server:
  port: 8081
spring:
  #數(shù)據(jù)庫(kù)連接配置
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/dt55?characterEncoding=utf-8&useSSL=false&serverTimezone=UTC
    username: root
    password: 888888
#mybatis的相關(guān)配置
mybatis:
  #mapper配置文件
  mapper-locations: classpath:mapper/*.xml

public class Student {
    private int id;
    private String name;
    private int age;
    private String hobby;
    private String address;
    public Student(int id, String name, int age, String hobby, String address) {
        this.id = id;
        this.name = name;
        this.age = age;
        this.hobby = hobby;
        this.address = address;
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getHobby() {
        return hobby;
    }
    public void setHobby(String hobby) {
        this.hobby = hobby;
    }
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }
}

@Mapper
public interface StudentMapper {
    List<Student> findAllStudent();
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.wzy.demo.mapper.StudentMapper">
    <select id="findAllStudent" resultType="com.wzy.demo.entity.Student">
        SELECT * FROM student
    </select>
</mapper>

//@Service的意思是將其實(shí)例化,
//之前如果有一個(gè)class，是不是需要new一個(gè)對(duì)象才可以用，
//這里就可以理解成會(huì)自動(dòng)幫你new，new完了之后，將實(shí)例加到了spring容器當(dāng)中
@Service
public class StudentService {
    //引進(jìn)StudentMapper,@Autowired的意思就是將其實(shí)例化，通過(guò)autowired從spring容器中拿出來(lái)，供我們使用
    @Autowired
    private StudentMapper studentMapper;
    //處理業(yè)務(wù)邏輯，這里由于業(yè)務(wù)過(guò)于簡(jiǎn)單，就空著，查詢(xún)出什么我就返回什么
    public List<Student> findAllStudent() {
        return studentMapper.findAllStudent();
    }
}

//@RestController會(huì)自動(dòng)幫一個(gè)對(duì)象轉(zhuǎn)換成json的格式
@RestController
public class StudentController {
    @Autowired
    private StudentService studentService;
    //@RequestMapping("/getstudent")的意思告訴前端相應(yīng)的地址訪(fǎng)問(wèn)
    @RequestMapping("/getstudent")
    public List<Student> getStudent(){
        return studentService.findAllStudent();
    }
}