Question: What Is The Difference Between @Component And @Bean In Spring?

What does @component do in spring?

Spring Component annotation is used to denote a class as Component.

It means that Spring framework will autodetect these classes for dependency injection when annotation-based configuration and classpath scanning is used..

How do I use Autowired in spring?

In Spring, you can use @Autowired annotation to auto wire bean on the setter method, constructor or a field. Moreover, it can autowired property in a particular bean. The @Autowired annotation is auto wire the bean by matching data type. See following full example to demonstrate the use of @Autowired.

What is IoC in spring with example?

An IoC container is a common characteristic of frameworks that implement IoC. In the Spring framework, the IoC container is represented by the interface ApplicationContext. The Spring container is responsible for instantiating, configuring and assembling objects known as beans, as well as managing their lifecycle.

What does @repository mean 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 does Autowired mean in spring?

Autowiring feature of spring framework enables you to inject the object dependency implicitly. It internally uses setter or constructor injection. Autowiring can’t be used to inject primitive and string values. It works with reference only.

What is @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.

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

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.

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 @qualifier annotation in spring?

The @Qualifier annotation is used to resolve the autowiring conflict, when there are multiple beans of same type. The @Qualifier annotation can be used on any class annotated with @Component or on method annotated with @Bean . This annotation can also be applied on constructor arguments or method parameters.

What is the use of @repository in spring?

Spring @Repository annotation is used to indicate that the class provides the mechanism for storage, retrieval, search, update and delete operation on objects.

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.

What is the use of @configuration in spring?

Spring @Configuration annotation helps in Spring annotation based configuration. @Configuration annotation 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 use of @autowired in spring?

Advertisements. The @Autowired annotation provides more fine-grained control over where and how autowiring should be accomplished. The @Autowired annotation can be used to autowire bean on the setter method just like @Required annotation, constructor, a property or methods with arbitrary names and/or multiple arguments …

What is the use of @bean in spring?

Spring @Bean Annotation is applied on a method to specify that it returns a bean to be managed by Spring context. Spring Bean annotation is usually declared in Configuration classes methods. In this case, bean methods may reference other @Bean methods in the same class by calling them directly.

What is 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 is difference between @component and @bean?

@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 @controller in spring?

The @RestController annotation was introduced in Spring 4.0 to simplify the creation of RESTful web services. It’s a convenience annotation that combines @Controller and @ResponseBody – which eliminates the need to annotate every request handling method of the controller class with the @ResponseBody annotation.

Why Autowiring is used in spring?

Spring can autowire a relationship between collaborating beans without using constructor-arg and property tags which helps with the amount of XML configuration. Autowiring of the Spring framework enables you to inject the object dependency implicitly. …