code null},
	* no exception is thrown and no action is taken.
	*
	* @param listener the {@link PropertyChangeListener} to add
	*/
	public synchronized void addPropertyChangeListener(
	PropertyChangeListener listener) {
	if (listeners == null) {
	listeners = new java.util.Vector<>();
	}
	listeners.addElement(listener);
	}

	/**
	* Removes a listener for the value change.
	* <p>
	* If the same listener was added more than once,
	* it will be notified one less time after being removed.
	* If {@code listener} is {@code null}, or was never added,
	* no exception is thrown and no action is taken.
	*
	* @param listener the {@link PropertyChangeListener} to remove
	*/
	public synchronized void removePropertyChangeListener(
	PropertyChangeListener listener) {
	if (listeners == null) {
	return;
	}
	listeners.removeElement(listener);
	}

	/**
	* Report that we have been modified to any interested listeners.
	*/
	public void firePropertyChange() {
	java.util.Vector<PropertyChangeListener> targets;
	synchronized (this) {
	if (listeners == null) {
	return;
	}
	targets = unsafeClone(listeners);
	}
	// Tell our listeners that "everything" has changed.
	PropertyChangeEvent evt = new PropertyChangeEvent(source, null, null, null);

	for (int i = 0; i < targets.size(); i++) {
	PropertyChangeListener target = targets.elementAt(i);
	target.propertyChange(evt);
	}
	}

	@SuppressWarnings("unchecked")
	private <T> java.util.Vector<T> unsafeClone(java.util.Vector<T> v) {
	return (java.util.Vector<T>)v.clone();
	}

	//----------------------------------------------------------------------

	private Object value;
	private Object source;
	private java.util.Vector<PropertyChangeListener> listeners;
	}

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