What Is The Difference Between @Component @Controller @Repository & @Service Annotations?

What is the difference between @component @repository @service and @controller?

@Component is a generic annotation.

Difference of @Service, @Repository, @Controller with @Component is they are special cases of @Component and used for particular purposes.

The difference is just classification only.

For all these annotations (stereotypes), technically the core purpose is same..

What is the difference between @component and @ComponentScan?

Using the annotation @ComponentScan , you can tell Spring where do your Spring-managed components lie. … On the other hand, @Component is a generic annotation for any Spring-Managed component. For example – If you create a class called Testing inside the package com. example.

Is @component a singleton?

2 Answers. Yes, that is correct, @Component is a Spring bean and a Singleton. About singletons – spring beans are all in singleton scope by default. The only thing you have to have in mind is that you should not store state in field variables (they should only hold dependencies).

What is difference between @component and @service?

@Component is a generic stereotype for any Spring-managed component or bean. @Repository is a stereotype for the persistence layer. @Service is a stereotype for the service layer. @Controller is a stereotype for the presentation layer (spring-MVC).

What is difference between @inject and @autowired?

The @Autowired annotation is used for auto-wiring in Spring framework. … The @Inject annotation also serves the same purpose, but the main difference between them is that @Inject is a standard annotation for dependency injection and @Autowired is spring specific.

What is difference between @bean and @component?

@Component is a class level annotation whereas @Bean is a method level annotation and name of the method serves as the bean name. @Component need not to be used with the @Configuration annotation where as @Bean annotation has to be used within the class which is annotated with @Configuration.

What is the @controller annotation used for?

The basic purpose of the @Controller annotation is to act as a stereotype for the annotated class, indicating its role. The dispatcher will scan such annotated classes for mapped methods, detecting @RequestMapping annotations (see the next section).

Can we use @component instead of service?

@Service and @Repository are special cases of @Component. They are technically the same but we use them for the different purposes.

What is the use of @repository?

@Repository is a Spring annotation that indicates that the decorated class is a repository. A repository is a mechanism for encapsulating storage, retrieval, and search behavior which emulates a collection of objects.