keyevent.java

JAVA基本类源代码,大家可以学习学习!

     */
    public static final int KEY_LOCATION_STANDARD = 1;

    /**
     * A constant indicating that the key pressed or released is in
     * the left key location (there is more than one possible location
     * for this key).  Example: the left shift key.
     * @since 1.4
     */
    public static final int KEY_LOCATION_LEFT     = 2;

    /**
     * A constant indicating that the key pressed or released is in
     * the right key location (there is more than one possible location
     * for this key).  Example: the right shift key.
     * @since 1.4
     */
    public static final int KEY_LOCATION_RIGHT    = 3;

    /**
     * A constant indicating that the key event originated on the
     * numeric keypad or with a virtual key corresponding to the
     * numeric keypad.
     * @since 1.4
     */
    public static final int KEY_LOCATION_NUMPAD   = 4;

    /**
     * The unique value assigned to each of the keys on the
     * keyboard.  There is a common set of key codes that
     * can be fired by most keyboards.
     * The symbolic name for a key code should be used rather
     * than the code value itself.
     *
     * @serial
     * @see #getKeyCode()
     * @see #setKeyCode(int)
     */
    int  keyCode;

    /**
     * <code>keyChar</code> is a valid unicode character
     * that is fired by a key or a key combination on
     * a keyboard.
     *
     * @serial
     * @see #getKeyChar()
     * @see #setKeyChar(char)
     */
    char keyChar;

    /**
     * The location of the key on the keyboard.
     *
     * Some keys occur more than once on a keyboard, e.g. the left and
     * right shift keys.  Additionally, some keys occur on the numeric
     * keypad.  This variable is used to distinguish such keys.
     *
     * The only legal values are <code>KEY_LOCATION_UNKNOWN</code>, 
     * <code>KEY_LOCATION_STANDARD</code>, <code>KEY_LOCATION_LEFT</code>, 
     * <code>KEY_LOCATION_RIGHT</code>, and <code>KEY_LOCATION_NUMPAD</code>.
     *
     * @serial
     * @see #getKeyLocation()
     */
    int keyLocation;

    /*
     * JDK 1.1 serialVersionUID 
     */
    private static final long serialVersionUID = -2352130953028126954L;

    static {
        /* ensure that the necessary native libraries are loaded */
	NativeLibLoader.loadLibraries();
        if (!GraphicsEnvironment.isHeadless()) {
            initIDs();
        }
    }

    /**
     * Initialize JNI field and method IDs for fields that may be
     * accessed from C.
     */
    private static native void initIDs();

    /**
     * Constructs a <code>KeyEvent</code> object.
     * <p>Note that passing in an invalid <code>id</code> results in
     * unspecified behavior.
     *
     * @param source    the <code>Component</code> that originated the event
     * @param id        an integer identifying the type of event
     * @param when      a long integer that specifies the time the event
     *                  occurred
     * @param modifiers the modifier keys down during event (shift, ctrl,
     *                  alt, meta)
     *                  Either extended _DOWN_MASK or old _MASK modifiers
     *                  should be used, but both models should not be mixed
     *                  in one event. Use of the extended modifiers is
     *                  preferred.
     * @param keyCode   the integer code for an actual key, or VK_UNDEFINED
     *                  (for a key-typed event)
     * @param keyChar   the Unicode character generated by this event, or
     *                  CHAR_UNDEFINED (for key-pressed and key-released
     *                  events which do not map to a valid Unicode character)
     * @param keyLocation  identifies the key location.  The only legal
     *        values are <code>KEY_LOCATION_UNKNOWN</code>, 
     *        <code>KEY_LOCATION_STANDARD</code>, <code>KEY_LOCATION_LEFT</code>, 
     *        <code>KEY_LOCATION_RIGHT</code>, and <code>KEY_LOCATION_NUMPAD</code>.
     * @exception IllegalArgumentException  
     *     if <code>id</code> is <code>KEY_TYPED</code> and 
     *       <code>keyChar</code> is <code>CHAR_UNDEFINED</code>; 
     *     or if <code>id</code> is <code>KEY_TYPED</code> and 
     *       <code>keyCode</code> is not <code>VK_UNDEFINED</code>; 
     *     or if <code>id</code> is <code>KEY_TYPED</code> and
     *       <code>keyLocation</code> is not <code>KEY_LOCATION_UNKNOWN</code>;
     *     or if <code>keyLocation</code> is not one of the legal 
     *       values enumerated above.  
     * @since 1.4
     */
    private KeyEvent(Component source, int id, long when, int modifiers,
                    int keyCode, char keyChar, int keyLocation, boolean isProxyActive) {
        this(source, id, when, modifiers, keyCode, keyChar, keyLocation);
        this.isProxyActive = isProxyActive;
    }
    public KeyEvent(Component source, int id, long when, int modifiers,
                    int keyCode, char keyChar, int keyLocation) {
        super(source, id, when, modifiers);
        if (id == KEY_TYPED) {
            if (keyChar == CHAR_UNDEFINED) {
                throw new IllegalArgumentException("invalid keyChar");
            }
            if (keyCode != VK_UNDEFINED) {
                throw new IllegalArgumentException("invalid keyCode");
            }
            if (keyLocation != KEY_LOCATION_UNKNOWN) {
                throw new IllegalArgumentException("invalid keyLocation");
            }
        }

