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Create Hibernate @ManyToOne a Scala Association Option Type

Does anyone have an example of using a wrapper object like Scala Option for @ManyToOne associations in Hibernate?

Thank.

Edited: Thanks for the suggestions. After I thought, I decided to use private variables and expose them to Scala getters / setters, which return Option [MyType]. Like this:

class EmailFolder(__parent: Option[EmailFolder] = None) {

    //.... default constructor etc...

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "parent_id")
    private[this] var _parent: EmailFolder = __parent.orNull
    def parent = Option(_parent)
    def parent_=(newVal:Option[EmailFolder]) = _parent = newVal.orNull
}

This works, and I no longer need to work with zeros in my application.

- Andreas

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, , , :

  • "... ..." @ManyToOne Hibernate. Hibernate Entity Entity: .. DomainObject, Hibernate , .
  • "... null values ​​..." Hibernate Elements (aka @Embeddable). , , null.

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...
@ManyToOne
private MyObjectType myObjectReference;

public Option<MyObjectType> getMyObject() {
    return new Option(this.myObjectReference);
}
...

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, .

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