ActiveMQ Interview Questions

ActiveMQ Interview Questions For Freshers & Experienced

Sharad Jaiswal

25th Dec, 2019

765 Followers

What is ActiveMQ?

ActiveMQ, written in Java is an open-source communication arbitrator, along with JMS. It offers to foster communication from various servers or clients. The supporter clients comprise of Java JMS 1.1 and additional “cross-language” consumers. This type of communication is executed with attributes like computer clustering, the capability to utilize any database similar to JMS persistence giver besides cache, journal persistency, and virtual memory.

ActiveMQ is best known for its support of carrier protocols including STOMP, MQTT, REST, WebSocket’s, Open Wire, AMPQ, and pliability in the configuration. It employs many modes that offer high availability, comprising both database and a file-system locking mechanism that shares persistence store through true replication utilizing Apache Zookeeper, or shared filesystem.

Key Features of Activemq

Below are few major features of Activemq

Real Time Broadcasting

Enterprise Integration Patterns

JMX Support

Command line interface

AMQ Message Store

Command Agent

Message Transformation

Mirrored Queues

Producer Flow Control

Q1. What is ActiveMQ server?

ActiveMQ is an open-source message broker that provides features such as fostering communication from more than one client or software. This message broker is written in Java with a full JMS (Java Message Service) client. Other cross-language clients apart from the JMS are also supported by the ActiveMQ server. It provides advanced features like message load balancing and high-availability of data among others.

ActiveMQ is commonly deployed as a standalone process. In this way, ActiveMQ is isolated from any particular application and provides maximum flexibility for resource allocation and management. This cross-platform messaging service was founded by LogicBlaze in 2004.

Q2. For what ActiveMQ is used?

ActiveMQ is an open-source message broker which is used for reliably doing communication between two distributed processes. It is designed for the purpose of sending messages between two applications, or two components inside one application. Message Oriented Middleware (MOM) implementations.

Q3. How to start ActiveMQ server?

Below are steps to start ActiveMQ server

Step 1: Cd to the bin folder of your ActiveMQ installation.
Step 2: Run activemq start the command to start the server.

Q4. What is difference between JMS and ActiveMQ?

ActiveMQ is a message brokering service that implements JMS API and supports other cross-language clients and protocols. With ActiveMQ, you can implement queues or topis and write subscribers or listeners to respond to the queue events. JMS is a Java-based messaging protocol specification that is fundamental to other technologies.

The difference between them is that ActiveMQ is an implementation of the JMS (Java Messaging Service) and JMS is just a protocol specification.

Q5. What is ActiveMQ Artemis?

ActiveMQ Artemis is an open-source project for an asynchronous messaging system. It is high performance, embeddable, clustered and supports multiple protocols.

Q6. What is JMS?

JMS is an application programming interface(API) that provides Java language functions for handling messages. It was developed by IBM in partnership with Sun Microsystems. It is used for sending messages between two or more clients.

Q7. Explain the architecture of Activemq?

The architecture of apache ActiveMQ contains three main parts. They are broker, destinations, and client applications.

The client applications in the ActiveMQ uses the org.apache.ActiveMQ package to define the core JMS client. Non-JMS clients can also connect to the ActiveMQ broker using the AMQP, MQTT, and STOMP protocols.

ActiveMQ uses a broker as an intermediatory between the clients and the destinations. The APIs for the message broker is defined in the package org.apache.activemq.broker.

The client and the message broker use the Transport abstraction to send and receive the objects.

Q8. What is difference between ActiveMQ and Mule?

As we have previously mentioned, ActiveMQ is a message broker that implements the JMS API. It is used to implement listeners and subscribers to respond to queue events. It also has features such as high-availability of data and message load balancing feature. Whereas, Mule is an open-source Enterprise service bus.

This Enterprise Service Bus has capabilities beyond the JMS like message transformation, routing, logging, security, etc.

Q9. What protocols are supported by ActiveMQ?

MQP, MQTT, OpenWire, and STOMP are few protocols that are supported by ActiveMQ.

Q10. What is default port of ActiveMQ?

8161 is the default port of ActiveMQ.

About Author :

Sharad Jaiswal

Sharad Jaiswal is Sr. Web Developer from Noida area. He have rich experience in PHP, Angular Js, React, javascript and Node .If you any query or project on these programming you can drop your enquiry in comment section.