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when to throw DuplicateKeyException

fei lin
Ranch Hand

Joined: Nov 25, 2007
Posts: 39
in my create() of the interface, it throws DuplicateKeyException.
When should this be throw?
Vinicius Florentino

Joined: Feb 26, 2008
Posts: 16
Depends. In my code: never.
Gilles Marceau
Ranch Hand

Joined: Feb 17, 2007
Posts: 78
It depends the meaning you give to the record key.

One option is to consider the record key to be the record number. The
DuplicateKeyException is never thrown in that case (record numbers are all

Another option is to consider a subset of the record data as the key. For
example, contractor name + contractor location. But in that case, the update
method should throw the same exception.

This is really a matter of design choice.

[ March 05, 2008: Message edited by: Gilles Marceau ]

SCJP 1.5<br />SCJD 1.6<br />SCBCD in progress...
I agree. Here's the link:
subject: when to throw DuplicateKeyException
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