@Override
  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object o) {
    Object span = request.getAttribute(SpanCustomizer.class.getName());
    if (span instanceof SpanCustomizer) handlerParser.preHandle(request, o, (SpanCustomizer) span);
    return true;
  }
@Test void preHandle_parses() {
    when(request.getAttribute("brave.SpanCustomizer")).thenReturn(span);

    interceptor.preHandle(request, response, controller);

    verify(request).getAttribute("brave.SpanCustomizer");
    verify(parser).preHandle(request, controller, span);

    verifyNoMoreInteractions(request, response, parser, span);
  }