Have read somewhere on the net, but couldn't google it again, that static
classes are for utility methods and should not be used for executing
business operations. Using static methods makes the code procedural and is
not object oriented.

Technically, static DAO methods would work though.

Jayaraman




              Marvin Toll
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              12/18/2004 02:14 PM
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Having recently participated on my first production implementation using
O/R Persistence (Toplink) - the team had an interesting design for DAOs.

A base abstract DAO class contained convenience methods and sub-classed
DAOs contained only static methods (with a private constructor). No DAO
Factory was required. Unit testing was conducted on the Application
Service objects - enabling Mock substitution of Business Objects as
needed. Both connection and transaction management were handled within
the Application Service objects and these resources were passed to the
DAOs as arguments.

What is interesting - is that the design decision for using static methods
was to promote/reinforce consistent use of stateless DAOs. In addition,
because the sub-classed DAOs were not instances - in effect, the Base DAO
static methods could be "overridden" by the sub-classed DAOs.

This is a different assertion for using static methods in DAOs then I've
previously encountered - and it worked very effectively for the team.

Any reaction to the notion of using static methods as a
convention/strategy for keeping state out of DAOs???

_Marvin

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