springboot入门案例

/**描述：学生实体类
 * @author boyas
 * @create 2021/8/28 17:21
 */
public class Student {
    Integer id;
    String name;

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}';
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

/**描述：学生Controller
* @author boyas
 * @create 2021/8/28 17:06
 */
@RestController
public class StudentController {
    @Autowired
    StudentService studentService;
    @GetMapping("/student")
    public String student(@RequestParam Integer num){
        final Student student = studentService.findStudent(num);
        return student.toString();
    }
}

/**
 * @author boyas
 * @create 2021/8/28 17:11
 */
@Mapper
@Repository
public interface StudentMapper {
    @Select("select * from student where id = #{id}")
    Student findById(Integer id);
}

/**
 * @author boyas
 * @create 2021/8/28 17:09
 */
@Service
public class StudentService {
    @Autowired
    StudentMapper studentMapper;
    public Student findStudent(Integer id){
        return studentMapper.findById(id);
    }
}

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.url=jdbc:mysql://localhost:3306/springbootlearn?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true

CREATE TABLE `student`  (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic;
INSERT INTO `student` VALUES (1, '小明');
INSERT INTO `student` VALUES (2, '小慕');