前言

Mybatis-Plus（简称MP）是一个 Mybatis 的增强工具，在 Mybatis 的基础上只做增强不做改变，为简化开发、提高效率而生。
链接: Mybatis-Plus官网地址

准备数据库表

执行SQL文件创建表添加数据

CREATE TABLE user
(
    id BIGINT(20) NOT NULL COMMENT '主键ID',
    name VARCHAR(30) NULL DEFAULT NULL COMMENT '姓名',
    age INT(11) NULL DEFAULT NULL COMMENT '年龄',
    email VARCHAR(50) NULL DEFAULT NULL COMMENT '邮箱',
    PRIMARY KEY (id)
);

INSERT INTO user (id, name, age, email) VALUES
(1, 'Jone', 18, 'test1@baomidou.com'),
(2, 'Jack', 20, 'test2@baomidou.com'),
(3, 'Tom', 28, 'test3@baomidou.com'),
(4, 'Sandy', 21, 'test4@baomidou.com'),
(5, 'Billie', 24, 'test5@baomidou.com');

引入依赖

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.4.1</version>
        </dependency>

配置文件

配置数据源：

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/test?characterEncoding=utf8
    username: root
    password: admin
    driver-class-name: com.mysql.jdbc.Driver

实体类代码

package com.gavin.boot.domain;

import lombok.Data;

@Data
public class User {

    private Long id;
    private String name;
    private Integer age;
    private String email;
}

mapper接口代码

package com.gavin.boot.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.gavin.boot.domain.User;

import java.util.List;

@Mapper
public interface UserMapper extends BaseMapper<User> {

    List<User> selectPageVo(IPage<User> page);
}

service接口代码

package com.gavin.boot.service;

import com.baomidou.mybatisplus.extension.service.IService;
import com.gavin.boot.domain.User;

public interface UserService extends IService<User> {

}

service实现类代码

package com.gavin.boot.service.impl;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.gavin.boot.domain.User;
import com.gavin.boot.mapper.UserMapper;
import com.gavin.boot.service.UserService;
import org.springframework.stereotype.Service;

@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {
    
}

controller类代码

实现User表的分页查询

package com.gavin.boot.controller;

import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.gavin.boot.domain.User;
import com.gavin.boot.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import java.util.List;

@Controller
public class UserController {

    @Autowired
    private UserService userService;

    @GetMapping("/getUserList")
    @ResponseBody
    public List<User> getUserList() {
        Page<User> userPage = new Page<>();
        //当前页
        userPage.setCurrent(1);
        //每页条数
        userPage.setSize(2);
        Page<User> page = userService.page(userPage);
        List<User> list = page.getRecords();
        return list;
    }
}