@OneToOne隨着@JoinColumn只保存在UUID，而不是整個對象

我使用Java + Spring + Hibernate的@OneToOne隨着@JoinColumn只保存在UUID，而不是整個對象

當測試下面的代碼，我得到一個錯誤：

javax.persistence.PersistenceException: org.hibernate.PropertyAccessException: could not get a field value by reflection getter of com.XXX.XXX.entity.Policy.id

@Entity 
@Table(name = "assignment") 
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS) 
public class Assignment extends BaseEntity { 

    @Id 
    @Column(name = "id") 
    @Type(type = "pg-uuid") 
    @NotTracked 
    private UUID id; 

    @OneToOne(targetEntity = Policy.class) 
    @JoinColumn(name = "policy_id", nullable = false, referencedColumnName = "policy_id") 
    @OnDelete(action = OnDeleteAction.CASCADE) 
    @TrackedEntity(isIdentityField = true) 
    private UUID policyID; 
} 

@Entity 
@Table(name = "policy") 
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE, region = "policy") 
@Inheritance(strategy = InheritanceType.JOINED) 
public class Policy extends BaseEntity { 

    @Id 
    @Column(name = "policy_id") 
    @Type(type = "pg-uuid") 
    @NotTracked 
    private UUID id; 

    ... 
    ... 
    .. 

}

當改變從UUID的private UUID policyID;到Policy，它的工作就好了，有沒有一種方法來設置莫名其妙內政策對特定對象的引用作爲ID，而不是等待策略的整個對象的分配對象裏面？

來源

2017-02-27 USer22999299

可能只包含UUID，但它不再是hibernate託管的FK。只要你想Hibernate來處理您的FK ..你會簡單地改變Assignment到我不建議這樣的：

@Entity 
@Table(name = "assignment") 
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS) 
public class Assignment extends BaseEntity { 

    @Id 
    @Column(name = "id") 
    @Type(type = "pg-uuid") 
    @NotTracked 
    private UUID id; 

    @Column(name="policy_id") 
    private UUID policyID; 
}

有了這樣說，你將失去所有級聯選項和FK檢查約束對這一領域的，除非你手動將它們添加到您的數據庫。

來源

2017-02-27 16:55:41 ninnemannk

我認爲沒有理由使用UUID而不是對策略對象的引用。你可以註釋你想延遲加載對象，所以它只是從數據庫加載，如果你想訪問另一個屬性的策略對象：

@OneToOne（targetEntity = Policy.class，fetch = FetchType .LAZY）

來源

2017-02-27 16:51:57 Markus

@OneToOne隨着@JoinColumn只保存在UUID，而不是整個對象

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