window.java

《移动Agent技术》一书的所有章节源代码。

        if (windowListener != null) {
            switch(e.getID()) {
              case WindowEvent.WINDOW_OPENED:
                windowListener.windowOpened(e);
                break;
              case WindowEvent.WINDOW_CLOSING:
                windowListener.windowClosing(e);
                break;
              case WindowEvent.WINDOW_CLOSED:
                windowListener.windowClosed(e);
                break;
              case WindowEvent.WINDOW_ICONIFIED:
                windowListener.windowIconified(e);
                break;
              case WindowEvent.WINDOW_DEICONIFIED:
                windowListener.windowDeiconified(e);
                break;
              case WindowEvent.WINDOW_ACTIVATED:
                windowListener.windowActivated(e);
                break;
              case WindowEvent.WINDOW_DEACTIVATED:
                windowListener.windowDeactivated(e);
                break;
              default:
                break;
            }
        }
    }

    /* Handle TAB and Shift-TAB events. */
    private boolean handleTabEvent(KeyEvent e) {
        if (e.getKeyCode() != '\t' || (e.getSource() instanceof TextArea)) {
            return false;
        }
	if ((e.getModifiers() & ~InputEvent.SHIFT_MASK) > 0) {
	    return false;
	}
        int id = e.getID();
	if (id == KeyEvent.KEY_RELEASED || id == KeyEvent.KEY_TYPED) {
	    return true;
	}
	if (e.isShiftDown()) {
	    return focusMgr.focusPrevious();
	} else {
	    return focusMgr.focusNext();
	}
    }

    void preProcessKeyEvent(KeyEvent e) {
        // Dump the list of child windows to System.out.
        if (e.isActionKey() && e.getKeyCode() == KeyEvent.VK_F1 &&
            e.isControlDown() && e.isShiftDown()) {
            list(System.out, 0);
        }
    }

    void postProcessKeyEvent(KeyEvent e) {
        if (handleTabEvent(e)) {
            e.consume();
            return;
        }
    }

    void setFocusOwner(Component c) {
	focusMgr.setFocusOwner(c);
    }

    void transferFocus(Component base) {
	nextFocus(base);
    }

    boolean isActive() {
	return active;
    }

    /**
     * Returns the child component of this Window which has focus if and
     * only if this Window is active.
     * @return the component with focus, or null if no children have focus
     * assigned to them.
     */
    public Component getFocusOwner() {
        if (active)
            return focusMgr.getFocusOwner();
        else
            return null;
    }

    /**
     * @deprecated As of JDK version 1.1,
     * replaced by <code>transferFocus(Component)</code>.
     */
    void nextFocus(Component base) {
	focusMgr.focusNext(base);
    }

    /*
     * Dispatches an event to this window or one of its sub components.
     * @param e the event
     */
    void dispatchEventImpl(AWTEvent e) {
        switch(e.getID()) {
          case FocusEvent.FOCUS_GAINED:
            setFocusOwner(this);
            break;
          case ComponentEvent.COMPONENT_RESIZED:
            invalidate();
            validate();
            repaint();
            break;

          case WindowEvent.WINDOW_ACTIVATED:
            active = true;
/*
  Calling this messes up focus on Solaris

            focusMgr.activateFocus();
*/
            break;

          case WindowEvent.WINDOW_DEACTIVATED:
            active = false;
            break;

          default:
            break;
        }
        super.dispatchEventImpl(e);
    }

    /**
     * @deprecated As of JDK version 1.1
     * replaced by <code>dispatchEvent(AWTEvent)</code>.
     */
    public boolean postEvent(Event e) {
        if (handleEvent(e)) {
            e.consume();
            return true;
        }
        return false;
    }

    /**
     * Checks if this Window is showing on screen.
     * @see java.awt.Component#setVisible(boolean)
     */
    public boolean isShowing() {
	return visible;
    }

    /* Serialization support.  If there's a MenuBar we restore
     * its (transient) parent field here.
     */

    private int windowSerializedDataVersion = 1;


    private void writeObject(ObjectOutputStream s)
      throws IOException
    {
      s.defaultWriteObject();

      AWTEventMulticaster.save(s, windowListenerK, windowListener);
      s.writeObject(null);
    }


    private void readObject(ObjectInputStream s)
      throws ClassNotFoundException, IOException
    {
      s.defaultReadObject();

