Interesting question (again) is how one handles the persistence of dependent
objects. I quess there are at least two options:
1. Make dependents as regular Java classes (e.g. Address). Then Person may
be a entity bean with Adress attribute(s) or references. Using RDBMS you can
persist this Java class in one blob (which seems to be to usual solution
with CMP though Some CMP solutions may provide some custom mappers) or you
can use BMP and write the required code to persist the class in appropriate
table/columns. Blobs makes it difficult to figure out what's stored in your
database if you are using some query tools.
2. Use the entity beans for Address too. For many cases this seems a pretty
heavy-weight solution.
You also have to decide what to do when the Person instance is deleted.
Usually you want to delete the dependent objects too.
Regards,
Jouni
> -----Original Message-----
> From: A mailing list for Enterprise JavaBeans development
> [mailto:[EMAIL PROTECTED]]On Behalf Of Richard Monson-Haefel
> Sent: Tuesday, February 22, 2000 11:16 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Dependent classes
>
>
> That last post was difficult to read, so here it is again with
> the line breaks
> fixed:
>
> "Dependent objects are objects that only have meaning within the
> context of
> another business object. They typically represent fairly
> fine-grained business
> con-cepts, like an address, phone number, or order item. For example, an
> address has little meaning when it is not associated with a
> business object
> like Person or Organization. It depends on the context of the
> business object
> to give it mean-ing. Such an object can be thought of as a
> wrapper for related
> data. The fields that make up an address (street, city, state,
> and zip) should
> be packaged together in a single object called Address. In turn,
> the Address
> object is usually an attribute or property of another business
> object; in EJB,
> we would typically see an Address or some other dependent object
> as a property
> of an entity bean."
>
> -- Richard
> --
> Author of Enterprise JavaBeans
> Published by O'Reilly & Associates
>
> EJB FAQ
> http://www.jguru.com/faq/EJB
>
> EJBNow.com
> http://www.ejbnow.com
>
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