Difference between @Bean and @Autowired

difference between @bean and @component
bean vs autowired vs component
difference between @component and @autowired
bean annotation
autowired vs @inject
spring annotations
autowired(required = false)
difference between autowired and constructor injection

Why can't I use @Autowired in this case?

@SpringBootApplication
public class Application {

    @Autowired
    BookingService bookingService;

    public static void main(String[] args) {
        bookingService.book("Alice", "Bob", "Carol");
    }
}

but can use @Bean

@SpringBootApplication
public class Application {

    @Bean
    BookingService bookingService() {
        return new BookingService();
    }

    public static void main(String[] args) {
        ApplicationContext ctx = SpringApplication.run(Application.class, args);
        BookingService bookingService = ctx.getBean(BookingService.class);
        bookingService.book("Alice", "Bob", "Carol");
    }
}

Aren't the two ways to generate BookingService the same thing?

What is the difference between @Bean and Autowired in Spring , In short @Bean is producer and @Autowired is consumer, @Bean annotation let spring know instance of this class and it hold for it and� @Autowired – Defined in the package org.springframework.bean.factory and part of Spring framework. Here I am creating a simple interface Car which has two implementation classes Volkswagen and Toyota. We are going to inject these three types to understand the difference between these annotations. Lets look at the class below.

@Bean
BookingService bookingService() {
    return new BookingService();
}

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.

(i.e) The registered bean with @Bean annotation will be injected to the variable annotated with @Autowired.

Hope this clears your doubt!

Spring Bean Autowiring - @Autowired, Please note that if there isn't exactly one bean of the constructor argument type in the container, a fatal error is raised. Read More : Autowire by� The difference between @Inject vs. @Autowire vs. @Resource? @Autowired: spring propriety annotation (as opposed to @Inject and @Resource) that inject a resource by-type, i.e. by the class of by

great answer by @DaveyDaveDave In the example instead of

@Bean
  BookingService bookingService() {
    return new BookingService();
  }

You can use @Service annotation on BookingService class

Wiring in Spring: @Autowired, @Resource and @Inject, Learn the differences of using @Autowired on abstract classes vs. concrete classes Failure to define the bean in the application context will result in a� If you autowire a singleton bean, Spring looks for an existing instance inside the application context and provides it to you. If you autowire the bean in multiple places, Spring will still provide you with the same instance. When you autowire a prototype bean, Spring will initialize a new instance of the bean. If you autowire the bean in

Here's good article about @Autowired annotation: http://www.baeldung.com/spring-autowire

The @Autowired annotation can instantiate your injectables by defining @ComponentScan("namespace.with.your.components.for.inject") on config class

@Configuration
@ComponentScan("com.baeldung.autowire.sample")
public class AppConfig {}

All components must be marked by @Component annotation. It replaces the @Bean annotation.

Guide to Spring @Autowired, A guide to the most commonest usage of Springs @Autowired annotation and If more than one bean of the same type are available in the container, the� It use @Qualifier annotation to differentiate between the beans. @Resource is also Spring annotation, but it uses bean name to inject dependencies and differentiate between beans. Problem Statement :: Structure In order to show how @Autowired @Inject and @Resource annotations work we will create 3 services

@Bean is just for the metadata definition to create the bean(equivalent to tag). @Autowired is to inject the dependancy into a bean(equivalent to ref XML tag/attribute).

Spring Bean vs Spring Component – Home, Difference between @Bean and @Autowired . Scenario: We have a jar file which contains� This will indicate the bean name which needs to be Autowired in case of multiple beans with same type is present in the application context.(so that spring can autowire by name.) @Primary should be used in conjuction with @Bean / @Autowired which indicates which bean should be given higher preference, when there are multiple beans of same type

Difference between @Autowired and @Inject , A bean declared to be auto-wired using @Inject will work in both Google Guice and Spring framework, and potentially any other DI container which supports JSR -� @Qualifier. There may be a situation when you create more than one bean of the same type and want to wire only one of them with a property. In such cases, you can use the @Qualifier annotation along with @Autowired to remove the confusion by specifying which exact bean will be wired.

What is the difference between @Bean and Autowired in Spring?, difference between @bean and @component difference between bean and configuration in spring bean in spring default autowiring in spring difference� @Autowired and @Inject. 1.Match by Type-> bean with same Data type of the variable should be available in spring container. 2.Restricts by Qualifier-> If bean of variable’s data type not found or many implementation of the type available then it looks for any qualifier defined and if defined it uses Qualifier and wont go for 3rd option. 3.

Core Technologies - Project Metadata API Guide, Fine-tuning Annotation-based Autowiring with Qualifiers; 1.9.5. Beans, and the dependencies among them, are reflected in the enough to distinguish between each possible choice, this shortcut can save a lot of typing,� Spring framework provides the way to inject the bean dependencies using the autowire functionality. by default autowire functionality is disabled in spring framework. a developer explicitly define the autowiring configuration in spring configuration xml file. and this point is to remember that autowiring is only supported for object dependencies.the difference between bytype and byname

Comments
  • Bean annotation is for registering your bean in the spring context whereas Autowried annotation is for getting the bean from spring application content and wiring it as a dependency for another object
  • You should deliver the BookingService class too. Because if that is annotated with Component then your first class would also work like the second.
  • Somehow that answer appear only partly correct to me. Autowired can also call Objects annotated with @Components. Moreover Autowired can be used for Methods not only for objects.
  • @PowerFlower, absolutely right, my point here was to explain the difference in the context of the question. Certainly there is plenty more complexity in both annotations, but I was trying to give a simple, high-level explanation for this specific example.
  • but I can't use BookingService's fucntion if I inject BookingService with @Autowired
  • Now I know it is because in the main() I got error "change modifier of book() to static" ,I can use BookingService's object in other functions.But I don't why
  • @zhuochenshen I am not sure what is inside of you class and current problem. I answered only your "difference" question. You can post another question regarding to your next problem.
  • I.E,registered bean with @Bean will be inject to the variable annotated with @Autowired. This line turns out to be the essence of all what these two annotations are about.