MybatisPlus分页条件查询

前提：先导入MybatisPlus相关依赖

1、配置分页插件（不需要修改）

PaginationInterceptor

package com.wagn.s.config;

import com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class PageConfig {
    /**
     * 分页插件
     */
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        return new PaginationInterceptor();
    }
}

2、将查询条件封装成类

package com.wagn.s.vo;

import lombok.Data;

@Data
public class VoQuery {
    private String name;
    private String gender;
}

3、接口使用get请求，传入需要的参数
query接口

package com.wagn.s.controller;


import com.wagn.s.entity.UserTable;
import com.wagn.s.service.UserTableService;
import com.wagn.s.vo.VoQuery;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.nio.file.Watchable;
import java.util.List;

/**
 * <p>
 *  前端控制器
 * </p>
 *
 * @author testjava
 * @since 2020-09-12
 */
@RestController
@RequestMapping("/s/user-table")
public class UserTableController {

    @Autowired
    private UserTableService userTableService;

    @GetMapping("query/{current}/{limit}")
    public List<UserTable> query(@PathVariable Long current, @PathVariable Long limit,
                                 VoQuery voQuery){
        //current为当前页，limit为每页显示个数，voQuery为封装的查询条件
        List<UserTable> rs = userTableService.myquery(current,limit,voQuery);
        return rs;
    }

}

4、获得条件后，执行多条件分页查询
myquery()方法

package com.wagn.s.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.wagn.s.entity.UserTable;
import com.wagn.s.mapper.UserTableMapper;
import com.wagn.s.service.UserTableService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.wagn.s.vo.VoQuery;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.util.List;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author testjava
 * @since 2020-09-12
 */
@Service
public class UserTableServiceImpl extends ServiceImpl<UserTableMapper, UserTable> implements UserTableService {

    @Autowired
    private UserTableService userTableService;
    @Override
    public List<UserTable> myquery(Long current, Long limit, VoQuery voQuery) {


        //初始化page
        Page<UserTable> page = new Page<>(current,limit);

        //设置条件
        QueryWrapper<UserTable> wrapper =new QueryWrapper<>();
        //eq是等于，ge是大于等于，gt是大于，le是小于等于，lt是小于，like是模糊查询
        
        if(!StringUtils.isEmpty(voQuery.getName())){
            wrapper.like("name",voQuery.getName());
        }
        if(!StringUtils.isEmpty(voQuery.getGender())) {
            wrapper.eq("gender", voQuery.getGender());
        }

        //执行查询
        userTableService.page(page,wrapper);


        long total = page.getTotal();//总数
        List<UserTable> rs = page.getRecords();//结果
        return rs;
    }
}

（5、控制台查看底层执行的SQL）
配置属性

mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

按照以上配置后MyBatis-Plus分页后total和pages总为0，需要添加添加MyBatis-Plus分页的配置：

注意新版配置和老版配置有区别：

老版本：

@Configuration
public class MybatisPlusConfig {
    /**
     * mybatis-plus分页插件
     * @return
     */
    @Bean
    public PaginationInterceptor paginationInterceptor(){
        PaginationInterceptor page = new PaginationInterceptor();
        return page;
    }
}

新版本：

@Configuration
public class MyBatisPlusConfig {
 
    @Bean
    public MybatisPlusInterceptor mybatisPlusInterceptor(){
        MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
        interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
        return interceptor;
    }
 
}