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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package sun.awt;

import java.awt.Component;
import java.awt.Container;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.MenuBar;
import java.awt.MenuComponent;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.dnd.DragGestureEvent;
import java.awt.dnd.DragGestureListener;
import java.awt.dnd.DragGestureRecognizer;
import java.awt.dnd.DragSource;
import java.awt.dnd.DropTarget;
import java.awt.dnd.InvalidDnDOperationException;
import java.awt.dnd.peer.DragSourceContextPeer;
import java.awt.peer.FramePeer;

The class provides basic functionality for a lightweight frame
implementation. A subclass is expected to provide painting to an
offscreen image and access to it. Thus it can be used for lightweight
embedding.
Author:
Artem Ananiev, Anton Tarasov/**
 * The class provides basic functionality for a lightweight frame
 * implementation. A subclass is expected to provide painting to an
 * offscreen image and access to it. Thus it can be used for lightweight
 * embedding.
 *
 * @author Artem Ananiev
 * @author Anton Tarasov
 */
@SuppressWarnings("serial")
public abstract class LightweightFrame extends Frame {

    
Constructs a new, initially invisible LightweightFrame instance. /**
     * Constructs a new, initially invisible {@code LightweightFrame}
     * instance.
     */
    public LightweightFrame() {
        setUndecorated(true);
        setResizable(true);
        setEnabled(true);
    }

    
Blocks introspection of a parent window by this child.
Returns:
null/**
     * Blocks introspection of a parent window by this child.
     *
     * @return null
     */
    @Override public final Container getParent() { return null; }

    @Override public Graphics getGraphics() { return null; }

    @Override public final boolean isResizable() { return true; }

    // Block modification of any frame attributes, since they aren't
    // applicable for a lightweight frame.

    @Override public final void setTitle(String title) {}
    @Override public final void setIconImage(Image image) {}
    @Override public final void setIconImages(java.util.List<? extends Image> icons) {}
    @Override public final void setMenuBar(MenuBar mb) {}
    @Override public final void setResizable(boolean resizable) {}
    @Override public final void remove(MenuComponent m) {}
    @Override public final void toFront() {}
    @Override public final void toBack() {}

    @Override public void addNotify() {
        synchronized (getTreeLock()) {
            if (getPeer() == null) {
                SunToolkit stk = (SunToolkit)Toolkit.getDefaultToolkit();
                try {
                    setPeer(stk.createLightweightFrame(this));
                } catch (Exception e) {
                    throw new RuntimeException(e);
                }
            }
            super.addNotify();
        }
    }

    private void setPeer(final FramePeer p) {
        AWTAccessor.getComponentAccessor().setPeer(this, p);
    }

    
Requests the peer to emulate activation or deactivation of the
frame. Peers should override this method if they are to implement
this functionality.
Params:
activate – if true, activates the frame;
                otherwise, deactivates the frame/**
     * Requests the peer to emulate activation or deactivation of the
     * frame. Peers should override this method if they are to implement
     * this functionality.
     *
     * @param activate if <code>true</code>, activates the frame;
     *                 otherwise, deactivates the frame
     */
    public void emulateActivation(boolean activate) {
        ((FramePeer)getPeer()).emulateActivation(activate);
    }

    
Delegates the focus grab action to the client (embedding) application.
The method is called by the AWT grab machinery.
See Also:
grab.grab(Window)/**
     * Delegates the focus grab action to the client (embedding) application.
     * The method is called by the AWT grab machinery.
     *
     * @see SunToolkit#grab(java.awt.Window)
     */
    public abstract void grabFocus();

    
Delegates the focus ungrab action to the client (embedding) application.
The method is called by the AWT grab machinery.
See Also:
ungrab.ungrab(Window)/**
     * Delegates the focus ungrab action to the client (embedding) application.
     * The method is called by the AWT grab machinery.
     *
     * @see SunToolkit#ungrab(java.awt.Window)
     */
    public abstract void ungrabFocus();

    
Returns the scale factor of this frame. The default value is 1.
See Also:
notifyDisplayChanged(int)
Returns:
the scale factor/**
     * Returns the scale factor of this frame. The default value is 1.
     *
     * @return the scale factor
     * @see #notifyDisplayChanged(int)
     */
    public abstract int getScaleFactor();

    
Called when display of the hosted frame is changed.
Params:
scaleFactor – the scale factor/**
     * Called when display of the hosted frame is changed.
     *
     * @param scaleFactor the scale factor
     */
    public abstract void notifyDisplayChanged(int scaleFactor);

    
Host window absolute bounds.
/**
     * Host window absolute bounds.
     */
    private int hostX, hostY, hostW, hostH;

    
Returns the absolute bounds of the host (embedding) window.
Returns:
the host window bounds/**
     * Returns the absolute bounds of the host (embedding) window.
     *
     * @return the host window bounds
     */
    public Rectangle getHostBounds() {
        if (hostX == 0 && hostY == 0 && hostW == 0 && hostH == 0) {
            // The client app is probably unaware of the setHostBounds.
            // A safe fall-back:
            return getBounds();
        }
        return new Rectangle(hostX, hostY, hostW, hostH);
    }

    
Sets the absolute bounds of the host (embedding) window.
/**
     * Sets the absolute bounds of the host (embedding) window.
     */
    public void setHostBounds(int x, int y, int w, int h) {
        hostX = x;
        hostY = y;
        hostW = w;
        hostH = h;
    }

    
Create a drag gesture recognizer for the lightweight frame.
/**
     * Create a drag gesture recognizer for the lightweight frame.
     */
    public abstract <T extends DragGestureRecognizer> T createDragGestureRecognizer(
            Class<T> abstractRecognizerClass,
            DragSource ds, Component c, int srcActions,
            DragGestureListener dgl);

    
Create a drag source context peer for the lightweight frame.
/**
     * Create a drag source context peer for the lightweight frame.
     */
    public abstract DragSourceContextPeer createDragSourceContextPeer(DragGestureEvent dge) throws InvalidDnDOperationException;

    
Adds a drop target to the lightweight frame.
/**
     * Adds a drop target to the lightweight frame.
     */
    public abstract void addDropTarget(DropTarget dt);

    
Removes a drop target from the lightweight frame.
/**
     * Removes a drop target from the lightweight frame.
     */
    public abstract void removeDropTarget(DropTarget dt);
}