-----Original Message-----Can somebody tell me whether there is a standard for O/R mapping with EJB 2.0 CMP ? Or is the O/R mapping stuff a part of EJB 2.0 specs ? Here are two pieces of information from two EJB 2.0 books.
From: A mailing list for Enterprise JavaBeans development [mailto:[EMAIL PROTECTED]]On Behalf Of Da-Ming Duan
Sent: Tuesday, August 14, 2001 1:48 PM
To: [EMAIL PROTECTED]
Subject: Any Standard for O/R Mapping with EJB 2.0 CMP ?In chapter Overview of "The Manual of EJB 2.0 Persistence" (MVCSoft Persistence Manager):
"The new EJB 2.0 persistence model is not just a fine-tuning of features that were available in the EJB1.1 specification. Instead, EJB 2.0 persistence is a revolutionary addition of a standards-based object-relational mapping framework to Enterprise JavaBeans technology... But there has never before been a standard for object-relational mapping.
There are many advantages to standards-based development. First... Second... Third, because many vendors are implementing the same standard, the technology is likely to succeed and grow."
What are the standards?
In chapter Persistence Best-Practices of "Mastering EJB II" (http://www.theserverside.com/resources/ejb_review.jsp)(section Choosing between CMP and BMP):
"Unfortunately, there is no standard way to specify the actual O/R mapping with CMP. Each container has their own tools, wizards, and/or mapping files that specify which fields correspond to which database columns. But what if you want to install your bean in a different container? You'll now need to re-specify your persistent operations using the new container's tools."
It seems there is not a standard.
Da-Ming
EJB
2.0 Spec defines a standard way to "specify" a mapping between two Entity
Beans. EJB 2.0 Spec does not define a way to "implement" such a
mapping. Each container adheres to the specification in it's own
way.
-AP_
- Any Standard for O/R Mapping with EJB 2.0 CMP ? Da-Ming Duan
- Alex Paransky
