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MyBatis Plus分页时怎么实现排序

发表于:2022-11-28 作者:安全数据网编辑
编辑最后更新 2022年11月28日,本篇内容主要讲解"MyBatis Plus分页时怎么实现排序",感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷,实用性强。下面就让小编来带大家学习"MyBatis Plus分页时怎么实现排序"吧!

本篇内容主要讲解"MyBatis Plus分页时怎么实现排序",感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷,实用性强。下面就让小编来带大家学习"MyBatis Plus分页时怎么实现排序"吧!

简介

分页时排序的方法

  • 后端OrderItems排序

  • 后端Wrapper排序

  • 前端指定排序

排序涉及到的类

排序涉及到Page类的List orders;成员,OrderItem定义如下:

public class OrderItem implements Serializable {    private static final long serialVersionUID = 1L;     //需要进行排序的字段    private String column;    // 是否正序排列,默认 true    private boolean asc = true;    ...}

建库建表

DROP DATABASE IF EXISTS mp;CREATE DATABASE mp DEFAULT CHARACTER SET utf8;USE mp; DROP TABLE IF EXISTS `t_user`;SET NAMES utf8mb4;CREATE TABLE `t_user`(    `id`           BIGINT(0) NOT NULL AUTO_INCREMENT,    `user_name`    VARCHAR(64) NOT NULL COMMENT '用户名(不能重复)',    `nick_name`    VARCHAR(64) NULL COMMENT '昵称(可以重复)',    `email`        VARCHAR(64) COMMENT '邮箱',    `create_time`  DATETIME(0) NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',    `update_time`  DATETIME(0) NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '修改时间',    `deleted_flag` BIGINT(0) NOT NULL DEFAULT 0 COMMENT '0:未删除 其他:已删除',    PRIMARY KEY (`id`) USING BTREE,    UNIQUE KEY `index_user_name_deleted_flag` (`user_name`, `deleted_flag`),    KEY `index_create_time`(`create_time`)) ENGINE = InnoDB COMMENT = '用户';INSERT INTO `t_user` VALUES (1, 'knife', '刀刃', 'abc@qq.com', '2021-01-23 09:33:36', '2021-01-23 09:33:36', 0);INSERT INTO `t_user` VALUES (2, 'sky', '天蓝', '123@qq.com', '2021-01-24 18:12:21', '2021-01-24 18:12:21', 0);

执行后的结果:

依赖

pom.xml

    4.0.0            org.springframework.boot        spring-boot-starter-parent        2.3.12.RELEASE                 com.example    MyBatis-Plus_Simple    0.0.1-SNAPSHOT    MyBatis-Plus_Simple    Demo project for Spring Boot             1.8                            org.springframework.boot            spring-boot-starter-web                    com.baomidou            mybatis-plus-boot-starter            3.5.1            spring-boot-starter-test            test            mysql            mysql-connector-java            org.projectlombok            lombok            com.github.xiaoymin            knife4j-spring-boot-starter            3.0.3                                            org.springframework.boot                spring-boot-maven-plugin                        

配置

application.yml

spring:  datasource:    driver-class-name: com.mysql.cj.jdbc.Driver    url: jdbc:mysql://127.0.0.1:3306/mp?characterEncoding=UTF-8&serverTimezone=Asia/Shanghai    username: root    password: 222333 #mybatis-plus配置控制台打印完整带参数SQL语句mybatis-plus:  configuration:    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

分页插件的配置(必须)

package com.example.demo.config;import com.baomidou.mybatisplus.annotation.DbType;import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import com.baomidou.mybatisplus.extension.plugins.inner.PaginationInnerInterceptor;@Configurationpublic class MyBatisPlusConfig {    /**     * 分页插件     */    @Bean    public MybatisPlusInterceptor mybatisPlusInterceptor() {        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));        return interceptor;    }}

代码

Entity

package com.example.demo.user.entity; import com.baomidou.mybatisplus.annotation.IdType;import com.baomidou.mybatisplus.annotation.TableId;import com.baomidou.mybatisplus.annotation.TableLogic;import com.baomidou.mybatisplus.annotation.TableName;import com.baomidou.mybatisplus.extension.activerecord.Model;import lombok.Data;import java.time.LocalDateTime;@Data@TableName(value = "t_user")public class User {    @TableId(value = "id", type = IdType.AUTO)    private Long id;    /**     * 用户名(不能重复)     */    private String userName;     * 昵称(可以重复)    private String nickName;     * 邮箱    private String email;     * 创建时间    private LocalDateTime createTime;     * 修改时间    private LocalDateTime updateTime;     * 0:未删除 其他:已删除    @TableLogic(delval = "id")    private Long deletedFlag;}

Service

接口

package com.example.demo.user.service; import com.baomidou.mybatisplus.extension.service.IService;import com.example.demo.user.entity.User;public interface UserService extends IService {}

实现

package com.example.demo.user.service.impl; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;import com.example.demo.user.entity.User;import com.example.demo.user.mapper.UserMapper;import com.example.demo.user.service.UserService;import org.springframework.stereotype.Service;@Servicepublic class UserServiceImpl extends ServiceImpl implements UserService {}

Controller

package com.example.demo.user.controller; import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;import com.baomidou.mybatisplus.core.metadata.IPage;import com.baomidou.mybatisplus.core.metadata.OrderItem;import com.baomidou.mybatisplus.core.toolkit.Wrappers;import com.baomidou.mybatisplus.extension.plugins.pagination.Page;import com.example.demo.user.entity.User;import com.example.demo.user.service.UserService;import io.swagger.annotations.Api;import io.swagger.annotations.ApiOperation;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.GetMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import java.util.List;@Api(tags = "排序")@RestController@RequestMapping("sort")public class SortController {    @Autowired    private UserService userService;    @ApiOperation("默认顺序")    @GetMapping("defaultOrder")    public IPage defaultOrder(Page page) {        return userService.page(page);    }    @ApiOperation("通过orderItems")    @GetMapping("orderItems")    public IPage orderItems(Page page) {        page.addOrder(OrderItem.desc("create_time"));        // 可以指定多列。比如下边这个:按create_time排序,若create_time相同,则按id排序        // page.addOrder(OrderItem.desc("create_time"), OrderItem.asc("id"));    @ApiOperation("通过wrapper")    @GetMapping("wrapper")    public IPage wrapper(Page page) {        LambdaQueryWrapper queryWrapper = Wrappers.lambdaQuery();        // 按create_time排序,若create_time相同,则按id排序        queryWrapper.orderByDesc(User::getCreateTime);        queryWrapper.orderByAsc(User::getId);        return userService.page(page, queryWrapper);    @ApiOperation("前端指定顺序")    @GetMapping("byFrontEnd")    public IPage byFrontEnd(Page page) {}

测试

访问Knife4j页面:http://localhost:8080/doc.html

1.不指定顺序

本处前端不传任何参数进行的测试。

2.后端OrderItem排序(create_time倒序)

本处前端不传任何参数进行的测试。

3.后端Wrapper排序(create_time倒序,id升序)

本处前端不传任何参数进行的测试。

4.前端指定排序(create_time倒序)

前端指定orders[0].asc和orders[0].column

结果:

到此,相信大家对"MyBatis Plus分页时怎么实现排序"有了更深的了解,不妨来实际操作一番吧!这里是网站,更多相关内容可以进入相关频道进行查询,关注我们,继续学习!

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