springBoot使用mybatis-plus插件实现分页过程_Java

一、项目结构

二、pom.xml 依赖添加

（这里我是加在krystal_dao的pom.xml里面，单个项目，直接加在pom.xml，多模块根据自己项目情况添加）

<dependency>
    <groupid>com.baomidou</groupid>
    <artifactid>mybatis-plus</artifactid>
    <version>3.0-beta</version>
</dependency>

三、新建mybatisplusconfig.java

(这里我用专门一个模块添加一些功能代码，里面依赖自己根据报错添加进去即可)

package com.dm.krystal.core.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;

/**
 * @author krystal
 */
@configuration
/*@mapperscan("com.dm.krystal")*/ /*  krystalapiapplication在启动文件上写了，这里不加*/
public class mybatisplusconfig {
    /**
     * mybatis-plus分页插件
     */
    @bean
    public paginationinterceptor paginationinterceptor() {
        paginationinterceptor paginationinterceptor = new paginationinterceptor();
        return paginationinterceptor;
    }
}

四、具体代码实现

1.controller

ipage<examinationpaperrelevancepo>  pagedata = examinationpaperrelevanceservice.getexaminationpaperpagebyqueryvo(page,examinationpaperqueryvo);

2.service

ipage<examinationpaperrelevancepo> getexaminationpaperpagebyqueryvo(page page, examinationpaperqueryvo examinationpaperqueryvo);

3.serviceimp

@override
public ipage<examinationpaperrelevancepo> getexaminationpaperpagebyqueryvo(page page, examinationpaperqueryvo examinationpaperqueryvo) {

    return this.basemapper.getexaminationpaperpagebyqueryvo(page,examinationpaperqueryvo);
}

4.dao

ipage<examinationpaperrelevancepo> getexaminationpaperpagebyqueryvo(page page, @param("examinationpaperqueryvo")examinationpaperqueryvo examinationpaperqueryvo);

5. .xml

 <select id="getexaminationpaperpagebyqueryvo" resulttype="com.eebbk.core.pojo.vo.examinationpapercatalogvo">
        select
        a.id,a.paper_id,a.publisher_id,
        a.publisher_name,a.grade_id,a.grade_name,
        a.semester_id,a.semester_name,
        a.subject_id,a.section_id,a.source_type,
        a.province_id,a.province_name,a.city_id,
        a.city_name,a.`order`,a.staged_type as stagetypeid,a.school_type
        from t_examination_paper_relevance  a
    </select>

五、sql 打印

结果

六、自定义分页（已有100条数据，每次截取十条）

ipage<examinationpaperpo> pagedata = pageutil.listtopage(paperlist,page.getcurrent(),page.getsize());

import com.baomidou.mybatisplus.core.metadata.ipage;
import com.baomidou.mybatisplus.extension.plugins.pagination.page;
import lombok.extern.slf4j.slf4j;

import java.util.arraylist;
import java.util.list;
import java.util.concurrent.atomic.longaccumulator;

@slf4j
public class pageutil {


    public static <t> ipage<t> listtopage(list<t> list, long pagenum, long pagesize){
        ipage<t> ipage = new page<>(pagenum,pagesize);
        ipage.settotal(list.size());
        int startindex = (int)((pagenum - 1) * pagesize);
        if(null == list || list.isempty() || startindex > list.size()){
            ipage.setrecords(new arraylist<>());
        }
        else {
            int toindex = (int)(pagenum * pagesize);
            ipage.setrecords(list.sublist(startindex,toindex > list.size() ? list.size() : toindex));
        }
        return ipage;
    }
}