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1   /*
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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
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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
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19   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20   *
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24   */
25  package java.awt;
26  
27  import java.awt.event.KeyEvent;
28  
29  /**
30   * The <code>MenuShortcut</code>class represents a keyboard accelerator
31   * for a MenuItem.
32   * <p>
33   * Menu shortcuts are created using virtual keycodes, not characters.
34   * For example, a menu shortcut for Ctrl-a (assuming that Control is
35   * the accelerator key) would be created with code like the following:
36   * <p>
37   * <code>MenuShortcut ms = new MenuShortcut(KeyEvent.VK_A, false);</code>
38   * <p> or alternatively
39   * <p>
40   * <code>MenuShortcut ms = new MenuShortcut(KeyEvent.getExtendedKeyCodeForChar('A'), false);</code>
41   * <p>
42   * Menu shortcuts may also be constructed for a wider set of keycodes
43   * using the <code>java.awt.event.KeyEvent.getExtendedKeyCodeForChar</code> call.
44   * For example, a menu shortcut for "Ctrl+cyrillic ef" is created by
45   * <p>
46   * <code>MenuShortcut ms = new MenuShortcut(KeyEvent.getExtendedKeyCodeForChar('\u0444'), false);</code>
47   * <p>
48   * Note that shortcuts created with a keycode or an extended keycode defined as a constant in <code>KeyEvent</code>
49   * work regardless of the current keyboard layout. However, a shortcut made of
50   * an extended keycode not listed in <code>KeyEvent</code>
51   * only work if the current keyboard layout produces a corresponding letter.
52   * <p>
53   * The accelerator key is platform-dependent and may be obtained
54   * via {@link Toolkit#getMenuShortcutKeyMask}.
55   *
56   * @author Thomas Ball
57   * @since JDK1.1
58   */
59  public class MenuShortcut implements java.io.Serializable
60  {
61      /**
62       * The virtual keycode for the menu shortcut.
63       * This is the keycode with which the menu shortcut will be created.
64       * Note that it is a virtual keycode, not a character,
65       * e.g. KeyEvent.VK_A, not 'a'.
66       * Note: in 1.1.x you must use setActionCommand() on a menu item
67       * in order for its shortcut to work, otherwise it will fire a null
68       * action command.
69       *
70       * @serial
71       * @see #getKey()
72       * @see #usesShiftModifier()
73       * @see java.awt.event.KeyEvent
74       * @since JDK1.1
75       */
76      int key;
77  
78      /**
79       * Indicates whether the shft key was pressed.
80       * If true, the shift key was pressed.
81       * If false, the shift key was not pressed
82       *
83       * @serial
84       * @see #usesShiftModifier()
85       * @since JDK1.1
86       */
87      boolean usesShift;
88  
89      /*
90       * JDK 1.1 serialVersionUID
91       */
92       private static final long serialVersionUID = 143448358473180225L;
93  
94      /**
95       * Constructs a new MenuShortcut for the specified virtual keycode.
96       * @param key the raw keycode for this MenuShortcut, as would be returned
97       * in the keyCode field of a {@link java.awt.event.KeyEvent KeyEvent} if
98       * this key were pressed.
99       * @see java.awt.event.KeyEvent
100      **/
101     public MenuShortcut(int key) {
102         this(key, false);
103     }
104 
105     /**
106      * Constructs a new MenuShortcut for the specified virtual keycode.
107      * @param key the raw keycode for this MenuShortcut, as would be returned
108      * in the keyCode field of a {@link java.awt.event.KeyEvent KeyEvent} if
109      * this key were pressed.
110      * @param useShiftModifier indicates whether this MenuShortcut is invoked
111      * with the SHIFT key down.
112      * @see java.awt.event.KeyEvent
113      **/
114     public MenuShortcut(int key, boolean useShiftModifier) {
115         this.key = key;
116         this.usesShift = useShiftModifier;
117     }
118 
119     /**
120      * Returns the raw keycode of this MenuShortcut.
121      * @return the raw keycode of this MenuShortcut.
122      * @see java.awt.event.KeyEvent
123      * @since JDK1.1
124      */
125     public int getKey() {
126         return key;
127     }
128 
129     /**
130      * Returns whether this MenuShortcut must be invoked using the SHIFT key.
131      * @return <code>true</code> if this MenuShortcut must be invoked using the
132      * SHIFT key, <code>false</code> otherwise.
133      * @since JDK1.1
134      */
135     public boolean usesShiftModifier() {
136         return usesShift;
137     }
138 
139     /**
140      * Returns whether this MenuShortcut is the same as another:
141      * equality is defined to mean that both MenuShortcuts use the same key
142      * and both either use or don't use the SHIFT key.
143      * @param s the MenuShortcut to compare with this.
144      * @return <code>true</code> if this MenuShortcut is the same as another,
145      * <code>false</code> otherwise.
146      * @since JDK1.1
147      */
148     public boolean equals(MenuShortcut s) {
149         return (s != null && (s.getKey() == key) &&
150                 (s.usesShiftModifier() == usesShift));
151     }
152 
153     /**
154      * Returns whether this MenuShortcut is the same as another:
155      * equality is defined to mean that both MenuShortcuts use the same key
156      * and both either use or don't use the SHIFT key.
157      * @param obj the Object to compare with this.
158      * @return <code>true</code> if this MenuShortcut is the same as another,
159      * <code>false</code> otherwise.
160      * @since 1.2
161      */
162     public boolean equals(Object obj) {
163         if (obj instanceof MenuShortcut) {
164             return equals( (MenuShortcut) obj );
165         }
166         return false;
167     }
168 
169     /**
170      * Returns the hashcode for this MenuShortcut.
171      * @return the hashcode for this MenuShortcut.
172      * @since 1.2
173      */
174     public int hashCode() {
175         return (usesShift) ? (~key) : key;
176     }
177 
178     /**
179      * Returns an internationalized description of the MenuShortcut.
180      * @return a string representation of this MenuShortcut.
181      * @since JDK1.1
182      */
183     public String toString() {
184         int modifiers = 0;
185         if (!GraphicsEnvironment.isHeadless()) {
186             modifiers = Toolkit.getDefaultToolkit().getMenuShortcutKeyMask();
187         }
188         if (usesShiftModifier()) {
189             modifiers |= Event.SHIFT_MASK;
190         }
191         return KeyEvent.getKeyModifiersText(modifiers) + "+" +
192                KeyEvent.getKeyText(key);
193     }
194 
195     /**
196      * Returns the parameter string representing the state of this
197      * MenuShortcut. This string is useful for debugging.
198      * @return    the parameter string of this MenuShortcut.
199      * @since JDK1.1
200      */
201     protected String paramString() {
202         String str = "key=" + key;
203         if (usesShiftModifier()) {
204             str += ",usesShiftModifier";
205         }
206         return str;
207     }
208 }