导入jar包:
进入项目结构:
选择文件夹:
![](https://img2022.cnblogs.com/blog/2651506/202205/2651506-20220524135810097-1572655191.png)
选择jar包确定:
这里创建一些测试类:
package dao.impl;
import dao.IUserDao;
public class UserDaoImpl implements IUserDao {
@Override
public void getUser() {
// 查询数据库
System.out.println("查询MySQL");
}
}
package dao;
public interface IUserDao {
void getUser();
}
package service.impl;
import dao.IUserDao;
import dao.impl.UserDaoImpl;
import service.IUserService;
public class UserServiceImpl implements IUserService {
IUserDao dao;
public IUserDao getDao() {
return dao;
}
public void setDao(IUserDao dao) {
this.dao = dao;
}
@Override
public void getUser() {
dao.getUser();
}
}
package service;
public interface IUserService {
void getUser();
}
package test;
import dao.IUserDao;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import service.IUserService;
import service.impl.UserServiceImpl;
public class MyTest {
public static void main(String[] args) {
// 加载IOC
ApplicationContext ioc = new ClassPathXmlApplicationContext("spring.xml");
// 获取类实例
IUserService service = ioc.getBean(IUserService.class);
service.getUser();
}
}
配置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"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean class="dao.impl.UserDaoImpl" id="userDao"/>
<bean class="service.impl.UserServiceImpl" id="userService">
<property name="dao" ref="userDao"/><!-- 将ref中的类注入到name对应的实例中 -->
</bean>
</beans>
然后还需要导入一个包:
这个包实现lcommons-logging的功能,如果不导入则会报错;
运行结果:
如果此时需要更换查询的数据库,只需要在xml中更改一个名称:
![](https://img2022.cnblogs.com/blog/2651506/202205/2651506-20220524142125791-1330563708.png)
运行结果: