Spring Framework Bean Configuration (3): annotation-based configuration, autowired Automatic assembly bean, generic dependency Injection

1. Annotation-based configuration:

@Component: Basic annotations that identify a component that is managed by Spring

@Respository: Identifying durable layer components

@Service: Identify service layer (business layer) components

@Controller: Identify presentation layer components

Build Interface: Userrepository

 Package com.atguigu.spring.beans.annotation.test;  Public Interface userrepository {    void  Save ();}

Build class: Userrepositoryimpl inherits from Interface: Userrepository

 Package com.atguigu.spring.beans.annotation.test; Import org.springframework.stereotype.Repository; @Repository (// Identity Persistence layer component  Public Classimplements  userrepository {    publicvoid  Save () {        System.out.println ("panpan123");}    }

Build class: UserService

 Package com.atguigu.spring.beans.annotation.test; Import org.springframework.stereotype.Service; @Service   // Identify service layer (business layer) components  Public class UserService {    publicvoid  Add () {        System.out.println (" panpan456 ");}    }

Build class: Usercontroller

 Package com.atguigu.spring.beans.annotation.test; Import Org.springframework.stereotype.Controller; @Controller   // Identify presentation layer components  Public class Usercontroller {    publicvoid  Test () {        System.out.println (" panpan789 ");}    }

The above classes are built under the package com.atguigu.spring.beans.annotation.test;

Spring XML configuration file: Beansannotation.xml, with the above four annotations under a Com.atguigu.spring.beans.annotation.test package or sub-package, can be identified by the IOC container

<context:component-scan  base-package = "Com.atguigu.spring.beans.annotation.test" >    </ Context:component-scan>

Spring Framework Bean Configuration (3): annotation-based configuration, autowired Automatic assembly bean, generic dependency Injection