Re: Apache JDBC utils

From:
Lew <lewbloch@gmail.com>
Newsgroups:
comp.lang.java.programmer
Date:
Wed, 2 May 2012 11:16:53 -0700 (PDT)
Message-ID:
<17910424.2120.1335982613195.JavaMail.geo-discussion-forums@pbcoq1>
On Tuesday, May 1, 2012 8:57:28 AM UTC-7, markspace wrote:

On 5/1/2012 6:29 AM, Arved Sandstrom wrote:
 

On 12-04-30 11:27 PM, markspace wrote:

If the authors of the projects say it's not ORM, I'll choose to believ=

e

them.

 

To an extent I'm happy to go with what authors say also. More precisely
DBUtils *is* an ORM - just look at the available ResultSetHandler

 
 
Right-o. I knew what Lew meant, but I still found his statement to be
inaccurate. It was clearly an exaggeration to say that dbutils is an
ORM just like JPA or Hibernate. JPA and dbutils are practically on


I didn't say "just like JPA or Hibernate".

Nor did the OP.

different planets. They solve a similar problem, but they take very
different approaches.
 
 

I prefer to differentiate between basic OR mappers like DBUtils that do

 
 
This is good, I like the term "mapper" here instead of ORM. Data Mapper=

 

is a design pattern. Specifically it's a lighter-weight one that DAO,
so it's a good fit to what dbutils is trying to accomplish.


The "M" in "ORM" stands for "mapping" or "mapper".

<http://martinfowler.com/eaaCatalog/dataMapper.html>
<http://rrees.wordpress.com/2009/07/11/the-dao-anti-patterns/>


By "monolithic" I mean, in the case of JPA, creating one data-access layer =
which sits between all object code and all DB access. Using a single 'Entit=
yManager' to handle many things for a long time is monolithic, and causes p=
ersistence sessions to fill and get slow. Funneling everything through a si=
ngle data-access construct suffers from the "God object" complex.

"Non-monolithic" means, for example, a separate data-access class for each =
module that needs access. So your "FooOrder" module will have a data-access=
 object with its own 'EntityManager', "BazHistoryMarker" will have another,=
 and so on.

This makes data access easier to reason about and to troubleshoot. It also =
obviates various run-time problems.

As for "lightweight", I have only heard, "not many API calls" as a metric. =
How does dbutil rate as lighter than JPA by that metric? Even the short sni=
ppet posted here of dbutil code looks messier and harder to set up than JPA=
..

JPA is the first ORM (sorry, folks, dbutil is an ORM) I've found worth usin=
g. I avoid Hibernate's JPA because it's too easy to slip into pre-JPA idiom=
s with it, which in my view ruin its utility when you do.

JPA has shown itself the leanest (in terms of programmer effort) and slicke=
st way to handle its intended use cases (e.g., not bulk inserts) of anythin=
g I've tried.

Unless it's abused horribly, which I've also seen. But the abusers of JPA a=
re no better with JDBC, other Java idioms, and I predict nor with dbutils.

--
Lew

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