Under what circumstances do you need to manually write the @bean to the container to complete the implementation class

Springboot In the project
Whenever a method is encountered, it needs to return Its corresponding implementation class when
So you need to implement this class , You use @Autowired Introduce
But after the introduction of this class not always Exist Bean In container

So write this blog post to record how to judge whether it is necessary to @Bean The introduction of

for example （ Situations that need to be manually added to the container ）

This is a code about rewriting the configuration class ,
You can see endpoints.authenticationManager() This method
Need one AuthenticationManager Implementation class

How to determine whether manual operation is required @Bean Add a container ？
adopt ctrl+ left-click Enter this class

I found that this class is No, Inject into the container , So we need to Manual Add this class to the container .

contrast （ Situations that do not require manual implementation ））

RedisTokenStore（） There needs to be a RedisConnectionFactory class
ctrl+ left-click Enter this class

You can find that this class has been injected into the container , Manual injection is not required
You can go directly through **@Autowired** It can be used after being introduced .