code: public Observable<Boolean> checkExistenceAsync(String resourceGroupName, String resourceProviderNamespace, String parentResourcePath, String resourceType, String resourceName, String apiVersion) {
          return checkExistenceWithServiceResponseAsync(resourceGroupName, resourceProviderNamespace, parentResourcePath, resourceType, resourceName, apiVersion).map(new Func1<ServiceResponse<Boolean>, Boolean>() {
              @Override
              public Boolean call(ServiceResponse<Boolean> response) {
                  return response.body();
              }
          });
      }
docs: Checks whether a resource exists.
  
  @param resourceGroupName The name of the resource group containing the resource to check. The name is case insensitive.
  @param resourceProviderNamespace The resource provider of the resource to check.
  @param parentResourcePath The parent resource identity.
  @param resourceType The resource type.
  @param resourceName The name of the resource to check whether it exists.
  @param apiVersion The API version to use for the operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the Boolean object