        this.keyCode = keyCode;
        this.keyChar = keyChar;

        if ((keyLocation < KEY_LOCATION_UNKNOWN) ||
            (keyLocation > KEY_LOCATION_NUMPAD)) {
            throw new IllegalArgumentException("invalid keyLocation");
        }
        this.keyLocation = keyLocation;
        if ((getModifiers() != 0) && (getModifiersEx() == 0)) {
	    setNewModifiers();    
	} else if ((getModifiers() == 0) && (getModifiersEx() != 0)) {
	    setOldModifiers();
	}
    }

    /**
     * Constructs a <code>KeyEvent</code> object.
     * <p>Note that passing in an invalid <code>id</code> results in
     * unspecified behavior.
     *
     * @param source    the <code>Component</code> that originated the event
     * @param id        an integer identifying the type of event
     * @param when      a long integer that specifies the time the event
     *                  occurred
     * @param modifiers the modifier keys down during event (shift, ctrl,
     *                  alt, meta)
     *                  Either extended _DOWN_MASK or old _MASK modifiers
     *                  should be used, but both models should not be mixed
     *                  in one event. Use of the extended modifiers is
     *                  preferred.
     * @param keyCode   the integer code for an actual key, or VK_UNDEFINED 
     *                  (for a key-typed event)
     * @param keyChar   the Unicode character generated by this event, or 
     *                  CHAR_UNDEFINED (for key-pressed and key-released
     *                  events which do not map to a valid Unicode character)
     * @exception IllegalArgumentException  if <code>id</code> is
     *     <code>KEY_TYPED</code> and <code>keyChar</code> is
     *     <code>CHAR_UNDEFINED</code>; or if <code>id</code> is
     *     <code>KEY_TYPED</code> and <code>keyCode</code> is not
     *     <code>VK_UNDEFINED</code>
     */
    public KeyEvent(Component source, int id, long when, int modifiers,
                    int keyCode, char keyChar) {
        this(source, id, when, modifiers, keyCode, keyChar,
          KEY_LOCATION_UNKNOWN);
    }

    /**
     * @deprecated as of JDK1.1 
     */
    public KeyEvent(Component source, int id, long when, int modifiers,
                    int keyCode) {
        this(source, id, when, modifiers, keyCode, (char)keyCode);
    }

    /**
     * Returns the integer keyCode associated with the key in this event.
     * 
     * @return the integer code for an actual key on the keyboard. 
     *         (For <code>KEY_TYPED</code> events, the keyCode is 
     *         <code>VK_UNDEFINED</code>.)
     */
    public int getKeyCode() {
        return keyCode;
    }

    /**
     * Set the keyCode value to indicate a physical key.
     *
     * @param keyCode an integer corresponding to an actual key on the keyboard.
     */
    public void setKeyCode(int keyCode) {
        this.keyCode = keyCode;
    }