      Object keyOrNull;
      while(null != (keyOrNull = s.readObject())) {
	String key = ((String)keyOrNull).intern();

	if (windowListenerK == key)
	  addWindowListener((WindowListener)(s.readObject()));

	else // skip value for unrecognized key
	  s.readObject();
      }
      setWarningString();
    }

}


class FocusManager implements java.io.Serializable {
    Container focusRoot;
    Component focusOwner; //Bug #4101153 : a backout for b fix made for
							//bug # 4092347

    /*
     * JDK 1.1 serialVersionUID
     */
    static final long serialVersionUID = 2491878825643557906L;

    FocusManager(Container cont) {
	focusRoot = cont;
    }

    /* Re-activate the last component with focus if it is still
     * visible and active.
     * If no component had focus yet, assign it to first component
     * capable of receiving it (visible, active, focusable).
     * If no visible, active, focusable components are present,
     * assign focus to the focus root.
     */
    void activateFocus() {
        boolean assigned = false;
        if (focusOwner != null) {
            if ((assigned = assignFocus(focusOwner, false)) != true) {
                assigned = focusNext(focusOwner);
            }
        } else {
            // assign to first component capable of taking it
            assigned = focusForward(focusRoot);
        }
        if (!assigned) {
            focusRoot.requestFocus();
        }
    }


    synchronized void setFocusOwner(Component c) {
        focusOwner = c;
    }

    Component getFocusOwner() {
       return focusOwner;
    }

    boolean focusNext() {
       return focusNext(focusOwner);
    }

    boolean focusNext(Component base) {
        synchronized (focusRoot.getTreeLock()) { // BUGID4067845
            Component target = base;
            if (target != null && target.parent != null) {
                //System.out.println("FocusManager.focusNext: owner="+focusOwner);
                do {
                    boolean found = false;
                    Container p = target.parent;
                    Component c;
                    for (int i = 0; i < p.ncomponents; i++) {
                        c = p.component[i];
                        if (found) {
                            if (assignFocus(c)) {
                                return true;
                            }
                            if (c instanceof Container &&
                        			c.isVisible() &&
                        			c.isEnabled()) {
                                if (focusForward((Container)c)) {
                                    return true;
                                }
                            }
                        } else if (c == target) {
                            found = true;
                        }
                    }
                    target = p;
                } while (target != focusRoot && target.parent != null);
    		}
            // wrap-around
            if (focusForward(focusRoot)) {
                return true;
            }

            return false;
        }
    }


    boolean focusPrevious() {
        return focusPrevious(focusOwner);
    }

    boolean focusPrevious(Component base) {
        synchronized (focusRoot.getTreeLock()) { // BUGID4067845
            Component target = base;
            if (target != null && target.parent != null) {
                do {
                    boolean found = false;
                    Container p = target.parent;
                        Component c;
                    for (int i = p.ncomponents-1; i >= 0; i--) {
                        c = p.component[i];
                        if (found) {
                            if (assignFocus(c)) {
                                return true;
                            }
                            if (c instanceof Container &&
                            		c.isVisible() &&
                            		c.isEnabled()) {
                                if (focusBackward((Container)c)) {
                                    return true;
                                }
                             }
                         } else if (c == target) {
                             found = true;
                         }
                    }
                    target = p;
                } while (target != focusRoot);

            }
                            // wrap-around
            if (focusBackward(focusRoot)) {
                return true;
            }
            return false;
        }
    }

    boolean assignFocus(Component c) {
        return assignFocus(c, true);
    }

    synchronized boolean assignFocus(Component c, boolean requireTraversable) {
        if (c.isVisible() && c.isEnabled() &&
            (!requireTraversable || c.isFocusTraversable())) {
            //System.out.println("FocusManager.assignFocus: "+c);
            c.requestFocus();
            return true;
        }
        return false;
    }

    synchronized boolean focusForward(Container cont) {
        for (int i = 0; i < cont.ncomponents; i++) {
            Component c = cont.component[i];
            if (assignFocus(c)) {
                return true;
            }
            if (c instanceof Container && c.isVisible() && c.isEnabled()) {
                if (focusForward((Container)c)) {
                    return true;
                }
            }
        }
        return false;
    }

    synchronized boolean focusBackward(Container cont) {
        for (int i = cont.ncomponents-1; i >= 0; i--) {
            Component c = cont.component[i];
            if (assignFocus(c)) {
                return true;
            }
            if (c instanceof Container && c.isVisible() && c.isEnabled()) {
                if (focusBackward((Container)c)) {
                    return true;
                }
            }
        }
        return false;
    }

}