J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1996-2006 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package java.awt.event; |
| 27 | |
| 28 | import java.awt.AWTEvent; |
| 29 | import java.awt.Event; |
| 30 | |
| 31 | /** |
| 32 | * A semantic event which indicates that a component-defined action occurred. |
| 33 | * This high-level event is generated by a component (such as a |
| 34 | * <code>Button</code>) when |
| 35 | * the component-specific action occurs (such as being pressed). |
| 36 | * The event is passed to every <code>ActionListener</code> object |
| 37 | * that registered to receive such events using the component's |
| 38 | * <code>addActionListener</code> method. |
| 39 | * <p> |
| 40 | * <b>Note:</b> To invoke an <code>ActionEvent</code> on a |
| 41 | * <code>Button</code> using the keyboard, use the Space bar. |
| 42 | * <P> |
| 43 | * The object that implements the <code>ActionListener</code> interface |
| 44 | * gets this <code>ActionEvent</code> when the event occurs. The listener |
| 45 | * is therefore spared the details of processing individual mouse movements |
| 46 | * and mouse clicks, and can instead process a "meaningful" (semantic) |
| 47 | * event like "button pressed". |
| 48 | * |
| 49 | * @see ActionListener |
| 50 | * @see <a href="http://java.sun.com/docs/books/tutorial/post1.0/ui/eventmodel.html">Tutorial: Java 1.1 Event Model</a> |
| 51 | * |
| 52 | * @author Carl Quinn |
| 53 | * @since 1.1 |
| 54 | */ |
| 55 | public class ActionEvent extends AWTEvent { |
| 56 | |
| 57 | /** |
| 58 | * The shift modifier. An indicator that the shift key was held |
| 59 | * down during the event. |
| 60 | */ |
| 61 | public static final int SHIFT_MASK = Event.SHIFT_MASK; |
| 62 | |
| 63 | /** |
| 64 | * The control modifier. An indicator that the control key was held |
| 65 | * down during the event. |
| 66 | */ |
| 67 | public static final int CTRL_MASK = Event.CTRL_MASK; |
| 68 | |
| 69 | /** |
| 70 | * The meta modifier. An indicator that the meta key was held |
| 71 | * down during the event. |
| 72 | */ |
| 73 | public static final int META_MASK = Event.META_MASK; |
| 74 | |
| 75 | /** |
| 76 | * The alt modifier. An indicator that the alt key was held |
| 77 | * down during the event. |
| 78 | */ |
| 79 | public static final int ALT_MASK = Event.ALT_MASK; |
| 80 | |
| 81 | |
| 82 | /** |
| 83 | * The first number in the range of ids used for action events. |
| 84 | */ |
| 85 | public static final int ACTION_FIRST = 1001; |
| 86 | |
| 87 | /** |
| 88 | * The last number in the range of ids used for action events. |
| 89 | */ |
| 90 | public static final int ACTION_LAST = 1001; |
| 91 | |
| 92 | /** |
| 93 | * This event id indicates that a meaningful action occured. |
| 94 | */ |
| 95 | public static final int ACTION_PERFORMED = ACTION_FIRST; //Event.ACTION_EVENT |
| 96 | |
| 97 | /** |
| 98 | * The nonlocalized string that gives more details |
| 99 | * of what actually caused the event. |
| 100 | * This information is very specific to the component |
| 101 | * that fired it. |
| 102 | |
| 103 | * @serial |
| 104 | * @see #getActionCommand |
| 105 | */ |
| 106 | String actionCommand; |
| 107 | |
| 108 | /** |
| 109 | * Timestamp of when this event occurred. Because an ActionEvent is a high- |
| 110 | * level, semantic event, the timestamp is typically the same as an |
| 111 | * underlying InputEvent. |
| 112 | * |
| 113 | * @serial |
| 114 | * @see #getWhen |
| 115 | */ |
| 116 | long when; |
| 117 | |
| 118 | /** |
| 119 | * This represents the key modifier that was selected, |
| 120 | * and is used to determine the state of the selected key. |
| 121 | * If no modifier has been selected it will default to |
| 122 | * zero. |
| 123 | * |
| 124 | * @serial |
| 125 | * @see #getModifiers |
| 126 | */ |
| 127 | int modifiers; |
| 128 | |
| 129 | /* |
| 130 | * JDK 1.1 serialVersionUID |
| 131 | */ |
| 132 | private static final long serialVersionUID = -7671078796273832149L; |
| 133 | |
| 134 | /** |
| 135 | * Constructs an <code>ActionEvent</code> object. |
| 136 | * <p> |
| 137 | * Note that passing in an invalid <code>id</code> results in |
| 138 | * unspecified behavior. This method throws an |
| 139 | * <code>IllegalArgumentException</code> if <code>source</code> |
| 140 | * is <code>null</code>. |
| 141 | * A <code>null</code> <code>command</code> string is legal, |
| 142 | * but not recommended. |
| 143 | * |
| 144 | * @param source the object that originated the event |
| 145 | * @param id an integer that identifies the event |
| 146 | * @param command a string that may specify a command (possibly one |
| 147 | * of several) associated with the event |
