/* * @(#)TextAction.java 1.29 03/12/19 * * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. */ package javax.swing.text; import java.awt.event.ActionEvent; import java.awt.KeyboardFocusManager; import java.awt.Component; import java.util.Hashtable; import java.util.Enumeration; import javax.swing.Action; import javax.swing.AbstractAction; import javax.swing.KeyStroke; /** * An Action implementation useful for key bindings that are * shared across a number of different text components. Because * the action is shared, it must have a way of getting it's * target to act upon. This class provides support to try and * find a text component to operate on. The preferred way of * getting the component to act upon is through the ActionEvent * that is received. If the Object returned by getSource can * be narrowed to a text component, it will be used. If the * action event is null or can't be narrowed, the last focused * text component is tried. This is determined by being * used in conjunction with a JTextController which * arranges to share that information with a TextAction. *
* Warning:
* Serialized objects of this class will not be compatible with
* future Swing releases. The current serialization support is
* appropriate for short term storage or RMI between applications running
* the same version of Swing. As of 1.4, support for long term storage
* of all JavaBeansTM
* has been added to the java.beans
package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Timothy Prinzing
* @version 1.29 12/19/03
*/
public abstract class TextAction extends AbstractAction {
/**
* Creates a new JTextAction object.
*
* @param name the name of the action
*/
public TextAction(String name) {
super(name);
}
/**
* Determines the component to use for the action.
* This if fetched from the source of the ActionEvent
* if it's not null and can be narrowed. Otherwise,
* the last focused component is used.
*
* @param e the ActionEvent
* @return the component
*/
protected final JTextComponent getTextComponent(ActionEvent e) {
if (e != null) {
Object o = e.getSource();
if (o instanceof JTextComponent) {
return (JTextComponent) o;
}
}
return getFocusedComponent();
}
/**
* Takes one list of
* commands and augments it with another list
* of commands. The second list takes precedence
* over the first list; that is, when both lists
* contain a command with the same name, the command
* from the second list is used.
*
* @param list1 the first list, may be empty but not
* null
* @param list2 the second list, may be empty but not
* null
* @return the augmented list
*/
public static final Action[] augmentList(Action[] list1, Action[] list2) {
Hashtable h = new Hashtable();
for (int i = 0; i < list1.length; i++) {
Action a = list1[i];
String value = (String)a.getValue(Action.NAME);
h.put((value!=null ? value:""), a);
}
for (int i = 0; i < list2.length; i++) {
Action a = list2[i];
String value = (String)a.getValue(Action.NAME);
h.put((value!=null ? value:""), a);
}
Action[] actions = new Action[h.size()];
int index = 0;
for (Enumeration e = h.elements() ; e.hasMoreElements() ;) {
actions[index++] = (Action) e.nextElement();
}
return actions;
}
/**
* Fetches the text component that currently has focus.
* This allows actions to be shared across text components
* which is useful for key-bindings where a large set of
* actions are defined, but generally used the same way
* across many different components.
*
* @return the component
*/
protected final JTextComponent getFocusedComponent() {
return JTextComponent.getFocusedComponent();
}
}