arpadboda commented on a change in pull request #489: MINIFICPP-740: Add ability to run NiFi processors from Java and Python URL: https://github.com/apache/nifi-minifi-cpp/pull/489#discussion_r260262266
########## File path: libminifi/include/core/WeakReference.h ########## @@ -0,0 +1,103 @@ +/** + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef LIBMINIFI_INCLUDE_CORE_WEAKREFERENCE_H_ +#define LIBMINIFI_INCLUDE_CORE_WEAKREFERENCE_H_ + +#include <type_traits> +#include <vector> + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace core { + +/* + * An homage to weak references in java, this acts as a class + * which can be used to remove referenced classes when needed. + */ +class WeakReference { + public: + + WeakReference(const WeakReference &other) = delete; + WeakReference(WeakReference &&other) = default; + WeakReference &operator=(const WeakReference &other) = delete; + WeakReference &operator=(WeakReference &&other) = default; + + virtual ~WeakReference() { + } + + virtual void remove() = 0; + protected: + WeakReference() { + + } +}; + +/** + * Reference container is a vector of weak references that enables + * controllers to remove referenced objects as needed. + * + * There is no need to use weak ptrs here, as we do actually want + * the WeakReferences to be referenced counts. The "weak" aspect + * originates from and is defined by the corresponding object. + */ +class ReferenceContainer { + public: + ReferenceContainer() { + + } + + ~ReferenceContainer() { + + } + + void addReference(std::shared_ptr<WeakReference> ref) { + std::lock_guard<std::mutex> lock(mutex); + references.emplace_back(ref); + } + + size_t getReferenceCount() { Review comment: const (with mutable mutex)? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
