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

目录

•  1 MyBatisPlusConfig
• 2 UserPagination
• 3 Mapper
• 3.1 UserMapper.java
• 3.2 UserMapper.xml
• 4 Service
• 4.1 UserService
• 4.2 UserServiceImpl
• 5 UserController
• 6 调试结果 
• 6.1 QueryWrapper查询分页
• 6.2 SQL查询分页 

 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

6.2 SQL查询分页 

 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）