- What is the use of @component in spring boot?
- What is the use of @service annotation in spring?
- What’s the difference between @component @repository & @service annotations in spring?
- Can we use @component instead of @repository?
- Is @component a singleton?
- What is @controller in spring?
- What is the difference between @component and @bean?
- What is the use of @repository?
- What is difference between @component and @service?
- What is spring bean life cycle?
- What is a bean in spring?
- What is @ComponentScan?
- What is @controller annotation in spring?
- Can we replace @controller with @component?
What is the use of @component in spring boot?
@Component is the most generic Spring annotation.
A Java class decorated with @Component is found during classpath scanning and registered in the context as a Spring bean.
@Service , @Repository , and @Controller are specializations of @Component , which are used for more specific cases..
What is the use of @service annotation in spring?
Spring @Service annotation is used with classes that provide some business functionalities. Spring context will autodetect these classes when annotation-based configuration and classpath scanning is used.
What’s the difference between @component @repository & @service annotations in spring?
Differences in NutShell: Both @Service and @Repository annotations are the specializations over the @Component annotation. @Repository is a stereotype used for persistence layer. It translates any persistence related exceptions into a Spring’s DataAccessException. @Service is used for the beans at the service layer.
Can we use @component instead of @repository?
The difference between them is, @component is used to annotate compound classes, @Repository is a marker for automatic exception translation in the persistence layer, for service layer we need to use @service. You can refer Spring Documentation to know more.
Is @component a singleton?
Yes, that is correct, @Component is a Spring bean and a Singleton. About singletons – spring beans are all in singleton scope by default.
What is @controller in spring?
Controller – A controller contains the business logic of an application. Here, the @Controller annotation is used to mark the class as the controller. … Front Controller – In Spring Web MVC, the DispatcherServlet class works as the front controller. It is responsible to manage the flow of the Spring MVC application.
What is the difference between @component and @bean?
Both approaches aim to register target type in Spring container. The difference is that @Bean is applicable to methods, whereas @Component is applicable to types. Therefore when you use @Bean annotation you control instance creation logic in method’s body (see example above). With @Component annotation you cannot.
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.
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 spring bean life cycle?
Advertisements. The life cycle of a Spring bean is easy to understand. When a bean is instantiated, it may be required to perform some initialization to get it into a usable state. Similarly, when the bean is no longer required and is removed from the container, some cleanup may be required.
What is a bean in spring?
In Spring, the objects that form the backbone of your application and that are managed by the Spring IoC container are called beans. A bean is an object that is instantiated, assembled, and otherwise managed by a Spring IoC container. Otherwise, a bean is simply one of many objects in your application.
What is @ComponentScan?
The @ComponentScan annotation is used with the @Configuration annotation to tell Spring the packages to scan for annotated components. … The @ComponentScan annotation uses the basePackages attribute to specify three packages (and subpackages) that will be scanned by Spring.
What is @controller annotation in spring?
Annotation Type Controller Indicates that an annotated class is a “Controller” (e.g. a web controller). This annotation serves as a specialization of @Component , allowing for implementation classes to be autodetected through classpath scanning.
Can we replace @controller with @component?
2 Answers. @Controller is a @Component (just like @Service , @Repository , @Endpoint etc.). The @Component is used as a meta-annotation here so that it can be picked-up using component-scanning. Next to that the @Controller is a special component which will have some added functionality (Spring MVC takes care of that).