@Test public void trySample_dispatches() {

  HttpSampler sampler = new HttpSampler() {
    @Override public <Req> Boolean trySample(HttpAdapter<Req, ?> adapter, Req req) {
      return adapter.method(req).equals("POST");
    }
  };
  when(httpClientRequest.method()).thenReturn("POST");
  assertThat(sampler.trySample(httpClientRequest)).isTrue();
  verify(httpClientRequest).method();
  when(httpServerRequest.method()).thenReturn("POST");
  assertThat(sampler.trySample(httpServerRequest)).isTrue();
  verify(httpServerRequest).method();
}