MyBatis-Plus 实现2种分页方法（QueryWrapper查询分页、SQL查询分页）

爱被打了一巴掌 2022-09-05 00:10 654阅读 0赞

##  1 MyBatisPlusConfig ##

MyBatisPlus配置类。

package com.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.*;
    
    /**
     * MyBatisPlus配置类
     */
    @Configuration
    public class MyBatisPlusConfig {
    
        /**
         * MyBatisPlus拦截器（用于分页）
         */
        @Bean
        public MybatisPlusInterceptor paginationInterceptor() {
            MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
            //添加MySQL的分页拦截器
            interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
            return interceptor;
        }
    }

## 2 UserPagination ##

用户查询条件类。

package com.entity;
    
    import lombok.Data;
    
    /**
     * 查询条件
     */
    @Data
    public class UserPagination {
        /**
         * 当前页号
         */
        private int currentPage;
        /**
         * 每页显示条数
         */
        private int pageSize;
    }

## 3 Mapper ##

### 3.1 UserMapper.java ###

package com.mapper;
    
    import com.baomidou.mybatisplus.core.mapper.BaseMapper;
    import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
    import com.entity.UserEntity;
    import com.entity.UserPagination;
    import org.apache.ibatis.annotations.Mapper;
    
    /**
     * 用户信息dao层
     */
    @Mapper
    public interface UserMapper extends BaseMapper<UserEntity> {
        /**
         * 获取用户信息（SQL查询分页）
         *
         * @param page 分页条件
         * @return
         */
        Page<UserEntity> getUserListBySQLPage(Page<UserEntity> page);
    }

### 3.2 UserMapper.xml ###

<?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.mapper.UserMapper">
        <select id="getUserListBySQLPage" resultType="com.entity.UserEntity">
            SELECT *
            from users
        </select>
    </mapper>

## 4 Service ##

### 4.1 UserService ###

package com.service;
    
    import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
    import com.baomidou.mybatisplus.extension.service.IService;
    import com.entity.*;
    
    
    public interface UserService extends IService<UserEntity> {
        /**
         * 获取用户信息（QueryWrapper查询分页）
         *
         * @param pagination 查询条件
         * @return
         */
        Page<UserEntity> getUserListByQueryWrapperPage(UserPagination pagination);
    
        /**
         * 获取用户信息（SQL查询分页）
         *
         * @param pagination 查询条件
         * @return
         */
        Page<UserEntity> getUserListBySQLPage(UserPagination pagination);
    }

### 4.2 UserServiceImpl ###

package com.service.impl;
    
    import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
    import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
    import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
    import com.entity.*;
    import com.mapper.UserMapper;
    import com.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    @Service
    public class UserServiceImpl extends ServiceImpl<UserMapper, UserEntity> implements UserService {
       @Autowired
       private UserMapper userMapper;
        /**
         * 获取用户信息（QueryWrapper查询分页）
         *
         * @param pagination 查询条件
         * @return
         */
        public Page<UserEntity> getUserListByQueryWrapperPage(UserPagination pagination) {
            QueryWrapper<UserEntity> queryWrapper = new QueryWrapper<>();
            Page<UserEntity> page = new Page<>(pagination.getCurrentPage(), pagination.getPageSize());
            return this.page(page, queryWrapper);
        }
    
        /**
         * 获取用户信息（SQL查询分页）
         *
         * @param pagination 查询条件
         * @return
         */
        @Override
        public Page<UserEntity> getUserListBySQLPage(UserPagination pagination) {
            Page<UserEntity> page = new Page<>(pagination.getCurrentPage(), pagination.getPageSize());
            return userMapper.getUserListBySQLPage(page);
        }
    }

## 5 UserController ##

调试代码。

package com.controller;
    
    import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
    import com.entity.*;
    import com.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.*;
    
    @RestController
    public class UserController {
        @Autowired
        private UserService userService;
    
        /**
         * 获取用户信息（QueryWrapper查询分页）
         *
         * @return
         */
        @GetMapping("/getUserListByQueryWrapperPage")
        public Page<UserEntity> getUserListByQueryWrapperPage(UserPagination pagination) {
            return userService.getUserListByQueryWrapperPage(pagination);
        }
    
        /**
         * 获取用户信息（SQL查询分页）
         *
         * @return
         */
        @GetMapping("/getUserListBySQLPage")
        public Page<UserEntity> getUserListBySQLPage(UserPagination pagination) {
            return userService.getUserListBySQLPage(pagination);
        }
    
    }

## 6 调试结果  ##

### 6.1 QueryWrapper查询分页 ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4OTc0NjM4_size_16_color_FFFFFF_t_70][]

### 6.2 SQL查询分页  ###

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4OTc0NjM4_size_16_color_FFFFFF_t_70 1][]

##  注： ##

更多MyBatis-Plus的配置请查看以下博客。

[Spring Boot 配置MyBatis-Plus（实现查询、新增、更新、删除）][Spring Boot _MyBatis-Plus]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4OTc0NjM4_size_16_color_FFFFFF_t_70]: /images/20220829/a563b97ddb62487990848dc6307be107.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM4OTc0NjM4_size_16_color_FFFFFF_t_70 1]: /images/20220829/c3a26c18c09e420c826b776086af2b3f.png
[Spring Boot _MyBatis-Plus]: https://blog.csdn.net/qq_38974638/article/details/119698988