【spring-boot】spring-boot使用JPAJ进行数据访问时，提示：org.hibernate.InstantiationException: No default constructor for entity: : com.springboot.jpa.entity.User

@Entity
@Table(name = "tb_users")
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)// 自增主键
    private Integer id;

    @Column(name = "name")
    private String name;
    @Column(name = "age")
    private Integer age;
    @Column(name = "sex")
    private String gender;
　　
　　//解决方案：

    public User() {
    }