code: public String getSVGElement(String id) {
          return getSVGElement(id, true, null, null, null);
      }
docs: Returns the SVG element that has been generated by calls to this
  {@code Graphics2D} implementation, giving it the specified {@code id}.
  If {@code id} is {@code null}, the element will have no {@code id}
  attribute.
  
  @param id  the element id ({@code null} permitted).
  
  @return A string containing the SVG element.
  
  @since 1.8