producer-consumer

问题 I have a producer in java and consumer in nodeJS. I want to know in java what is the consumer lag, so i know if i can produce more data to the topic. What is the API in java to get the consumer lag? 回答1: Why do you need to know the consumer lag ? The aim of a broker is to produce messages asynchronously. If you need to have a synchronous processing, use a basic rest processing. 回答2: The actual class you can call from Java is the kafka.admin.ConsumerGroupCommand . It's Scala code, but it's

问题 I'm using a thing called react-firebase-js to handle firebase auth, but my understanding of react and of the provider-consumer idea is limited. I started with a built a very big JSX thing all at the top level, and that works without warnings. But when I try to break it into components, I got the warning shown in the title and a few others. This works without warning... // in App.js component render() { return ( <header className="App-header"> <img src={logo} className="App-logo" alt="logo" />

问题 I wish to know if my understanding of the producer consumer design is correct by using the ExecutorService & ArrayBlockingQueue. I understand there are different ways to implement this design but I guess, at the end, it depends on the problem itself. The problem I had to confront is this: I have a ONE producer who reads from a big file (6GB); it reads line by line and converts every line to an object. It places the object in an ArrayBlockingQueue. The consumers (few) take the object from the

问题 I am trying to solve a multiple producer single consumer problem with the producers generating integers and the consumer making a sorted list out of all these integers(using AVL tree). How should I be locking my tree data structure? Or is it unnecessary? The queue has proper locking for push and pop operations. void consumer(NaiveQueue<nodeQ> &obj) { while(1) { nodeQ *temp; temp=NULL; temp=obj.pop(); if(temp) { cout << "\nRemoved : " << temp->data; root=insert(root,temp->data); //****lock

问题 I am new to Activemq and Java ,I read tutorials,somewhat I understand.can anyone help me to solve the following task. Imagine we have a 10 messages in Queue/Topic of Activemq. we are getting messages from Database,we already did it. I want to write 2 Java Applications (using JMS for receiving messages from activemq ) that will act as a consumer in Activemq. What i want to achieve out of this is that whenever Activemq get messages from Database, activemq should check if any consumer is free or

问题 NOTE : I have this goal and I have many doubts, but I take the opportunity to do them all because I do not know if it would be advisable to open different posts with the same code / problem. I have a producer ( RunnableProducer ) that has multiple consumers that are called RunnableWorker . The RunnableWorker may have several consumers of its same class.. Finally, its information is consumed by simple consumers RunnableConsumer . The information can change in size, increasing or decreasing

问题 I have added a Mutex class to adhere to RAII. I am not sure if the way I am using it is correct. After the queue is locked by a producer, the program unexpectedly finishes. MutexClass.h #ifndef MUTEXCLASS #define MUTEXCLASS #include <pthread.h> class MutexClass { private: pthread_mutex_t & _mutexVariable; public: MutexClass (pthread_mutex_t &); ~MutexClass (); }; #endif // MUTEXCLASS MutexClass.cpp #include "mutexClass.h" #include <stdexcept> MutexClass::MutexClass (pthread_mutex_t & arg) :

问题 I saw a snippet of code in this question which I could not understand (most probably due to the fact am a beginner in this area). The question talks about "an obvious race condition where sometimes the producer will finish, signal it, and the ConsumerWorkers will stop BEFORE consuming everything in the queue." In my understanding, "isRunning" will be set on the consumers only after the producer decides not to add anymore items in the queue. So, if a consumer thread sees isRunning as FALSE AND

问题 I'm reading 'Java Concurrency in Practice', one example sort of makes me confused, it's about producer-consumer logging service: public class LogWriter { private final BlockingQueue<String> queue; private final LoggerThread logger; private boolean shutdownRequested = false; public LogWriter(Writer writer) { this.queue = new LinkedBlockingQueue<String>(CAPACITY); this.logger = new LoggerThread(writer); } public void start() { logger.start(); } public void shutdownlog() { shutdownRequested =

问题 Hoping someone can give some advice regarding the Producer/Consumer Pattern – in particular on how best to achieve a Queue/BlockingCollection which is COMMON to all producers/consumer class instances? Lets Simplify the scenario; Consider I have; A single Producer class A single single Consumer class. A Service Class which contains instances of both the Producer and Consumer Class. The Service Class simply tells the Producer/Consumer to Start and Stop Work. The producer will populate a