/*

 * Copyright 1997-2005 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 javax.swing;

import java.util.EventObject;

import javax.swing.event.*;

/**

 * This interface defines the methods any general editor should be able

 * to implement. <p>

 *

 * Having this interface enables complex components (the client of the

 * editor) such as <code>JTree</code> and

 * <code>JTable</code> to allow any generic editor to

 * edit values in a table cell, or tree cell, etc.  Without this generic

 * editor interface, <code>JTable</code> would have to know about specific editors,

 * such as <code>JTextField</code>, <code>JCheckBox</code>, <code>JComboBox</code>,

 * etc.  In addition, without this interface, clients of editors such as

 * <code>JTable</code> would not be able

 * to work with any editors developed in the future by the user

 * or a 3rd party ISV. <p>

 *

 * To use this interface, a developer creating a new editor can have the

 * new component implement the interface.  Or the developer can

 * choose a wrapper based approach and provide a companion object which

 * implements the <code>CellEditor</code> interface (See

 * <code>JCellEditor</code> for example).  The wrapper approach

 * is particularly useful if the user want to use a 3rd party ISV

 * editor with <code>JTable</code>, but the ISV didn't implement the

 * <code>CellEditor</code> interface.  The user can simply create an object

 * that contains an instance of the 3rd party editor object and "translate"

 * the <code>CellEditor</code> API into the 3rd party editor's API.

 *

 * @see javax.swing.event.CellEditorListener

 *

 * @author Alan Chung

 */

public interface CellEditor {

    /**

     * Returns the value contained in the editor.

     * @return the value contained in the editor

     */

    public Object getCellEditorValue();

    /**

     * Asks the editor if it can start editing using <code>anEvent</code>.

     * <code>anEvent</code> is in the invoking component coordinate system.

     * The editor can not assume the Component returned by

     * <code>getCellEditorComponent</code> is installed.  This method

     * is intended for the use of client to avoid the cost of setting up

     * and installing the editor component if editing is not possible.

     * If editing can be started this method returns true.

     *

     * @param   anEvent         the event the editor should use to consider

     *                          whether to begin editing or not

     * @return  true if editing can be started

     * @see #shouldSelectCell

     */

    public boolean isCellEditable(EventObject anEvent);

    /**

     * Returns true if the editing cell should be selected, false otherwise.

     * Typically, the return value is true, because is most cases the editing

     * cell should be selected.  However, it is useful to return false to

     * keep the selection from changing for some types of edits.

     * eg. A table that contains a column of check boxes, the user might

     * want to be able to change those checkboxes without altering the

     * selection.  (See Netscape Communicator for just such an example)

     * Of course, it is up to the client of the editor to use the return

     * value, but it doesn't need to if it doesn't want to.

     *

     * @param   anEvent         the event the editor should use to start

     *                          editing

     * @return  true if the editor would like the editing cell to be selected;

     *    otherwise returns false

     * @see #isCellEditable

     */

    public boolean shouldSelectCell(EventObject anEvent);

    /**

     * Tells the editor to stop editing and accept any partially edited

     * value as the value of the editor.  The editor returns false if

     * editing was not stopped; this is useful for editors that validate

     * and can not accept invalid entries.

     *

     * @return  true if editing was stopped; false otherwise

     */

    public boolean stopCellEditing();

    /**

     * Tells the editor to cancel editing and not accept any partially

     * edited value.

     */

    public void cancelCellEditing();

    /**

     * Adds a listener to the list that's notified when the editor

     * stops, or cancels editing.

     *

     * @param   l               the CellEditorListener

     */

    public void addCellEditorListener(CellEditorListener l);

    /**

     * Removes a listener from the list that's notified

     *

     * @param   l               the CellEditorListener

     */

    public void removeCellEditorListener(CellEditorListener l);

}