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	/*
	* Copyright (c) 1996, 2003, 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;

	/**
	* A PropertyEditor class provides support for GUIs that want to
	* allow users to edit a property value of a given type.
	* <p>
	* PropertyEditor supports a variety of different kinds of ways of
	* displaying and updating property values. Most PropertyEditors will
	* only need to support a subset of the different options available in
	* this API.
	* <P>
	* Simple PropertyEditors may only support the getAsText and setAsText
	* methods and need not support (say) paintValue or getCustomEditor. More
	* complex types may be unable to support getAsText and setAsText but will
	* instead support paintValue and getCustomEditor.
	* <p>
	* Every propertyEditor must support one or more of the three simple
	* display styles. Thus it can either (1) support isPaintable or (2)
	* both return a non-null String[] from getTags() and return a non-null
	* value from getAsText or (3) simply return a non-null String from
	* getAsText().
	* <p>
	* Every property editor must support a call on setValue when the argument
	* object is of the type for which this is the corresponding propertyEditor.
	* In addition, each property editor must either support a custom editor,
	* or support setAsText.
	* <p>
	* Each PropertyEditor should have a null constructor.
	*/

	public interface PropertyEditor {

	/**
	* Set (or change) the object that is to be edited. Primitive types such
	* as "int" must be wrapped as the corresponding object type such as
	* "java.lang.Integer".
	*
	* @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.
	*/
	void setValue(Object value);

	/**
	* Gets the property value.
	*
	* @return The value of the property. Primitive types such as "int" will
	* be wrapped as the corresponding object type such as "java.lang.Integer".
	*/

	Object getValue();

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

	/**
	* Determines whether this property editor is paintable.
	*
	* @return True if the class will honor the paintValue method.
	*/

	boolean isPaintable();

	/**
	* 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.
	* <p>
	* The given Graphics object will have the default font, color, etc of
	* the parent container. The PropertyEditor may change graphics attributes
	* such as font and color and doesn't need to restore the old values.
	*
	* @param gfx Graphics object to paint into.
	* @param box Rectangle within graphics object into which we should paint.
	*/
	void paintValue(java.awt.Graphics gfx, java.awt.Rectangle box);

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

	/**
	* Returns a fragment of Java code that can be used to set a property
	* to match the editors current state. This method is intended
	* for use when generating Java code to reflect changes made through the
	* property editor.
	* <p>
	* The code fragment should be context free and must be a legal Java
	* expression as specified by the JLS.
	* <p>
	* Specifically, if the expression represents a computation then all
	* classes and static members should be fully qualified. This rule
	* applies to constructors, static methods and non primitive arguments.
	* <p>
	* Caution should be used when evaluating the expression as it may throw
	* exceptions. In particular, code generators must ensure that generated
	* code will compile in the presence of an expression that can throw
	* checked exceptions.
	* <p>
	* Example results are:
	* <ul>
	* <li>Primitive expresssion: <code>2</code>
	* <li>Class constructor: <code>new java.awt.Color(127,127,34)</code>
	* <li>Static field: <code>java.awt.Color.orange</code>
	* <li>Static method: <code>javax.swing.Box.createRigidArea(new
	* java.awt.Dimension(0, 5))</code>
	* </ul>
	*
	* @return a fragment of Java code representing an initializer for the
	* current value. It should not contain a semi-colon
	* ('<code>;</code>') to end the expression.
	*/
	String getJavaInitializationString();

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

	/**
	* Gets the property value as text.
	*
	* @return The property value as a human editable string.
	* <p> Returns null if the value can't be expressed as an editable string.
	* <p> If a non-null value is returned, then the PropertyEditor should
	* be prepared to parse that string back in setAsText().
	*/
	String getAsText();

	/**
	* Set 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.
	*/
	void setAsText(String text) throws java.lang.IllegalArgumentException;

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

	/**
	* If the property value must be one of a set of known tagged values,
	* then this method should return an array of the tags. 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 and the use of getAsText
	* to identify the current value.
	*
	* @return The tag values for this property. May be null if this
	* property cannot be represented as a tagged value.
	*
	*/
	String[] getTags();

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

	/**
	* A PropertyEditor may choose 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.
	*/

	java.awt.Component getCustomEditor();

	/**
	* Determines whether this property editor supports a custom editor.
	*
	* @return True if the propertyEditor can provide a custom editor.
	*/
	boolean supportsCustomEditor();

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

	/**
	* 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
	* and itself as the source.
	*
	* @param listener the {@link PropertyChangeListener} to add
	*/
	void addPropertyChangeListener(PropertyChangeListener listener);

	/**
	* Removes a listener for the value change.
	*
	* @param listener the {@link PropertyChangeListener} to remove
	*/
	void removePropertyChangeListener(PropertyChangeListener listener);

	}

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