Quick Answer: What Is The Use Of @Bean In Spring?

What is the purpose of @autowired in spring?

Starting with Spring 2.5, the framework introduced annotations-driven Dependency Injection.

The main annotation of this feature is @Autowired.

It allows Spring to resolve and inject collaborating beans into our bean..

What is use of @configuration in spring?

@Configuration annotation is used for Spring annotation based configuration. The @Configuration is a marker annotation which indicates that a class declares one or more @Bean methods and may be processed by the Spring container to generate bean definitions and service requests for those beans at runtime.

What is the difference between @configuration and @component in Spring?

@Component Indicates that an annotated class is a “component”. Such classes are considered as candidates for auto-detection when using annotation-based configuration and classpath scanning. A @Configuration is also a @Component, but a @Component cannot act like a @Configuration.

How many types of Autowiring are there in spring?

This is called spring bean autowiring. The autowiring functionality has four modes. These are ‘ no ‘, ‘ byName ‘, ‘ byType ‘ and ‘ constructor ‘. Another autowire mode autodetect has been deprecated.

What is spring bean life cycle?

A “Spring bean” is just a Spring managed instantiation of a Java class. The Spring IoC container is responsible for instantiating, initializing, and wiring beans. The container also manages the life cycle of beans. Spring provides several ways through which you can tap into the bean lifecycle.

What is the use of @service annotation in spring?

@Controller annotation is an annotation used in Spring MVC framework (the component of Spring Framework used to implement Web Application). The @Controller annotation indicates that a particular class serves the role of a controller.

What is @repository annotation in spring?

@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 the difference between @component and @bean in spring?

@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 @bean used for?

@Bean is a method-level annotation and a direct analog of the XML element. The annotation supports most of the attributes offered by , such as: init-method , destroy-method , autowiring , lazy-init , dependency-check , depends-on and scope .

What is the difference between @bean and Autowired?

Annotating @Bean only registers the service as a bean(kind of an Object) in spring application context. In simple words, it is just registration and nothing else. @Autowired BookingService bookingService; Annotating a variable with @Autowired injects a BookingService bean(i.e Object) from Spring Application Context.

What does @component mean in spring?

@Component annotation means that only a single instance of the annotated class gets created. Also in most cases this instance is automatically created on application startup, perhaps when some other common Spring annotations are used.

What is use of @bean annotation in spring?

Annotating a class with the @Configuration indicates that the class can be used by the Spring IoC container as a source of bean definitions. The @Bean annotation tells Spring that a method annotated with @Bean will return an object that should be registered as a bean in the Spring application context.