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Newsgroups: comp.lang.java.programmer
Date: Mon, 16 Nov 2015 14:42:28 -0800 (PST)
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Subject: Re: What to tell in a talk about JPA
From: Lew <lewbloch@gmail.com>
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On Friday, November 13, 2015 at 2:47:03 AM UTC-8, Cecil Westerhof wrote:
> I am in the middle of migrating a series of applications. One thing is
> that JDBC has to be replaced with JPA. I am going to give a
> presentation about this on T-DOSE. (The biggest Open Source event in
> the Netherlands.) This was/is my first time that I work with JPA. So I
> am far from being an expert. What are things that are useful to
> mention? The talk is three quarters of an hour and beside JPA I will
> also talk about the pitfalls we experienced during the migration.

The main thing is that JPA is NOT A DATA-MANIPULATION TECHNIQUE. It is an object-manipulation technique. The single biggest mistake is to use JPA as a wrapper for SQL rather than a persistence mechanism for objects.

The second mistake is to keep a 'DataManager' around too long. They should be ephemeral.

-- 
Lew