首先是相关的pom文件如下

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <parent>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-starter-parent</artifactId>
      <version>2.7.3</version>
      <!--<version>2.2.2.RELEASE</version>-->
      <relativePath/> <!-- lookup parent from repository -->
   </parent>
   <groupId>com.ext</groupId>
   <artifactId>demotest1</artifactId>
   <version>0.0.1-SNAPSHOT</version>
   <name>demotest1</name>
   <description>Demo project for Spring Boot</description>
   <properties>
      <java.version>1.8</java.version>
   </properties>
   <dependencies>
      <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-thymeleaf</artifactId>
      </dependency>
      <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
      </dependency>

      <dependency>
         <groupId>mysql</groupId>
         <artifactId>mysql-connector-java</artifactId>
         <scope>runtime</scope>
      </dependency>

      <dependency>
         <groupId>org.mybatis</groupId>
         <artifactId>mybatis-typehandlers-jsr310</artifactId>
         <version>1.0.1</version>
      </dependency>

      <dependency>
         <groupId>org.projectlombok</groupId>
         <artifactId>lombok</artifactId>
         <optional>true</optional>
      </dependency>
      <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-test</artifactId>
         <scope>test</scope>
      </dependency>

      <!--<dependency>-->
         <!--<groupId>org.mybatis</groupId>-->
         <!--<artifactId>mybatis-spring</artifactId>-->
         <!--<version>2.0.5</version>-->
      <!--</dependency>-->


      <dependency>
         <groupId>org.mybatis.spring.boot</groupId>
         <artifactId>mybatis-spring-boot-starter</artifactId>
         <version>2.1.1</version>
      </dependency>

   </dependencies>

   <build>
      <plugins>
         <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <configuration>
               <excludes>
                  <exclude>
                     <groupId>org.projectlombok</groupId>
                     <artifactId>lombok</artifactId>
                  </exclude>
               </excludes>
            </configuration>
         </plugin>
         <!--加上这个是为了防止出现maven打包错误-如果使用2.2.2 哪个版本不用加下面的不会报错使用最新的必须加这个->  
         <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-resources-plugin</artifactId>
            <version>3.1.0</version>
         </plugin>

      </plugins>
   </build>

</project>

然后是相关的mapper接口代码入下面

package com.ext.demotest1.mapper;

import com.ext.demotest1.entity.User;
import org.apache.ibatis.annotations.Delete;
import org.apache.ibatis.annotations.Insert;
import org.apache.ibatis.annotations.Select;
import org.apache.ibatis.annotations.Update;
import org.springframework.stereotype.Repository;

import java.util.List;

@Repository
public interface UserMapper {

    @Insert("insert into User(number,name,age,department,proid)values(#{number},#{name},#{age},#{department},#{proid})")
    public  void add(User user);

    @Delete("delete from User where id = #{id}")
    public void delete(int id);

    @Update("update User set name=#{name},number= #{number},age= #{age},department = #{department} where id = #{id}")
    public void update(User user);

    @Select("select * from User where id > 1")
    public List<User>getListAll();
}

下面的是service的代码

package com.ext.demotest1.service;

import com.ext.demotest1.entity.User;
import com.ext.demotest1.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class UserService {
    @Autowired
    UserMapper mapper;

    public  void add(User user){
        mapper.add(user);
    }

    public void delete(int id){
        mapper.delete(id);
    }

    public void update(User user){
        mapper.update(user);
    }

    public List<User> getListAll(){
        return  mapper.getListAll();
    }
}

然后是controller层的代码

package com.ext.demotest1.controller;

import com.ext.demotest1.entity.User;
import com.ext.demotest1.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserService service;

    @GetMapping("/add")
    public String add(){
        User user = new User();
        user.setAge(10);
        user.setDepartment("123");
        user.setName("aa");
        //user.setNumber("001");
        //user.setProid(1);
        service.add(user);
        return "success";
    }
    @GetMapping("/delete")
    public String delete(int id){
        service.delete(id);
        return "success";
    }

    @GetMapping("/update")
    public String update(){
        User user = new User();
        user.setId(2);
        user.setNumber("0003");
        user.setName("name");
        user.setAge(15);
        user.setDepartment("nianjizu");
        service.update(user);
        return "success";
    }

    @GetMapping("/all")
    public List<User> getAll(){
        List<User> list = service.getListAll();
        return list;
    }
}

实体类的User如下

package com.ext.demotest1.entity;

import lombok.Data;

@Data
public class User {
    private  int id;
    private  String number;
    private  String name;
    private  String department;
    private int age;
    private int proid;
}

配置文件的代码如下

server:
  port: 8051
  tomcat:
    max-http-header-size: 8192
    uri-encoding: utf-8
spring:
  datasource:
    url: jdbc:mysql://localhost:3306/testone?characterEncoding=utf-8&useSSL=false&useUnicode=true&autoReconnect=true  # MySQL高版本已经不需要填写serverTimezone=CTT
    username: root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver