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Adds new methos to BDMain

Pablo Manrubia

Joined: Dec 29, 2007
Posts: 6
Hi all!,

My app is a 3-tier application.

Id' like to change DBMain interface (addings 3 methods)
1) public void setLockStrategy(LockStrategy)
2) public Accommodation recordToAccomodation(String[] record)
3) public String[] accomodationToRecord(Accomodation ac)

1) Just to be able to disable/enable lockstrategy in DAO (DBMain). I don't like using singleton with a LockManager
2) and 3): Application of value object pattern in DAO. In my opinion DBMain is responsible to transform domain objects (bussiness objects) in database format objects

Thanks in advance
Pablo Manrubia

Joined: Dec 29, 2007
Posts: 6
Sorry but I forgot the question...

Am i authorized to do this change according to SUN exam rules??

Nicolas Stern
Ranch Hand

Joined: Apr 26, 2002
Posts: 57
Hi pablo,

I think adding methods to the interface is penalized by automatic failure.

My assignment states :

Your data access class must be called "", must be in a package called "suncertify.db", and must implement the following interface:

Which does not mean you can't add methods to your Data class. But I think the interface DBMain must be used as is.

HTH - Cheers - Nicolas
[ January 07, 2008: Message edited by: Nicolas Stern ]
Alex Belisle Turcot
Ranch Hand

Joined: Apr 26, 2005
Posts: 516

2 things:

- adding private methods;
- adding public methods.

private methods are OK, no questions asked.

For public methods, it's not that it's forbidden, however if you Data depends on those methods, it cannot be used from its Interface.

It would be bad, and on top of that, if SUN has some test on your Data implementation, they will certainly access it through the interface!

Also, my Data Singleton returns the a reference to the Interface.

Pablo Manrubia

Joined: Dec 29, 2007
Posts: 6

I won't add new methods to DBMain interface.

Thanks both for your replys.
I agree. Here's the link:
subject: Adds new methos to BDMain
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