我有一个类的Question和一个类的Response:
@Entity
public class Question implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
protected Long id;
protected String texte;
@OneToMany(mappedBy="question")
private List<Reponse> reponses;
@Entity
public class Reponse implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
protected Long id;
@ManyToOne
@JoinColumn(name = "question_id")
private Question question;
[当我从数据库中调用类型问题时,这还应该带给我一个由“问题”映射的响应列表。
但是我得到了一个NULL值,并且该堆栈在List对象中:
错误=发生异常:com.sun.jdi.InvocationException
有人知道这会是什么吗?
您需要热切地获取响应:
@OneToMany(mappedBy="question", fetch = FetchType.EAGER)
private List<Reponse> reponses;