springboot快速整合mybatis连接mysql

1、新建一个springboot项目

2、选择需要的依赖，然后等待依赖的下载完成

 

3、快速配置application.properties文件

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=123
spring.datasource.url=jdbc:mysql://localhost:3306/hello

mybatis.mapper-locations=classpath:mapper/*.xml   //实现mapper接口配置

4、新建6个文件夹以及在文件夹下创建文件        

 

5、编写entity-Person

package com.example.entity;

import lombok.Data;

@Data
public class Person {
    private String name;       //这里的属性和数据库表的字段一致
    private String age;
}

6、编写mapper文件

PersonMapper.java

package com.example.mapper;

import com.example.entity.Person;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface PersonMapper {
    Person getPerson();
}

personMapper.xml 

    
        select * from person
    

7、编写Service PersonService.java

package com.example.service;

import com.example.entity.Person;

public interface PersonService {
    Person getPerson();
}

 PersonServiceImpl.java

package com.example.service.Impl;

import com.example.entity.Person;
import com.example.mapper.PersonMapper;
import com.example.service.PersonService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class PersonServiceImpl implements PersonService {

    @Autowired
    private PersonMapper personMapper;

    @Override
    public Person getPerson() {
        Person person = personMapper.getPerson();
        return person;
    }
}

8、编写controller Controller.java

package com.example.controller;

import com.example.entity.Person;
import com.example.service.PersonService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class PersonController {

    @Autowired
    private PersonService personService;

    @GetMapping("")
    public Person getPerson(){
        Person person = personService.getPerson();
        return person;
    }

}

9、启动项目访问地址即可

10、注意事项 

各个类的注解需要检查是否齐全数据库url可以先使用idea右侧的Database测试一下是否连接成功数据库的名称配置项是username而不是name,曾经因为这个找不不少时间！！！