一 创建项目，选择spring boot 初始化，配置相关信息

 

第五步创建实体类

二  快速开发实体类的jar包--lombok

<dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>

使用：

@Data
public class User {
    private Long id;
    private String name;
    private String password;
    private Integer age;
    private String tel;
}

三 标准层crud方法

进行对比：

四 mp拦截器实现分页

//添加配置类，让springboot启动类扫描到这个类
@Configuration
public class MpConfig {
    @Bean
    public MybatisPlusInterceptor mpInterceptor(){
        //1.定义Mp拦截器
        MybatisPlusInterceptor mpInterceptor = new MybatisPlusInterceptor();
        //2.添加具体的拦截器
        mpInterceptor.addInnerInterceptor(new PaginationInnerInterceptor());
        return mpInterceptor;
    }
}

 测试代码：

 @Test
    void testGetByPage(){
        //IPage对象封装了分页操作相关的数据
        IPage page  = new Page(2,3);
        userDao.selectPage(page,null);
        System.out.println("当前页码值："+page.getCurrent());
        System.out.println("每页显示数："+page.getSize());
        System.out.println("一共多少页："+page.getPages());
        System.out.println("一共多少条数据："+page.getTotal());
        System.out.println("数据："+page.getRecords());
    }

开启mp的日志，输出到控制台

mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

结果： 

JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@706fe5c6] will not be managed by Spring
==>  Preparing: SELECT COUNT(*) FROM user   //原始sql语句
==> Parameters:  //参数列表
<==    Columns: COUNT(*)
<==        Row: 4
<==      Total: 1
==>  Preparing: SELECT id,name,password,age,tel FROM user LIMIT ?,?  //追加的
==> Parameters: 3(Long), 3(Long)
<==    Columns: id, name, password, age, tel
<==        Row: 1713551068175183874, 程序员, mycobi, 12, 4006184000
<==      Total: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@444cc791]