org.hibernate.AnnotationException映射錯誤

Question

我正在試圖製作購物車的物品。用戶有多個項目，所以我這樣做： 我有一個@Entity @Table類項目，它實現Serializable

private User user; 

...

@Id 
@GeneratedValue(strategy = GenerationType.IDENTITY) 
public Long getId() { 
    return id; 
} 
public void setId(Long id) { 
    this.id = id; 
} 


@OneToMany(cascade = ALL, fetch = FetchType.EAGER, mappedBy = "items") 
@Column(nullable = true, updatable = false) 
public User getUser() { 
    return user; 
} 

和User.java（@Entity @Table實現Serializable）：

private List<Item> items; 
@Id 
@GeneratedValue(strategy = GenerationType.IDENTITY) 
public Long getId() { 
    return id; 
} 

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

...

@ManyToOne 
public List<Item> getItems() { 
    return items; 
} 

public void setItems(List<Item> items) { 
    this.items = items; 
} 

我得到的是這樣的錯誤：

Caused by: org.hibernate.AnnotationException: Illegal attempt to map a non collection as a @OneToMany, @ManyToMany or @CollectionOfElements: org.auction.model.Item.user"}} 

Answer 1

你有你的註釋混在一起，@OneToMany是收集

的一組中的項目類

@ManyToOne(cascade = ALL, fetch = FetchType.EAGER) 
@Column(nullable = true, updatable = false) 
    public User getUser() { 
    return user; 
    } 

，並在用戶你將有OneToMany

@OneToMany(mappedBy = "user") 
public List<Item> getItems() { 
    return items; 
}