SpringBoot+MyBatis-Plus实现分页的项目实践

    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>mybatis-plus-boot-starter</artifactId>
        <version>3.5.7</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.33</version>
    </dependency>

spring:
    #配置数据源
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/maven?serverTimezone=Asia/Shanghai&characterEncoding=utf8&useUnicode=true&useSSL=false
    username: root
    password: 123456
mybatis-plus:
  configuration:
    #开启驼峰映射
    map-underscore-to-camel-case: true
    #开启日志，方便观察SQL执行语句
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

@TableName(value = "student")//对应数据库表名
@TableId(type = IdType.AUTO)//对应数据库主键，并设置类型为自增
@TableField(value = "id") //对应数据库字段名
@TableField(exist = false)//设置表中不存在的字段
@TableLogic(value = "默认值",delval = "删除后默认值")//逻辑删除时用的字段
@Version//作用：在使用 MyBatis-Plus 乐观锁插件时使用

package com.apesource.spring_mybatis_plus_01.config;

import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * @author 崔世博
 * @version 1.0
 * @since 2024/9/20
 */
@Configuration
public class PageConfig {

    //注入mp拦截器
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor() {
        //1.实例化拦截器
        MybatisPlusInterceptor mybatisPlusInterceptor = new MybatisPlusInterceptor();
        //2.添加分页拦截器
        mybatisPlusInterceptor.addInnerInterceptor(new PaginationInnerInterceptor());
        return mybatisPlusInterceptor;
    }
}

SELECT stu_id,stu_name,nick_name,stu_age,is_delete FROM student WHERE is_delete=0 LIMIT 3

   @Test
    public void show6() {
        //分页
        Page<Student> page = new Page<Student>();
        //1.定义分页规则
        page.setSize(3);        //页面容量
        page.setCurrent(1);     //当前页码


        Page<Student> studentPage = studentMapper.selectPage(page, null);

        //分页结果
        List<Student> list = studentPage.getRecords();
        System.out.println("总页数：" + studentPage.getPages());
        System.out.println("总记录数：" + studentPage.getTotal());
        list.forEach(System.out::println);

    }

SELECT stu_id,stu_name,nick_name,stu_age,is_delete FROM student WHERE is_delete=0 AND (stu_age = 20) LIMIT 3

    @Test
    public void show6() {
        //分页
        Page<Student> page = new Page<Student>();
        //1.定义分页规则
        page.setSize(3);        //页面容量
        page.setCurrent(1);     //当前页码

        //查询条件(选填)
        QueryWrapper<Student> qr = new QueryWrapper<Student>();
        qr.eq("stu_age", 20);

        Page<Student> studentPage = studentMapper.selectPage(page, qr);

        //分页结果
        List<Student> list = studentPage.getRecords();
        System.out.println("总页数：" + studentPage.getPages());
        System.out.println("总记录数：" + studentPage.getTotal());
        list.forEach(System.out::println);

    }

SELECT stu_id,stu_name,nick_name,stu_age,is_delete FROM student WHERE is_delete=0 AND (stu_age > 18) LIMIT 3

   @Test
    public void show6() {
        //分页
        Page<Student> page = new Page<Student>();
        //1.定义分页规则
        page.setSize(3);        //页面容量
        page.setCurrent(1);     //当前页码

        LambdaQueryWrapper<Student> lambdaQueryWrapper = new LambdaQueryWrapper<>();
        lambdaQueryWrapper.gt(Student::getStuAge, 18);

        Page<Student> studentPage = studentMapper.selectPage(page, lambdaQueryWrapper);

        //分页结果
        List<Student> list = studentPage.getRecords();
        System.out.println("总页数：" + studentPage.getPages());
        System.out.println("总记录数：" + studentPage.getTotal());
        list.forEach(System.out::println);

    }