Nested embeddable - 可嵌入的 AttributeOverride答案

【问题标题】：Nested embeddable - AttributeOverride for embeddable within embeddableNested embeddable - 可嵌入的 AttributeOverride
【发布时间】：2012-03-23 19:44:27
【问题描述】：

我有一个 @Embeddable 类的 Money

@Embeddable
public class Money implements Serializable, Comparable<Money> {
    @Column(name = "amount", precision = 15, scale = 2)
    private BigDecimal amount;
}

当我在实体内多次使用它时，一切正常。例如

@Entity
public class SomeEntity implements Serializable {

    @Embedded
    @AttributeOverride(name = "amount", column = @Column(name = "entry"))
    private Money entryValue;

    @Embedded
    @AttributeOverride(name = "amount", column = @Column(name = "leave"))
    private Money leaveValue;
}

上面的代码完美运行。

现在，当我有另一个 @Embeddable 我想在其中包含 Money 实例并且 @Embeddable 被实体多次使用时，就会出现问题。示例：

可嵌入

@Embeddable
public class ReportCostValues implements Serializable {

    @Embedded
    @AttributeOverride(name = "amount", column = @Column(name = "covered_by_grant"))
    private Money coveredByGrant;

    @Embedded
    @AttributeOverride(name = "amount", column = @Column(name = "own_resources"))
    private Money foundedFromOwnResources;

    @Embedded
    @AttributeOverride(name = "amount", column = @Column(name = "personal_contribution"))
    private Money personalContribution;

实体

 @Entity
 public class ReportCostEntity implements Identifiable<Long>, Serializable {

    @Id
    private Long id;

    @Embedded       
    private ReportCostValues contracted;

    @Embedded       
    private ReportCostValues current;

    @Embedded        
    private ReportCostValues previousReport;

上面的这段代码不起作用。任何想法如何解决这个问题？

【问题讨论】：

标签： hibernate jpa embeddable

【解决方案1】：

您好，您必须在司法上使用@AttributeOverrides，您必须在可嵌入ReportCostValues 类中完成的实体中再次覆盖属性，希望下面的代码是您正在寻找的。p>

@Entity 
public class ReportCostEntity implements  Serializable {

    @Id
    private Long id;

    @Embedded   
    @AttributeOverrides( {
        @AttributeOverride(name="coveredByGrant.amount", column = @Column(name="contracted_coveredByGrant") ),
        @AttributeOverride(name="foundedFromOwnResources.amount", column = @Column(name="contracted_foundedFromOwnResources")),
        @AttributeOverride(name="personalContribution.amount", column = @Column(name="contracted_personalContribution"))
    } )
    private ReportCostValues contracted;

    @Embedded
    @AttributeOverrides( {
        @AttributeOverride(name="coveredByGrant.amount", column = @Column(name="current_coveredByGrant") ),
        @AttributeOverride(name="foundedFromOwnResources.amount", column = @Column(name="current_foundedFromOwnResources")),
        @AttributeOverride(name="personalContribution.amount", column = @Column(name="current_personalContribution"))
    } )
    private ReportCostValues current;

    @Embedded 
    @AttributeOverrides( {
        @AttributeOverride(name="coveredByGrant.amount", column = @Column(name="previousReport_coveredByGrant") ),
        @AttributeOverride(name="foundedFromOwnResources.amount", column = @Column(name="previousReport_foundedFromOwnResources")),
        @AttributeOverride(name="personalContribution.amount", column = @Column(name="previousReport_personalContribution"))
    } )
    private ReportCostValues previousReport;




}

希望对你有帮助！！！！！！

【讨论】：