依赖注入7（配置文件注解实现三层(自动注入)）

1.javabean

package com.bean;

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

@Component
public class User {

 private String username;
 private String password;
 
 public String getUsername() {
  return username;
 }

 public void setUsername(String username) {
  this.username = username;
 }

 public String getPassword() {
  return password;
 }

 public void setPassword(String password) {
  this.password = password;
 }
 @Override
 public String toString() {
  return "User [username=" + username + ", password=" + password + "]";
 }
 
}

2.dao

package com.dao;

public interface UserDao {

 public void print(String username,String password);
}

3.daoImpl

package com.dao;

import javax.management.loading.PrivateClassLoader;

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

import com.bean.User;

@Repository
public class UserDaoImpl implements UserDao{
 @Autowired
 private User user;
 @Override
 public void print(String username,String password) {
  System.out.println("UserDaoImpl："+username+"\t"+password);
  user.setUsername(username);
  user.setPassword(password);
  System.out.println(user);
 }
}

4.service

package com.service;

public interface UserService {

 public void print(String username,String password);
}

5.serviceImpl

package com.service;

import javax.annotation.Resource;
import javax.enterprise.inject.New;

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

import com.dao.UserDao;
import com.dao.UserDaoImpl;

@Service("userservice")
public class UserServiceImpl implements UserService{

 /**
  *  先将注解得到的对象存入到IOC容器中
  *  @Autowired:默认是按照对象的数据类型进行自动装配
        @Autowired
        private UserDao userDao;
  Spring框架会从IOC容器中自动将类型为UserDao的对象注入进来。
  @Resource:默认是按照名称或者ID进行自动装配，只有找不到匹配的名称或者ID时才按照类型进项装配
        @Resource(name="userDao")
        private UserDao userDao;
  Spring框架在运行时会从IOC容器中根据名称或者ID为“userDao”的对象注入进来。
  * */
 @Autowired
 private UserDao userdao;
 @Override
 public void print(String username,String password) {
  System.out.println("UserServiceImpl："+username+"\t"+password);
  userdao.print(username,password);
 }
}

6.配置文件

<?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:context="http://www.springframework.org/schema/context"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
  http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
  http://www.springframework.org/schema/context
  http://www.springframework.org/schema/context/spring-context-4.3.xsd">
  <context:component-scan base-package="com.bean"></context:component-scan>
  <context:component-scan base-package="com.dao"></context:component-scan>
  <context:component-scan base-package="com.service"></context:component-scan>
</beans>

7.测试类

package com.Test;

import javax.faces.application.Application;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.stereotype.Controller;

import com.dao.UserDao;
import com.service.UserService;
import com.service.UserServiceImpl;

//@Controller
public class test {
 @Test
 public void Controller(){
  ApplicationContext context=new ClassPathXmlApplicationContext("config.xml");
  UserService userService=(UserService) context.getBean("userservice");
  userService.print("wangyujie","123");
 }
}