public void handleSend(HttpServerResponse response, Span span) {
    handleFinish(response, span);
  }
@Test void handleSend_oneOfResponseError() {
    brave.Span span = mock(brave.Span.class);

    assertThatThrownBy(() -> handler.handleSend(null, span))
      .isInstanceOf(NullPointerException.class)
      .hasMessage("response == null");
  }