SpringBoot---------整合Mybatis

第一步：首先引入依赖

        //mysql依赖
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

       //mybatis依赖
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.3.1</version>
        </dependency>

       //德鲁伊druid数据源依赖
        <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid-spring-boot-starter</artifactId>
                <version>1.2.6</version>
        </dependency>

第二步：连接数据库

 我这里使用的是安装在Linux中的Mysql，与在Windows上的操作是一样的

第三步：配置application.yml文件

spring:
  datasource:
    //配置mysql
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://192.168.136.132/mydb
    username: root
    password: 1234

    //配置Druid数据源
    type: com.alibaba.druid.pool.DruidDataSource

第四步：开始编码实现

 这里我便于快速开发，只写了Controller层和Mapper层，Service层一般用于数据处理，暂时先不写，实体类的话这里也不做展示，很简单

 Controller层：

package com.example.springboot_learn.Controller;

import com.example.springboot_learn.ApplicationData;
import com.example.springboot_learn.JsonResult;
import com.example.springboot_learn.Pojo.Book;
import com.example.springboot_learn.Pojo.Student;
import org.springframework.beans.factory.annotation.Autowired;
import com.example.springboot_learn.mapper.studentmapper;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
public class BookController {

    //依赖注入Mapper层接口
    @Autowired
    private studentmapper sm;

    //设置API，并且从Mapper层获取数据返回给前端
    @GetMapping("/selectstudent")
    public JsonResult SelectStudent(){
        List<Student> sdlist=sm.list();
        System.out.println(sdlist);
        return new JsonResult(sdlist);
    }

}

Mapper层：

package com.example.springboot_learn.mapper;

import com.example.springboot_learn.Pojo.Student;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

//Mapper注解将其放到Spring容器中
@Mapper
public interface studentmapper {

    //select注解进行查询数据，此外还有delete,insert,update都是一样的用法
    @Select("select * from mydb.student")
    List<Student> list();

}

 启动项目，根据API成功获取到从数据库查询到的数据