| 148 | * @throws IllegalArgumentException if <code>source</code> is null |
| 149 | */ |
| 150 | public ActionEvent(Object source, int id, String command) { |
| 151 | this(source, id, command, 0); |
| 152 | } |
| 153 | |
| 154 | /** |
| 155 | * Constructs an <code>ActionEvent</code> object with modifier keys. |
| 156 | * <p> |
| 157 | * Note that passing in an invalid <code>id</code> results in |
| 158 | * unspecified behavior. This method throws an |
| 159 | * <code>IllegalArgumentException</code> if <code>source</code> |
| 160 | * is <code>null</code>. |
| 161 | * A <code>null</code> <code>command</code> string is legal, |
| 162 | * but not recommended. |
| 163 | * |
| 164 | * @param source the object that originated the event |
| 165 | * @param id an integer that identifies the event |
| 166 | * @param command a string that may specify a command (possibly one |
| 167 | * of several) associated with the event |
| 168 | * @param modifiers the modifier keys held down during this action |
| 169 | * @throws IllegalArgumentException if <code>source</code> is null |
| 170 | */ |
| 171 | public ActionEvent(Object source, int id, String command, int modifiers) { |
| 172 | this(source, id, command, 0, modifiers); |
| 173 | } |
| 174 | |
| 175 | /** |
| 176 | * Constructs an <code>ActionEvent</code> object with the specified |
| 177 | * modifier keys and timestamp. |
| 178 | * <p> |
| 179 | * Note that passing in an invalid <code>id</code> results in |
| 180 | * unspecified behavior. This method throws an |
| 181 | * <code>IllegalArgumentException</code> if <code>source</code> |
| 182 | * is <code>null</code>. |
| 183 | * A <code>null</code> <code>command</code> string is legal, |
| 184 | * but not recommended. |
| 185 | * |
| 186 | * @param source the object that originated the event |
| 187 | * @param id an integer that identifies the event |
| 188 | * @param command a string that may specify a command (possibly one |
| 189 | * of several) associated with the event |
| 190 | * @param when the time the event occurred |
| 191 | * @param modifiers the modifier keys held down during this action |
| 192 | * @throws IllegalArgumentException if <code>source</code> is null |
| 193 | * |
| 194 | * @since 1.4 |
| 195 | */ |
| 196 | public ActionEvent(Object source, int id, String command, long when, |
| 197 | int modifiers) { |
| 198 | super(source, id); |
| 199 | this.actionCommand = command; |
| 200 | this.when = when; |
| 201 | this.modifiers = modifiers; |
| 202 | } |
| 203 | |
| 204 | /** |
| 205 | * Returns the command string associated with this action. |
| 206 | * This string allows a "modal" component to specify one of several |
| 207 | * commands, depending on its state. For example, a single button might |
| 208 | * toggle between "show details" and "hide details". The source object |
| 209 | * and the event would be the same in each case, but the command string |
| 210 | * would identify the intended action. |
| 211 | * <p> |
| 212 | * Note that if a <code>null</code> command string was passed |
| 213 | * to the constructor for this <code>ActionEvent</code>, this |
| 214 | * this method returns <code>null</code>. |
| 215 | * |
| 216 | * @return the string identifying the command for this event |
| 217 | */ |
| 218 | public String getActionCommand() { |
| 219 | return actionCommand; |
| 220 | } |
| 221 | |
| 222 | /** |
| 223 | * Returns the timestamp of when this event occurred. Because an |
| 224 | * ActionEvent is a high-level, semantic event, the timestamp is typically |
| 225 | * the same as an underlying InputEvent. |
| 226 | * |
| 227 | * @return this event's timestamp |
| 228 | * @since 1.4 |
| 229 | */ |
| 230 | public long getWhen() { |
| 231 | return when; |
| 232 | } |
| 233 | |
| 234 | /** |
| 235 | * Returns the modifier keys held down during this action event. |
| 236 | * |
| 237 | * @return the bitwise-or of the modifier constants |
| 238 | */ |
| 239 | public int getModifiers() { |
| 240 | return modifiers; |
| 241 | } |
| 242 | |
| 243 | /** |
| 244 | * Returns a parameter string identifying this action event. |
| 245 | * This method is useful for event-logging and for debugging. |
| 246 | * |
| 247 | * @return a string identifying the event and its associated command |
| 248 | */ |
| 249 | public String paramString() { |
| 250 | String typeStr; |
| 251 | switch(id) { |
| 252 | case ACTION_PERFORMED: |
| 253 | typeStr = "ACTION_PERFORMED"; |
| 254 | break; |
| 255 | default: |
| 256 | typeStr = "unknown type"; |
| 257 | } |
| 258 | return typeStr + ",cmd="+actionCommand+",when="+when+",modifiers="+ |
| 259 | KeyEvent.getKeyModifiersText(modifiers); |
| 260 | } |
| 261 | } |