libjava/java/awt/event/InputEvent.java

   1 /* InputEvent.java -- common superclass of component input events
   2    Copyright (C) 1999, 2002, 2004, 2005  Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.awt.event;
  40
  41 import gnu.java.awt.EventModifier;
  42
  43 import java.awt.Component;
  44
  45 /**
  46  * This is the common superclass for all component input classes. These are
  47  * passed to listeners before the component, so that listeners can consume
  48  * the event before it does its default behavior.
  49  *
  50  * @author Aaron M. Renn (arenn@urbanophile.com)
  51  * @see KeyEvent
  52  * @see KeyAdapter
  53  * @see MouseEvent
  54  * @see MouseAdapter
  55  * @see MouseMotionAdapter
  56  * @see MouseWheelEvent
  57  * @since 1.1
  58  * @status updated to 1.4
  59  */
  60 public abstract class InputEvent extends ComponentEvent
  61 {
  62   /**
  63    * Compatible with JDK 1.1+.
  64    */
  65   private static final long serialVersionUID = -2482525981698309786L;
  66
  67   /**
  68    * This is the bit mask which indicates the shift key is down. It is
  69    * recommended that SHIFT_DOWN_MASK be used instead.
  70    *
  71    * @see #SHIFT_DOWN_MASK
  72    */
  73   public static final int SHIFT_MASK = 1;
  74
  75   /**
  76    * This is the bit mask which indicates the control key is down. It is
  77    * recommended that CTRL_DOWN_MASK be used instead.
  78    *
  79    * @see #CTRL_DOWN_MASK
  80    */
  81   public static final int CTRL_MASK = 2;
  82
  83   /**
  84    * This is the bit mask which indicates the meta key is down. It is
  85    * recommended that META_DOWN_MASK be used instead.
  86    *
  87    * @see #META_DOWN_MASK
  88    */
  89   public static final int META_MASK = 4;
  90
  91   /**
  92    * This is the bit mask which indicates the alt key is down. It is
  93    * recommended that ALT_DOWN_MASK be used instead.
  94    *
  95    * @see #ALT_DOWN_MASK
  96    */
  97   public static final int ALT_MASK = 8;
  98
  99   /**
 100    * This is the bit mask which indicates the alt-graph modifier is in effect.
 101    * It is recommended that ALT_GRAPH_DOWN_MASK be used instead.
 102    *
 103    * @see #ALT_GRAPH_DOWN_MASK
 104    */
 105   public static final int ALT_GRAPH_MASK = 0x20;
 106
 107   /**
 108    * This bit mask indicates mouse button one is down. It is recommended that
 109    * BUTTON1_DOWN_MASK be used instead.
 110    *
 111    * @see #BUTTON1_DOWN_MASK
 112    */
 113   public static final int BUTTON1_MASK = 0x10;
 114
 115   /**
 116    * This bit mask indicates mouse button two is down. It is recommended that
 117    * BUTTON2_DOWN_MASK be used instead.
 118    *
 119    * @see #BUTTON2_DOWN_MASK
 120    */
 121   public static final int BUTTON2_MASK = 8;
 122
 123   /**
 124    * This bit mask indicates mouse button three is down. It is recommended
 125    * that BUTTON3_DOWN_MASK be used instead.
 126    *
 127    * @see #BUTTON3_DOWN_MASK
 128    */
 129   public static final int BUTTON3_MASK = 4;
 130
 131   /**
 132    * The SHIFT key extended modifier.
 133    *
 134    * @since 1.4
 135    */
 136   public static final int SHIFT_DOWN_MASK = 0x0040;
 137
 138   /**
 139    * The CTRL key extended modifier.
 140    *
 141    * @since 1.4
 142    */
 143   public static final int CTRL_DOWN_MASK = 0x0080;
 144
 145   /**
 146    * The META key extended modifier.
