Java tutorial
/* * Copyright (c) 1997, 2014, 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 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>DefaultCellEditor</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 * @since 1.2 */ 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); }