Spring Boot Interview Questions

Spring Boot is a one-stop Framework to develop Spring applications very easily. I have covered a lot of spring interview questions earlier, this is specifically for spring boot interview questions and answers. These spring boot interview questions are good for experienced programmers as well as new to spring boot framework.

What is Spring Boot?

In simple words, Spring Boot Framework is Auto-Dependency Resolution, Auto-Configuration, Management EndPoints, Embedded HTTP Servers(Jetty/Tomcat etc.) and Spring Boot CLI In other words, Spring Boot Framework is Spring Boot Starter, Spring Boot Auto-Configurator, Spring Boot Actuator, Embedded HTTP Servers, and Groovy. In other words, Spring Boot Framework is Spring Boot CLI. NOTE:- If you are confused about the last two definitions, please read the rest of the post to make it clear.

Why we need Spring Boot?

1. Spring Framework aims to simplify Java Applications Development.
2. Spring Boot Framework aims to simplify Spring Development.

Spring Boot Components

Spring Boot Framework has the following components:

1. Spring Boot Starter
2. Spring Boot AutoConfigurator
3. Spring Boot Actuator
4. Spring Boot CLI
5. Spring Boot Initilizr

What is Spring Boot Starter?

Spring Boot Starters are just JAR Files. They are used by Spring Boot Framework to provide “Auto-Dependency Resolution”.

What is Spring Boot AutoConfigurator?

Spring Boot AutoConfigurator is used by Spring Boot Framework to provide “Auto-Configuration”.

What is Spring Boot Actuator?

Spring Boot Actuator is used by Spring Boot Framework to provide “Management EndPoints” to see Application Internals, Metrics etc.

What is Spring Boot CLI?

In simple words, Spring Boot CLI is Auto Dependency Resolution, Auto-Configuration, Management EndPoints, Embedded HTTP Servers(Jetty, Tomcat etc.) and (Groovy, Auto-Imports) In other words, Spring Boot CLI is Spring Boot Starter, Spring Boot Auto-Configurator, Spring Boot Actuator, Embedded HTTP Servers, and Groovy. With Spring Boot CLI:

• No Semicolons
• No Public and private access modifiers
• No Imports(Most)
• No “return” statement
• No setters and getters
• No Application class with main() method(It takes care by SpringApplication class).
• No Gradle/Maven builds.
• No separate HTTP Servers.

What is Spring Boot Initilizr?

Spring Boot Initilizr is a Spring Boot tool to bootstrap Spring Boot or Spring Applications very easily. Spring Boot Initilizr comes in the following forms:

1. Spring Boot Initilizr With Web Interface
2. Spring Boot Initilizr With IDEs/IDE Plugins
3. Spring Boot Initilizr With Spring Boot CLI
4. Spring Boot Initilizr With ThirdParty Tools

Why we need Spring Boot Initilizr?

Spring Boot Initilizr simplifies Spring Applications Development by providing initial project structure and build scripts.

• It reduces Development time
• It increases Productivity

Spring Boot With Maven/Gradle?

Spring Boot Framework uses one of the greatest features of Maven/Gradle build tools: “Transitively Dependency Resolution Management”.

What is “Transitively Dependency Resolution Management”?

“Transitively Dependency Resolution Management” means: If we define an “A” dependency in build scripts, “A” is dependent on “B” and “B” is dependent on “C”, That means “A” is also dependent on “C”. Then Build Tools will download and add all Three Jar files “A”, “B” and “C” to our application classpath. That’s all about Spring Boot interview questions and answers. If you want to learn these concepts in depth, please go through my previous posts one by one. You should also go through official documentation.