第三章：【springboot】框架介绍MyBatis

MyBatis

概述：MyBatis 是一款优秀的持久层(三层架构中的dao层)框架，用来简化jdbc的开发.

配置

导入依赖

<!--pom.xml-->
<!--        mybatis起步依赖-->
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>3.5.14</version>
</dependency>
        <!--        mysql驱动包-->
<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</artifactId>
<scope>runtime</scope>
</dependency>

配置数据库连接的四要素

#配置数据库连接信息 四要素
#驱动类名称
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
#数据库连接的url
spring.datasource.url=jdbc:mysql://localhost:3306/mydb01
#数据库连接的用户名
spring.datasource.username=root
#数据库连接的密码
spring.datasource.password=123456

新建Mapper接口

package com.springboot.Mapper;

import com.springboot.Pojo.MyUser;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

@Mapper //在运行时，会自动生成该接口的实现类对象（代理对象），并且将该对象交给IOC容器管理
public interface UserMapper {
    //查询全部用户信息
    @Select("select * from user")
    public List<MyUser> listUser();
}

使用javaBean类来结束数据库表

package com.springboot.Pojo;


public class MyUser {
    private int id;
    private String name;
    private String password;
    private String createTime;
    private String updateTime;
    private Short status;

    public MyUser() {
    }

    public MyUser(int id, String name, String password, String createTime, String updateTime, Short status) {
        this.id = id;
        this.name = name;
        this.password = password;
        this.createTime = createTime;
        this.updateTime = updateTime;
        this.status = status;
    }

    @Override
    public String toString() {
        return "MyUser{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", password='" + password + '\'' +
                ", createTime=" + createTime +
                ", updateTime=" + updateTime +
                ", status=" + status +
                '}';
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getCreateTime() {
        return createTime;
    }

    public void setCreateTime(String createTime) {
        this.createTime = createTime;
    }

    pub