code: static Rectangle2D convertRectangle(
          Component sourceComponent, 
          Rectangle2D rectangle,
          Component targetComponent)
      {
          return SwingUtilities.convertRectangle(
              sourceComponent, asRectangle(rectangle), targetComponent);        
      }
docs: Wrapper for <code>SwingUtilities#convertRectangle</code> that accepts
  a Rectangle2D and not only a Rectangle. (The Rectangle2D is internally
  converted to a Rectangle by casting all components to <code>int</code>)
  
  @param sourceComponent The source component
  @param rectangle The rectangle
  @param targetComponent The target component
  @return The new rectangle