/* * 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); }