code: public ServiceFuture<TopicSharedAccessKeysInner> regenerateKeyAsync(String resourceGroupName, String topicName, String keyName, final ServiceCallback<TopicSharedAccessKeysInner> serviceCallback) {
          return ServiceFuture.fromResponse(regenerateKeyWithServiceResponseAsync(resourceGroupName, topicName, keyName), serviceCallback);
      }
docs: Regenerate key for a topic.
  Regenerate a shared access key for a topic.
  
  @param resourceGroupName The name of the resource group within the user's subscription.
  @param topicName Name of the topic
  @param keyName Key name to regenerate key1 or key2
  @param serviceCallback the async ServiceCallback to handle successful and failed responses.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceFuture} object