I determined that the browser bar was located at 0. So I check if my Y position is less than 0 then call .setPagePosition
.
this.addListener(new PanelListenerAdapter()
{
@Override
public void onMove(BoxComponent component, int x, int y)
{
// prevent user from accidentally dragging window under browser bar
if (y <= 0)
{
component.setPagePosition(DEFAULT_X_POS, DEFAULT_Y_POS);
}
}
});