@Test
public void testInvalidIssuerValueException_invalidAudience() throws Exception {

  @Api(
      issuers = {@ApiIssuer(name = "issuer", issuer = "iss")},
      issuerAudiences = {@ApiIssuerAudience(name = "issuer", audiences = {""})})
  final class Endpoint { }
  ApiConfig config = configLoader.loadConfiguration(ServiceContext.create(), Endpoint.class);
  try {
    validator.validate(config);
  } catch (InvalidIssuerValueException.ForApi e) {
    assertThat(e.getMessage()).contains("issuer 'issuer' cannot have null or blank audiences");
  }
}