 147    *
 148    * @since 1.4
 149    */
 150   public static final int META_DOWN_MASK = 0x0100;
 151
 152   /**
 153    * The ALT key extended modifier.
 154    *
 155    * @since 1.4
 156    */
 157   public static final int ALT_DOWN_MASK = 0x0200;
 158
 159   /**
 160    * The mouse button1 key extended modifier.
 161    *
 162    * @since 1.4
 163    */
 164   public static final int BUTTON1_DOWN_MASK = 0x0400;
 165
 166   /**
 167    * The mouse button2 extended modifier.
 168    *
 169    * @since 1.4
 170    */
 171   public static final int BUTTON2_DOWN_MASK = 0x0800;
 172
 173   /**
 174    * The mouse button3 extended modifier.
 175    *
 176    * @since 1.4
 177    */
 178   public static final int BUTTON3_DOWN_MASK = 0x1000;
 179
 180   /**
 181    * The ALT_GRAPH key extended modifier.
 182    *
 183    * @since 1.4
 184    */
 185   public static final int ALT_GRAPH_DOWN_MASK = 0x2000;
 186
 187   /** The mask to convert new to old, package visible for use in subclasses. */
 188   static final int CONVERT_MASK
 189     = EventModifier.NEW_MASK & ~(BUTTON2_DOWN_MASK | BUTTON3_DOWN_MASK);
 190
 191   /**
 192    * The timestamp when this event occurred.
 193    *
 194    * @see #getWhen()
 195    * @serial the timestamp
 196    */
 197   private final long when;
 198
 199   /**
 200    * The modifiers in effect for this event. Package visible for use by
 201    * subclasses. The old style (bitmask 0x3f) should not be mixed with the
 202    * new style (bitmasks 0xffffffc0).
 203    *
 204    * @see #getModifiers()
 205    * @see MouseEvent
 206    * @serial the modifier state, stored in the new style
 207    */
 208   int modifiers;
 209
 210   /**
 211    * Initializes a new instance of <code>InputEvent</code> with the specified
 212    * source, id, timestamp, and modifiers. Note that an invalid id leads to
 213    * unspecified results.
 214    *
 215    * @param source the source of the event
 216    * @param id the event id
 217    * @param when the timestamp when the event occurred
 218    * @param modifiers the modifiers in effect for this event, old or new style
 219    * @throws IllegalArgumentException if source is null
 220    */
 221   InputEvent(Component source, int id, long when, int modifiers)
 222   {
 223     super(source, id);
 224     this.when = when;
 225     this.modifiers = EventModifier.extend(modifiers);
 226   }
 227
 228   /**
 229    * This method tests whether or not the shift key was down during the event.
 230    *
 231    * @return true if the shift key is down
 232    */
 233   public boolean isShiftDown()
 234   {
 235     return (modifiers & SHIFT_DOWN_MASK) != 0;
 236   }
 237
 238   /**
 239    * This method tests whether or not the control key was down during the
 240    * event.
 241    *
 242    * @return true if the control key is down
 243    */
 244   public boolean isControlDown()
 245   {
 246     return (modifiers & CTRL_DOWN_MASK) != 0;
 247   }
 248
 249   /**
 250    * This method tests whether or not the meta key was down during the event.
 251    *
 252    * @return true if the meta key is down
 253    */
 254   public boolean isMetaDown()
 255   {
 256     return (modifiers & META_DOWN_MASK) != 0;
 257   }
 258
 259   /**
 260    * This method tests whether or not the alt key was down during the event.
 261    *
 262    * @return true if the alt key is down
 263    */
 264   public boolean isAltDown()
 265   {
 266     return (modifiers & ALT_DOWN_MASK) != 0;
 267   }
 268
 269   /**
 270    * This method tests whether or not the alt-graph modifier was in effect
 271    * during the event.
