### Question:
FluxConnectionOptions { @Nonnull public static FluxConnectionOptions.Builder builder() { return new FluxConnectionOptions.Builder(); } private  FluxConnectionOptions(@Nonnull final Builder builder); @Nonnull static FluxConnectionOptions.Builder builder(); static Builder builder(final String connectionString); @Nonnull String getUrl(); @Nonnull OkHttpClient.Builder getOkHttpClient(); Map<String, String> getParameters();  }### Answer:
@Test void urlRequired() { FluxConnectionOptions.Builder fluxConnectionOptions = FluxConnectionOptions.builder(); Assertions.assertThatThrownBy(fluxConnectionOptions::build) .isInstanceOf(IllegalStateException.class) .hasMessage("The url to connect to Flux has to be defined."); }