MyBatisPlus--分页插件

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MyBatisPlus自带分页插件

MyBatis Plus自带分页插件，只要简单的配置即可实现分页功能

添加配置类或在启动类中配置分页插件

创建配置类方式:

package com.qcby.mybatisPlus.config;

import com.baomidou.mybatisplus.annotation.DbType;
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;

@Configuration
public class MybatisPlusConfig {
	@Bean
	public MybatisPlusInterceptor mybatisPlusInterceptor(){
		MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
		//添加分页插件
		interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
		return interceptor;
	}
}

启动类中配置分页插件方式(推荐):

@SpringBootApplication
@MapperScan("com.qcby.mybatisPlus.mapper")
public class MybatisPlusdemo01 {

	public static void main(String[] args) {
		SpringApplication.run(MybatisPlusdemo01.class, args);
	}

	@Bean
	public MybatisPlusInterceptor mybatisPlusInterceptor(){
		MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
		//添加分页插件
		interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
		return interceptor;
	}
}

测试

package com.qcby.mybatisPlus;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.qcby.mybatisPlus.mapper.UserMapper;
import com.qcby.mybatisPlus.model.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

import java.util.List;

@SpringBootTest
public class MybatisPlusPageTest {

    @Autowired
    private UserMapper userMapper;

    @Test
    public void testPage() {
        //设置分页参数
        Page<User> page = new Page<>(1, 5);
        userMapper.selectPage(page,null);
        //获取分页数据
        List<User> list = page.getRecords();
        list.forEach(System.out::println);
        System.out.println("MyBatisPlus自带分页插件");
        System.out.println("当前页："+page.getCurrent());
        System.out.println("每页显示的条数："+page.getSize());
        System.out.println("总记录数："+page.getTotal());
        System.out.println("总页数："+page.getPages());
        System.out.println("是否有上一页："+page.hasPrevious());
        System.out.println("是否有下一页："+page.hasNext());
    }
}

自定义分页

在UserMapper中定义接口方法

public interface UserMapper extends BaseMapper<User> {

    /**
     * 根据年龄查询用户列表，分页显示
     * @param page 分页对象 ,xml中可以从里面进行取值 ,传递参数 Page 即自动分页 ,必须放在第一位
     * @param age 年龄
     * @return
     */
    IPage<User> selectPageVo(@Param("page") Page<User> page, @Param("age") Integer age);
}

UserMapper.xml中编写SQL

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.qcby.mybatisPlus.mapper.UserMapper">

    <!-- 定义基础字段 SQL 片段 -->
    <sql id="BaseColumns">
        uid, username, age, email
    </sql>

    <!-- 自定义分页查询 -->
    <!--IPage<User> selectPageVo(Page<User> page, Integer age);-->
    <select id="selectPageVo" resultType="com.qcby.mybatisPlus.model.User">
        SELECT
        <include refid="BaseColumns"></include>
        FROM t_user
        WHERE age > #{age}
    </select>

</mapper>

测试

@Test
    public void testSelectPageVo() {
        //设置分页参数
        Page<User> page = new Page<>(1, 5);
        userMapper.selectPageVo(page,20);
        //获取分页数据
        List<User> list = page.getRecords();
        list.forEach(System.out::println);
        System.out.println("自定义分页");
        System.out.println("当前页："+page.getCurrent());
        System.out.println("每页显示的条数："+page.getSize());
        System.out.println("总记录数："+page.getTotal());
        System.out.println("总页数："+page.getPages());
        System.out.println("是否有上一页："+page.hasPrevious());
        System.out.println("是否有下一页："+page.hasNext());
    }