package com.inmind;

import com.inmind.mapper.UserMapper;
import com.inmind.pojo.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

@SpringBootTest //该注解的作用，启动spring环境，所以也就有了IOC容器
class SpringbootMybatisQuickstartApplicationTests {

    @Autowired//直接从IOC容器中获取UserMapper类型的对象
    private UserMapper userMapper;//接口开发，多态

    @Test
    void contextLoads() {
        //使用mybatis框架查询所有用户的数据
        List<User> list = userMapper.list();
        list.stream().forEach(user -> {
            System.out.println(user.getId());
            System.out.println(user);
        });
    }

    @Test
    void testJDBC() throws ClassNotFoundException, SQLException {
        //1. 注册驱动
        Class.forName("com.mysql.cj.jdbc.Driver");

        //2. 获取连接对象
        String url = "jdbc:mysql://localhost:3306/mybatis";
        String username = "root";
        String password = "1234";
        Connection connection = DriverManager.getConnection(url, username, password);

        //3. 获取执行SQL的对象Statement,执行SQL,返回结果
        String sql = "select * from user";
        Statement statement = connection.createStatement();
        ResultSet resultSet = statement.executeQuery(sql);

        //4. 封装结果数据
        List<User> userList = new ArrayList<>();
        while (resultSet.next()){
            int id = resultSet.getInt("id");
            String name = resultSet.getString("name");
            int age = resultSet.getInt("age");
            short gender = resultSet.getShort("gender");
            String phone = resultSet.getString("phone");

            User user = new User(id,name,age,gender,phone);
            userList.add(user);
        }

        //5. 释放资源
        statement.close();
        connection.close();


        userList.forEach(System.out::println);
    }

}