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Struts & Hibernate
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| | | How to realize extendable data objects? | How to realize extendable data objects? 2003-09-23 - By PavanKumar Keely
Back
If my understanding is correct,
Existing scenario: If new module is installed then
Material has to be changed according to the new module
( adding attributes etc )
Many modules in the application will use this Material
object. Making this Material Object an instance of
Hashtable/HashMap can solve your problem. Because you
can just add one more attribute to this as simple as
that and use that attribute in the new module. But one
problem with this approach is we need to stick to the
standard key names throughout the application. But
avoid hardcoding the key name and use some
initialization file, which will be initiated at the
start of the server. This solution is on the lines of
EJB Design pattern "DTO using HashMap".
One more way of achieving extendibility is using XML
data object. Whenever you create Material object that
should form the data in the XML. But one problem with
this approach is building XML and parsing the XML.
if you have any queries or if you get a better
solution than this please do let me know.
thanks and best regards,
Keely Pavan
TATA Consultancy Services, Bangalore
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