Apache Activemq Interview Questions and Answers (2021)
- Q: What Is ActiveMQ?
- Q: What is topic in ActiveMQ?
- Q: What is difference between ActiveMQ and AMQP?
- Q: Which open wire protocols ActiveMQ supports?
- Q: What are the advantages of combination of topics and queues over conventional topics?
Q: What Is ActiveMQ? Apache ActiveMQ is a Java-written open source message broker with Java Message Service (JMS) client.
Q: What is topic in ActiveMQ?
Virtual topics are combination of both topics and queues. The producers will write messages to the topic
whereas the listeners will consume messages from their own queue. ActiveMQ copies and duplicates every message to the actual consumer queues from the topic
Q: What is difference between ActiveMQ and AMQP? Advanced Message Queue Protocol (AMQP) is a standard for the interoperability of messaging clients and brokers. AMQP is a client-to-message broker communication wire-level protocol specification.AMQP is just a messaging
protocol and ActiveMQ is Messaging System.
Q: Which open wire protocols ActiveMQ supports? Ans:It supports below open wire protocols:
Q: What are the advantages of combination of topics and queues over conventional topics?
- Even if a consumer is offline, there will be no lost messages. ActiveMQ copies all messages to the queues that have been registered.
- If a consumer is unable to handle a message, a dead letter queue will be put on. The consumer can be resolved and the message can be transferred to his own dedicated queue without impacting the other consumer.
- To implement a load balancing mechanism we can register multiple instances of a consumer on a queue.