import java.awt.*;

public class DBFrame extends Frame {

    private Image offScreenBuffer;
    private boolean clearFlag = true;
    
    public boolean getClearFlag() { return clearFlag;}
    public void setClearFlag(boolean flag) { clearFlag = flag;}

    public void update(Graphics g)
    {
	Graphics gr; 
	// Will hold the graphics context from the offScreenBuffer.
	// We need to make sure we keep our offscreen buffer the same size
	// as the graphics context we're working with.
	if (offScreenBuffer==null ||
	    (! (offScreenBuffer.getWidth(this) == getSize().width
                && offScreenBuffer.getHeight(this) == getSize().height)))
	    {
		offScreenBuffer = createImage(getSize().width, getSize().height);
	    }

	// We need to use our buffer Image as a Graphics object:
	gr = offScreenBuffer.getGraphics();

	// clear old graphics
	if (clearFlag) gr.clearRect(0,0,getSize().width, getSize().height);

	paint(gr); // Passes our off-screen buffer to our paint method, which,
	// unsuspecting, paints on it 
	g.drawImage(offScreenBuffer, 0, 0, this);
	// And now we transfer the info in the buffer onto the
	// graphics context
	    }
}