SpringBoot项目的创建

    4.0.0

    com.haina.springboot
    springboot-02
    1.0-SNAPSHOT


    
        org.springframework.boot
        spring-boot-starter-parent
        2.3.4.RELEASE
    

    
        
            org.springframework.boot
            spring-boot-starter-web
        
        
            org.mybatis.spring.boot
            mybatis-spring-boot-starter
            2.1.3
        
        
            mysql
            mysql-connector-java
            5.1.47
        
        
            com.alibaba
            druid
            1.1.19
        
    


    
        8
        8
    

package com.haina.springboot.controller;

import com.haina.springboot.dao.AdminDao;
import com.haina.springboot.model.Admin;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

@RestController
public class SpringBootController {
    @Resource
    private AdminDao adminDao;

//    RestController和Controller的区别
    

    @RequestMapping("test")
    public String test(){
        Admin admin = adminDao.login("test", "1");
        System.out.println(admin);
        return "asdgasdasd";
    }

}

package com.haina.springboot;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan(basePackages = "com.haina.springboot.dao")
@SpringBootApplication
public class MyApplication {

    public static void main(String[] args) {
        SpringApplication.run(MyApplication.class,args);
        System.out.println("嘿嘿嘿");
    }

}

注意这里的代码严格区分空格数量

server:
  servlet:
    context-path: /springboot
  port: 8081

spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/mybatis_01?serverTimezone=UTC&characterEncoding=UTF-8&useSSL=false
    username: root
    password: root

mybatis:
  mapper-locations: classpath:mappers/*.xml
  type-aliases-package: com.haina.springboot.model

直接通过main方法运行或者在网址栏自行输入路径

1.Mapper配置文件路径存放问题
2.application.yml格式错误
3.导包缺失
4.mysql高版本连接的问题