    /**
     * Returns the character associated with the key in this event.
     * For example, the key-typed event for shift + "a" returns the 
     * value for "A".
     *
     * @return the Unicode character defined for this key event.
     *         If no valid Unicode character exists for this key event, 
     *         keyChar is <code>CHAR_UNDEFINED</code>.
     */
    public char getKeyChar() {
        return keyChar;
    }

    /**
     * Set the keyChar value to indicate a logical character.
     *
     * @param keyChar a char corresponding to to the combination of keystrokes
     *                that make up this event.
     */
    public void setKeyChar(char keyChar) {
        this.keyChar = keyChar;
    }

    /**
     * Set the modifiers to indicate additional keys that were held down
     * (e.g. shift, ctrl, alt, meta) defined as part of InputEvent.
     * <p>
     * NOTE:  use of this method is not recommended, because many AWT
     * implementations do not recognize modifier changes.  This is
     * especially true for <code>KEY_TYPED</code> events where the shift 
     * modifier is changed.
     *
     * @param modifiers an integer combination of the modifier constants.
     * @see InputEvent
     * @deprecated as of JDK1.1.4
     */
    public void setModifiers(int modifiers) {
        this.modifiers = modifiers;
        if ((getModifiers() != 0) && (getModifiersEx() == 0)) {
	    setNewModifiers();    
	} else if ((getModifiers() == 0) && (getModifiersEx() != 0)) {
	    setOldModifiers();
	}
    }

    /**
     * Returns the location of the key that originated this key event.
     *
     * Some keys occur more than once on a keyboard, e.g. the left and
     * right shift keys.  Additionally, some keys occur on the numeric
     * keypad.  This provides a way of distinguishing such keys.
     *
     * @return the location of the key that was pressed or released.
     *         Always returns <code>KEY_LOCATION_UNKNOWN</code> for 
     *         <code>KEY_TYPED</code> events.
     * @since 1.4
     */
    public int getKeyLocation() {
        return keyLocation;
    }

    /**
     * Returns a String describing the keyCode, such as "HOME", "F1" or "A".
     * These strings can be localized by changing the awt.properties file.
     *
     * @return a string containing a text description for a physical key,
     *         identified by its keyCode
     */
    public static String getKeyText(int keyCode) {
        if (keyCode >= VK_0 && keyCode <= VK_9 || 
            keyCode >= VK_A && keyCode <= VK_Z) {
            return String.valueOf((char)keyCode);
        }

        // Check for other ASCII keyCodes.
        int index = ",./;=[\\]".indexOf(keyCode);
        if (index >= 0) {
            return String.valueOf((char)keyCode);
        }
	
        switch(keyCode) {
          case VK_ENTER: return Toolkit.getProperty("AWT.enter", "Enter");
          case VK_BACK_SPACE: return Toolkit.getProperty("AWT.backSpace", "Backspace");
          case VK_TAB: return Toolkit.getProperty("AWT.tab", "Tab");
          case VK_CANCEL: return Toolkit.getProperty("AWT.cancel", "Cancel");
          case VK_CLEAR: return Toolkit.getProperty("AWT.clear", "Clear");
          case VK_SHIFT: return Toolkit.getProperty("AWT.shift", "Shift");
          case VK_CONTROL: return Toolkit.getProperty("AWT.control", "Control");
          case VK_ALT: return Toolkit.getProperty("AWT.alt", "Alt");
          case VK_PAUSE: return Toolkit.getProperty("AWT.pause", "Pause");
          case VK_CAPS_LOCK: return Toolkit.getProperty("AWT.capsLock", "Caps Lock");
          case VK_ESCAPE: return Toolkit.getProperty("AWT.escape", "Escape");
          case VK_SPACE: return Toolkit.getProperty("AWT.space", "Space");
          case VK_PAGE_UP: return Toolkit.getProperty("AWT.pgup", "Page Up");
          case VK_PAGE_DOWN: return Toolkit.getProperty("AWT.pgdn", "Page Down");
          case VK_END: return Toolkit.getProperty("AWT.end", "End");
          case VK_HOME: return Toolkit.getProperty("AWT.home", "Home");
          case VK_LEFT: return Toolkit.getProperty("AWT.left", "Left");
          case VK_UP: return Toolkit.getProperty("AWT.up", "Up");
          case VK_RIGHT: return Toolkit.getProperty("AWT.right", "Right");
          case VK_DOWN: return Toolkit.getProperty("AWT.down", "Down");
          // handled by ASCII value above:
          //   comma, period, slash, 0-9, semicolon, equals, A-Z,
          //   open_bracket, back_slash, close_bracket

