SpringBoot实现分页功能

package com.example.demo.mapper;

import com.example.demo.entity.User;

import org.apache.ibatis.annotations.Mapper;

import java.util.List;

Mapper

public interface UserMapper {

     public List<User> findUserByName(String userName);

     public List<User> ListUser();

     public List<User> queryPage(Integer startRows);

     public int getRowCount();

     public int insertUser(User user);

     public int delete( int userId);

     public int Update(User user);

}

<? xml version = "1.0" encoding = "UTF-8" ?>

<!DOCTYPE mapper PUBLIC

         "-//mybatis.org//DTD com.example.Mapper 3.0//EN"

         "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

< mapper namespace = "com.example.demo.mapper.UserMapper" >

     < resultMap id = "result" type = "com.example.demo.entity.User" >

         < result property = "userId" column = "userId" />

   < result property = "userDate" column = "userDate" />

         < result property = "userName" column = "userName" />

         < result property = "userAddress" column = "userAddress" />

     </ resultMap >

     < select id = "ListUser" resultMap = "result" >

   SELECT * FROM user

  </ select >

     < select id = "findUserByName" resultMap = "result" parameterType = "String" >

   SELECT * FROM user

    where userName like concat(concat('%',#{userName}),'%')

    order by userId desc

  </ select >

  < select id = "queryPage" resultMap = "result"   parameterType = "Integer" >

   select * from user

    order by userId desc

    limit #{startRows},5

  </ select >

  < select id = "getRowCount" resultType = "Integer" >

   select count(*) from user

  </ select >

     < insert id = "insertUser" parameterType = "com.example.demo.entity.User" >

   INSERT INTO user

   (

   userId,userDate,userName,userAddress

   )

   VALUES (

   #{userId},

   #{userDate, jdbcType=VARCHAR},

   #{userName, jdbcType=VARCHAR},

   #{userAddress, jdbcType=VARCHAR}

   )

  </ insert >

     < delete id = "delete" parameterType = "int" >

   delete from user where userId=#{userId}

  </ delete >

     < update id = "Update" parameterType = "com.example.demo.entity.User" >

   update user

    set user.userDate=#{userDate},user.userName=#{userName},user.userAddress=#{userAddress}

    where user.userId=#{userId}

  </ update >

</ mapper >

package com.example.demo.service;

import com.example.demo.entity.User;

import com.example.demo.mapper.UserMapper;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import java.util.List;

Service

public class UserService {

     @Autowired

     private UserMapper userMapper;

     public List<User> findByName(String userName) {

         return userMapper.findUserByName(userName);

     }

     public List<User> queryPage(Integer startRows) {

         return userMapper.queryPage(startRows);

     }

     public int getRowCount() {

         return userMapper.getRowCount();

     }

     public User insertUser(User user) {

         userMapper.insertUser(user);

         return user;

     }

     public List<User> ListUser(){

         return userMapper.ListUser();

     }

     public int Update(User user){

         return userMapper.Update(user);

     }

     public int delete( int userId){

         return userMapper.delete(userId);

     }

}

package com.example.demo.controller;

import com.example.demo.entity.User;

import com.example.demo.service.UserService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.*;

import java.util.List;

RestController

public class UserCtrl {

     @Autowired

     private UserService userService;

     @RequestMapping (value = "/delete" , method = RequestMethod.POST)

     public Integer delete(Integer userId) {

         System.out.println(userId);

         int result = userService.delete(userId);

         return result;

     }

     @RequestMapping (value = "/update" , method = RequestMethod.POST)

     @ResponseBody

     public String update(User user) {

         int result = userService.Update(user);

         if (result >= 1 ) {

             return "修改成功" ;

         } else {

             return "修改失败" ;

         }

     }

     @RequestMapping (value = "/insert" , method = RequestMethod.POST)

     public User insert(User user) {

         return userService.insertUser(user);

     }

     @RequestMapping ( "/ListUser" )

     @ResponseBody

     public List<User> ListUser() {

         return userService.ListUser();

     }

     @RequestMapping ( "/ListByName" )

     @ResponseBody

     public List<User> ListUserByName(String userName) {

         return userService.findByName(userName);

     }

     /**

      * 分页

      * @return

      */

     @RequestMapping (value= "/page" )

     @ResponseBody

     public List<User> page(Integer page){

         int pageNow = page == null ? 1 : page;

         int pageSize = 5 ;

         int startRows = pageSize*(pageNow- 1 );

         List<User> list = userService.queryPage(startRows);

         return list;

     }

     /**

      * rows

      * @return

      */

     @RequestMapping (value= "/rows" )

     @ResponseBody

     public int rows(){

         return userService.getRowCount();

     }

}