Nested embeddable - AttributeOverride for embeddable within embeddable

问题

I have class Money which is an @Embeddable

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

When I useit multiple time inside entity, everything works fine. For example

@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;
}

Code above works perfectly.

Now the problem occurs when I have another @Embeddable that I want to have Money instances in it and that @Embeddable is used by an entity multiple times. Example:

Embeddable

@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;

Entity

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

    @Id
    private Long id;

    @Embedded       
    private ReportCostValues contracted;

    @Embedded       
    private ReportCostValues current;

    @Embedded        
    private ReportCostValues previousReport;

This code above will not work. Any ideas how to approach this problem?

回答1:

Hi you have to use @AttributeOverrides judicially,you have to override attributes once again in entity that you have done in embeddable ReportCostValues class, hope code below is what you are looking for.

@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;




}

Hope this helps !!!!!

来源：https://stackoverflow.com/questions/9845575/nested-embeddable-attributeoverride-for-embeddable-within-embeddable

标签

hibernate

jpa

embeddable