          // numpad numeric keys handled below
          case VK_MULTIPLY: return Toolkit.getProperty("AWT.multiply", "NumPad *");
          case VK_ADD: return Toolkit.getProperty("AWT.add", "NumPad +");
          case VK_SEPARATOR: return Toolkit.getProperty("AWT.separator", "NumPad ,");
          case VK_SUBTRACT: return Toolkit.getProperty("AWT.subtract", "NumPad -");
          case VK_DECIMAL: return Toolkit.getProperty("AWT.decimal", "NumPad .");
          case VK_DIVIDE: return Toolkit.getProperty("AWT.divide", "NumPad /");
          case VK_DELETE: return Toolkit.getProperty("AWT.delete", "Delete");
          case VK_NUM_LOCK: return Toolkit.getProperty("AWT.numLock", "Num Lock");
          case VK_SCROLL_LOCK: return Toolkit.getProperty("AWT.scrollLock", "Scroll Lock");

          case VK_F1: return Toolkit.getProperty("AWT.f1", "F1");
          case VK_F2: return Toolkit.getProperty("AWT.f2", "F2");
          case VK_F3: return Toolkit.getProperty("AWT.f3", "F3");
          case VK_F4: return Toolkit.getProperty("AWT.f4", "F4");
          case VK_F5: return Toolkit.getProperty("AWT.f5", "F5");
          case VK_F6: return Toolkit.getProperty("AWT.f6", "F6");
          case VK_F7: return Toolkit.getProperty("AWT.f7", "F7");
          case VK_F8: return Toolkit.getProperty("AWT.f8", "F8");
          case VK_F9: return Toolkit.getProperty("AWT.f9", "F9");
          case VK_F10: return Toolkit.getProperty("AWT.f10", "F10");
          case VK_F11: return Toolkit.getProperty("AWT.f11", "F11");
          case VK_F12: return Toolkit.getProperty("AWT.f12", "F12");
          case VK_F13: return Toolkit.getProperty("AWT.f13", "F13");
          case VK_F14: return Toolkit.getProperty("AWT.f14", "F14");
          case VK_F15: return Toolkit.getProperty("AWT.f15", "F15");
          case VK_F16: return Toolkit.getProperty("AWT.f16", "F16");
          case VK_F17: return Toolkit.getProperty("AWT.f17", "F17");
          case VK_F18: return Toolkit.getProperty("AWT.f18", "F18");
          case VK_F19: return Toolkit.getProperty("AWT.f19", "F19");
          case VK_F20: return Toolkit.getProperty("AWT.f20", "F20");
          case VK_F21: return Toolkit.getProperty("AWT.f21", "F21");
          case VK_F22: return Toolkit.getProperty("AWT.f22", "F22");
          case VK_F23: return Toolkit.getProperty("AWT.f23", "F23");
          case VK_F24: return Toolkit.getProperty("AWT.f24", "F24");

          case VK_PRINTSCREEN: return Toolkit.getProperty("AWT.printScreen", "Print Screen");
          case VK_INSERT: return Toolkit.getProperty("AWT.insert", "Insert");
          case VK_HELP: return Toolkit.getProperty("AWT.help", "Help");
          case VK_META: return Toolkit.getProperty("AWT.meta", "Meta");
          case VK_BACK_QUOTE: return Toolkit.getProperty("AWT.backQuote", "Back Quote");
          case VK_QUOTE: return Toolkit.getProperty("AWT.quote", "Quote");
			 
          case VK_KP_UP: return Toolkit.getProperty("AWT.up", "Up");
          case VK_KP_DOWN: return Toolkit.getProperty("AWT.down", "Down");
          case VK_KP_LEFT: return Toolkit.getProperty("AWT.left", "Left");
          case VK_KP_RIGHT: return Toolkit.getProperty("AWT.right", "Right");

          case VK_DEAD_GRAVE: return Toolkit.getProperty("AWT.deadGrave", "Dead Grave");