SpringBoot Mybatis分页查询功能。
Mybatis是自带分页查询功能的哟。就不用自己再写一大堆算法实体类啥的，不多说直接上代码，并且我可愿意保证是100%能测试的哟。
1. 首先我们需要配置Mybatis的插件环境。
（1）在pom.xml里面拉Jar包：
com.github.pagehelper
pagehelper-spring-boot-starter
${pagehelper-spring-boot.version}
（2）在application.properties配置里面设置：
pagehelper.helperDialect=mysql
pagehelper.reasonable=true
pagehelper.supportMethodsArguments=true
pagehelper.params=count=countSql（3）下面直接开始写数据层与逻辑层，实体类如下：
package com.demo.model;
import java.math.BigDecimal;
import java.util.List;
import java.util.Map;
//商品表实体类;
public class Commodity {
public int cid; //商品id;
public BigDecimal cprice; //商品价格;
public String ccode; //商品编码;
public int ctype; //商品类型;
public String cname; //商品名称;
public ComType tid;
public ComType tname;
public int countx; //商品数量;
public Commodity(Commodity g, int i) {
// TODO Auto-generated constructor stub
}
public Commodity(){}
/*public Commodity(Map g, int i) {
// TODO Auto-generated constructor stub
}*/
public Commodity(Commodity g) {
// TODO Auto-generated constructor stub
}
public Commodity(Map g, int i) {
// TODO Auto-generated constructor stub
}
public ComType getTid() {
return tid;
}
public void setTid(ComType tid) {
this.tid = tid;
}
public ComType getTname() {
return tname;
}
public void setTname(ComType tname) {
this.tname = tname;
}
public int getCountx() {
return countx;
}
public void setCountx(int countx) {
this.countx = countx;
}
@Override
public String toString() {
return "Commodity [cid=" + cid + ", cprice=" + cprice + ", ccode=" + ccode + ", ctype=" + ctype + ", cname=" + cname
+ ", tid=" + tid + ", tname=" + tname + ", countx=" + countx + "]";
}
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getCname() {
return cname;
}
public void setCname(String cname) {
this.cname = cname;
}
public BigDecimal getCprice() {
return cprice;
}
public void setCprice(BigDecimal cprice) {
this.cprice = cprice;
}
public String getCcode() {
return ccode;
}
public void setCcode(String ccode) {
this.ccode = ccode;
}
public int getCtype() {
return ctype;
}
public void setCtype(int ctype) {
this.ctype = ctype;
}
}
（4）Dao层如下：
package com.demo.mapper;
import java.util.List;
import org.apache.ibatis.annotations.Mapper;
import com.demo.model.Commodity;
import com.demo.utils.Page;
@Mapper
public interface CommodityDao{
//主页展示商品查询;
public List comSelect();
}
（5）Service层如下：
package com.demo.service;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import com.demo.mapper.CommodityDao;
import com.demo.model.Commodity;
import com.demo.model.Result;
import com.demo.utils.Page;
@Service
public class CommodityService {
@Resource
private CommodityDao comm;
/**
* 商品页面展示查询;
* @return
* @throws Exception
*/
public List comServiceSelect()throws Exception{
List list=comm.comSelect();
return list;
}
}
（6）controller控制层也就是Action层如下：
package com.demo.controller;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.request;
import java.math.BigDecimal;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import com.demo.model.Commodity;
import com.demo.model.Login;
import com.demo.model.Order;
import com.demo.model.Result;
import com.demo.model.Sex;
import com.demo.service.CommodityService;
import com.demo.service.LoginService;
import com.demo.service.OrderService;
import com.demo.service.SexService;
import com.demo.utils.Page;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
@Controller
@RequestMapping("/")
public class SpringBootUsersController {
@Autowired
private CommodityService comm;
@RequestMapping("/findCommodityAction_1")
public String findCommodityAction_1(@RequestParam(defaultValue = "1",value = "pageNum")Integer pageNum,Integer pageSize,HttpServletRequest request,HttpServletResponse respoes)throws Exception{
//分页插件;
//这个里面是两个参数：pageNum(当前页数)与pageSize(每页要显示的数据数)，这里直接给它们初始值为：pageNum=1，pageSize=4;
PageHelper.startPage(pageNum,4);
//获取数据;
List list=comm.comServiceSelect();
//然后把查询出来的数据放到插件自带的PageInfo对象里面;
PageInfo pageInfo = new PageInfo(list);
request.setAttribute("list",pageInfo);
return "text";
}
}
（7）sql.xml其实数据库sql语句跟平时一样没区别如下：
（8）视图层也就是页面如下：
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn"%>
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="form" %>
<%@ taglib uri="http://www.springframework.org/tags" prefix="spring" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
My JSP 'text.jsp' starting page
（10）效果图如下：
