Spring_通过注解实现MVC案例

配置好aop beans context 4.2的xsl

@Scope：控制是否以单例的形式产生对象

@Component（修饰控制层）下分为@Controller、@Service、@Repository，效果一样

@Controller：修饰控制层

@Service：修饰业务层，将业务层对象的创建交给spring容器

@Repository：修饰DAO层，将DAO层对象的创建交给spring容器

用了这几个，后面的括号都不用写了。

DAO层：

package cn.java.annotationioc;

import org.springframework.stereotype.Component;
import org.springframework.stereotype.Repository;

@Repository
public class FrontDaoImpl {
    
    public void addUser() {
        System.out.println("添加成功");
    }
}

Service层：

package cn.java.annotationioc;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class FrontServiceImpl {
    
    @Autowired
    private FrontDaoImpl fdi;
    public void userAdd() {
        fdi.addUser();
    }
}

Servlet层：

package cn.java.annotationioc;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component("frontServlet")
public class FrontServlet {
    
    @Autowired
    private FrontServiceImpl fsi;

    public void doGet() {
        fsi.userAdd();
    }
}

主层：

package cn.java.annotationioc;


import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Window {

    public static void main(String[] args) {

        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        FrontServlet fs = (FrontServlet) context.getBean("frontServlet");
        fs.doGet();
    }

}

主xml：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans 
        http://www.springframework.org/schema/beans/spring-beans-4.2.xsd
        http://www.springframework.org/schema/aop 
        http://www.springframework.org/schema/aop/spring-aop-4.2.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context-4.2.xsd">

    <context:component-scan base-package="cn.java."></context:component-scan>

</beans>