In order to crack Spring Boot interviews, you need to have a clear and solid grasp on the concepts of Spring Framework and their different sub-projects such as Spring MVC, REST, Spring Data JPA, Testing, Spring Cloud, etc.
What increases your chances to be selected?
If you have worked on the Spring Boot projects, then it makes you familiar with key concepts like auto-configuration, actuator and started dependencies. Those are a must, and if you haven’t built a project yet, write a Spring Boot program and build a Spring Boot project from scratch. Once you have gained that experience, you can go through each topic and try to answer questions on your own.
The best approach to crack the spring boot interview is to ask questions to yourself, and if you don’t know, then look at the answer and research it to learn better. This approach takes time.
If you lack time, then only one thing can be done. Go through the questions as soon as possible and revise the essential concepts, and have ideas about each of them. We will be discussing the major topics in this blog.
Some important concepts you need to know before acing the interviews:
- Core Spring
Spring boot interview questions are one of the first things Java Programmers must prepare for before applying for any Java or Spring Boot interview. Spring Framework is a very popular structure of Java applications, which helps in simplifying Java development. The Spring framework had revolutionized Java development when it introduced the concepts of Dependency Injection and Inversion of Control, which made writing testable and maintainable Java applications. Spring Framework also provides Java programmers with useful APIs. The spring framework is divided into several modules like Spring MVC, Spring Integration, Spring Batch, Spring LDAP, Spring Security, Spring Boot, Spring Cloud, and several other modules which focus on a particular area.
Let’s have a look at some examples. The modules like the Spring Boot simplifies the use of the spring framework by reducing the amount of configuration you need to put in for Spring itself. Spring Cloud is evolving to become the best framework for cloud-based Java frameworks and Microservices, which is a major need for the future. Moreover, Spring Security has established itself as the go-to framework for security Java web applications.
- What is the Spring Framework? Why should Java programmers use the Spring Framework?
Spring is a framework that helps Java Programmers in development. In fact, spring is now the most popular Java Framework, and most of the Java server-side development is using spring.
- What is the Spring Boot module?
Spring greatly simplifies several programming tasks, reducing and sometimes eliminating much of the boilerplate code you might normally be required to write without it. Spring Boot is an exciting new project that takes a self-opinionated read of developing with spring to simplify spring itself.
Spring Boot heavily employs automatic configuration techniques which can eliminate most or rather all Spring configuration. It also provides several starter projects to help reduce the size of your Spring project build files, whether you are using Maven or Gradle.
- What is Microservice?
Micro Service is an architecture that enables the developers to develop and deploy services independently. Each of the services running has its own method and this achieves the lightweight model to help business applications.
- What are the two advantages provided by micro services to its developers?
Microservices offers the given advantages to its developers:
- Easy deployment
- Simple scalability
Spring Boot provides a decent platform for Java developers. It enables the developers to develop a stand-alone and production-grade spring application that you can just run.
- What are the two basic goals of Spring Boot?
Spring Boot is designed with the following basic goals:
- To avoid complex XML configuration in Spring.
- To develop a production ready Spring application in a better means.
- What is Inversion of Control (IoC)?
Inversion of Control (IoC) is a design principle of the Spring framework within which custom-written portions of a computer program receive the flow of control from a generic framework. Inversion of control serves the following purposes:
a. It is used to increase or add upon the modularity of program and make it extensible.
b. To decouple execution of a task and from implementation.
c. To focus a module on a task it’s designed for.
d. To free modules from assumptions about how other systems do and rather than that rely on contracts.
e. To prevent the side effects when replacing a module.
There are several basic techniques to apply Inversion of Control (IoC) in our programs:
– Using a factory pattern
– Using a service locator pattern
– Using a dependency injection (constructor, parameter, setter, and interface injection)
– Using a contextualized lookup
– Using template method design pattern.
- What is the difference between Inversion of Control (IoC) and dependency injection (DI)?
Inversion of Control is more generic. Dependency Injection (DI) is an implementation of Inversion of Control.
- What is the Advantage Of Spring framework?
The Spring Boot framework addresses most of the infrastructure functionalities of the enterprise applications.
- It enables developers to develop enterprise applications using POJOs (Plain Old Java Object). The benefit of using POJO is that we don’t need to have an enterprise container as we have the option of using a robust servlet container.
- Spring provides an abstraction layer on existing technologies like servlets, jsps, jdbc, jndi, rmi, jms, and Java mail etc., to simplify the development process.
- Spring already comes with ORM framework, logging framework, J2EE and JDK Timers etc. It’s web framework has a well-designed MVC framework which provides a great alternative to legacy frameworks.
- It provides a consistent transaction management interface.
- Spring supports both xml and annotation configurations.
- It gives built in middleware services like Connection Pooling, Transaction Management etc.
- What are the benefits of dependency injection?
A single Spring Boot starter dependency can replace several common dependencies in a Maven or Gradle build. For example, adding only a Spring Boot’s web starter as a dependency in a projects pulls in Spring’s web and Spring MVC modules as well as the Jackson 2 databind module.
- What are the three primary wiring mechanisms in Spring?
Spring is incredibly flexible and thus offers these three wiring mechanisms:
- Explicit configuration in XML.
- Explicit configuration in Java.
- Implicit bean discovery and automatic wiring.
- What is the Spring Boot actuator?
The Spring Boot Actuator brings a handful of useful features to a Spring Boot project such as:
- Management Endpoints
- Sensible Error handling and also has a default mapping for an /error endpoint.
- An /info endpoint which can communicate information about an application.
- An audit events framework when Spring Security is in play.
- How do you eliminate boilerplate configuration in a Spring Project?
Spring Boot employs two main tricks to eliminate boilerplate configuration in a Spring project: Spring Boot starters and automatic configuration.
- How to use Groovy with Spring Boot CLI?
The syntax of Groovy is much simpler than Java. If you are willing to write your application code in Groovy and run it through Spring Boot’s CLI, then Spring Boot can benefit from Groovy’s simplicity to further simplify Spring development.
Spring Boot is an exciting new addition to the Spring framework.
The Spring framework aims to make Java development simpler, and Spring Boot aims to make Spring itself simpler.
Spring Boot’s CLI further simplifies Spring projects with Groovy. By simply referencing a Spring component in a Groovy code, you can trigger the CLI to automatically add the necessary starter dependency. Moreover, many Spring types don’t require explicit import statements in Groovy code run via the Spring Boot CLI.
Refer to some books that just focus on the Spring Framework, work on the interview questions and do some great projects to impress your interviewer and gain more knowledge about Spring and Spring Boot.
Hope this article helps you a lot for understanding this topic. If you’re interested in free online courses with certificates, So enroll today on Great Learning Programme.