code: public Observable<ServiceResponse<OperationStatus>> deleteRegexEntityRoleWithServiceResponseAsync(UUID appId, String versionId, UUID entityId, UUID roleId) {
          if (this.client.endpoint() == null) {
              throw new IllegalArgumentException("Parameter this.client.endpoint() is required and cannot be null.");
          }
          if (appId == null) {
              throw new IllegalArgumentException("Parameter appId is required and cannot be null.");
          }
          if (versionId == null) {
              throw new IllegalArgumentException("Parameter versionId is required and cannot be null.");
          }
          if (entityId == null) {
              throw new IllegalArgumentException("Parameter entityId is required and cannot be null.");
          }
          if (roleId == null) {
              throw new IllegalArgumentException("Parameter roleId is required and cannot be null.");
          }
          String parameterizedHost = Joiner.on(", ").join("{Endpoint}", this.client.endpoint());
          return service.deleteRegexEntityRole(appId, versionId, entityId, roleId, this.client.acceptLanguage(), parameterizedHost, this.client.userAgent())
              .flatMap(new Func1<Response<ResponseBody>, Observable<ServiceResponse<OperationStatus>>>() {
                  @Override
                  public Observable<ServiceResponse<OperationStatus>> call(Response<ResponseBody> response) {
                      try {
                          ServiceResponse<OperationStatus> clientResponse = deleteRegexEntityRoleDelegate(response);
                          return Observable.just(clientResponse);
                      } catch (Throwable t) {
                          return Observable.error(t);
                      }
                  }
              });
      }
docs: Delete an entity role.
  
  @param appId The application ID.
  @param versionId The version ID.
  @param entityId The entity ID.
  @param roleId The entity role Id.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the OperationStatus object