1 /*
2 * Copyright (c) 1997, 2008, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25 package javax.swing.text;
26
27 import java.awt.event.ActionEvent;
28 import java.awt.KeyboardFocusManager;
29 import java.awt.Component;
30 import java.util.Hashtable;
31 import java.util.Enumeration;
32 import javax.swing.Action;
33 import javax.swing.AbstractAction;
34 import javax.swing.KeyStroke;
35
36 /**
37 * An Action implementation useful for key bindings that are
38 * shared across a number of different text components. Because
39 * the action is shared, it must have a way of getting it's
40 * target to act upon. This class provides support to try and
41 * find a text component to operate on. The preferred way of
42 * getting the component to act upon is through the ActionEvent
43 * that is received. If the Object returned by getSource can
44 * be narrowed to a text component, it will be used. If the
45 * action event is null or can't be narrowed, the last focused
46 * text component is tried. This is determined by being
47 * used in conjunction with a JTextController which
48 * arranges to share that information with a TextAction.
49 * <p>
50 * <strong>Warning:</strong>
51 * Serialized objects of this class will not be compatible with
52 * future Swing releases. The current serialization support is
53 * appropriate for short term storage or RMI between applications running
54 * the same version of Swing. As of 1.4, support for long term storage
55 * of all JavaBeans™
56 * has been added to the <code>java.beans</code> package.
57 * Please see {@link java.beans.XMLEncoder}.
58 *
59 * @author Timothy Prinzing
60 */
61 public abstract class TextAction extends AbstractAction {
62
63 /**
64 * Creates a new JTextAction object.
65 *
66 * @param name the name of the action
67 */
68 public TextAction(String name) {
69 super(name);
70 }
71
72 /**
73 * Determines the component to use for the action.
74 * This if fetched from the source of the ActionEvent
75 * if it's not null and can be narrowed. Otherwise,
76 * the last focused component is used.
77 *
78 * @param e the ActionEvent
79 * @return the component
80 */
81 protected final JTextComponent getTextComponent(ActionEvent e) {
82 if (e != null) {
83 Object o = e.getSource();
84 if (o instanceof JTextComponent) {
85 return (JTextComponent) o;
86 }
87 }
88 return getFocusedComponent();
89 }
90
91 /**
92 * Takes one list of
93 * commands and augments it with another list
94 * of commands. The second list takes precedence
95 * over the first list; that is, when both lists
96 * contain a command with the same name, the command
97 * from the second list is used.
98 *
99 * @param list1 the first list, may be empty but not
100 * <code>null</code>
101 * @param list2 the second list, may be empty but not
102 * <code>null</code>
103 * @return the augmented list
104 */
105 public static final Action[] augmentList(Action[] list1, Action[] list2) {
106 Hashtable<String, Action> h = new Hashtable<String, Action>();
107 for (Action a : list1) {
108 String value = (String)a.getValue(Action.NAME);
109 h.put((value!=null ? value:""), a);
110 }
111 for (Action a : list2) {
112 String value = (String)a.getValue(Action.NAME);
113 h.put((value!=null ? value:""), a);
114 }
115 Action[] actions = new Action[h.size()];
116 int index = 0;
117 for (Enumeration e = h.elements() ; e.hasMoreElements() ;) {
118 actions[index++] = (Action) e.nextElement();
119 }
120 return actions;
121 }
122
123 /**
124 * Fetches the text component that currently has focus.
125 * This allows actions to be shared across text components
126 * which is useful for key-bindings where a large set of
127 * actions are defined, but generally used the same way
128 * across many different components.
129 *
130 * @return the component
131 */
132 protected final JTextComponent getFocusedComponent() {
133 return JTextComponent.getFocusedComponent();
134 }
135 }