 272    *
 273    * @return true if the alt-graph modifier is down
 274    */
 275   public boolean isAltGraphDown()
 276   {
 277     return (modifiers & ALT_GRAPH_DOWN_MASK) != 0;
 278   }
 279
 280   /**
 281    * This method returns the timestamp when this event occurred.
 282    *
 283    * @return the timestamp when this event occurred
 284    */
 285   public long getWhen()
 286   {
 287     return when;
 288   }
 289
 290   /**
 291    * This method returns the old-style modifiers in effect for this event.
 292    * Note that this is ambiguous between button2 and alt, and between
 293    * button3 and meta. Also, code which generated these modifiers tends to
 294    * only list the modifier that just changed, even if others were down at
 295    * the time. Consider using getModifiersEx instead. This will be a union
 296    * of the bit masks defined in this class that are applicable to the event.
 297    *
 298    * @return the modifiers in effect for this event
 299    * @see #getModifiersEx()
 300    */
 301   public int getModifiers()
 302   {
 303     return EventModifier.revert(modifiers);
 304   }
 305
 306   /**
 307    * Returns the extended modifiers (new-style) for this event. This represents
 308    * the state of all modal keys and mouse buttons at the time of the event,
 309    * and does not suffer from the problems mentioned in getModifiers.
 310    *
 311    * <p>For an example of checking multiple modifiers, this code will return
 312    * true only if SHIFT and BUTTON1 were pressed and CTRL was not:
 313    * <pre>
 314    * int onmask = InputEvent.SHIFT_DOWN_MASK | InputEvent.BUTTON1_DOWN_MASK;
 315    * int offmask = InputEvent.CTRL_DOWN_MASK;
 316    * return (event.getModifiersEx() & (onmask | offmask)) == onmask;
 317    * </pre>
 318    *
 319    * @return the bitwise or of all modifiers pressed during the event
 320    * @since 1.4
 321    */
 322   public int getModifiersEx()
 323   {
 324     return modifiers;
 325   }
 326
 327   /**
 328    * Consumes this event.  A consumed event is not processed further by the AWT
 329    * system.
 330    */
 331   public void consume()
 332   {
 333     consumed = true;
 334   }
 335
 336   /**
 337    * This method tests whether or not this event has been consumed.
 338    *
 339    * @return true if this event has been consumed
 340    */
 341   public boolean isConsumed()
 342   {
 343     return consumed;
 344   }
 345
 346   /**
 347    * Convert the extended modifier bitmask into a String, such as "Shift" or
 348    * "Ctrl+Button1".
 349    *
 350    * XXX Sun claims this can be localized via the awt.properties file - how
 351    * do we implement that?
 352    *
 353    * @param modifiers the modifiers
 354    * @return a string representation of the modifiers in this bitmask
 355    * @since 1.4
 356    */
 357   public static String getModifiersExText(int modifiers)
 358   {
 359     modifiers &= EventModifier.NEW_MASK;
 360     if (modifiers == 0)
 361       return "";
 362     StringBuffer s = new StringBuffer();
 363     if ((modifiers & META_DOWN_MASK) != 0)
 364       s.append("Meta+");
 365     if ((modifiers & CTRL_DOWN_MASK) != 0)
 366       s.append("Ctrl+");
 367     if ((modifiers & ALT_DOWN_MASK) != 0)
 368       s.append("Alt+");
 369     if ((modifiers & SHIFT_DOWN_MASK) != 0)
 370       s.append("Shift+");
 371     if ((modifiers & ALT_GRAPH_DOWN_MASK) != 0)
 372       s.append("Alt Graph+");
 373     if ((modifiers & BUTTON1_DOWN_MASK) != 0)
 374       s.append("Button1+");
 375     if ((modifiers & BUTTON2_DOWN_MASK) != 0)
 376       s.append("Button2+");
 377     if ((modifiers & BUTTON3_DOWN_MASK) != 0)
 378       s.append("Button3+");
 379     return s.substring(0, s.length() - 1);
 380   }
 381 } // class InputEvent