Backward compatibility with interfaces

Hi,

In our Java products we have a plugin based system using JPF [1].  When we
develop some enhancement for any interface we don't break the earlier
plugins which are relying on that interface, instead we create one more
interface say XyzPlus extends Xyz.  The main code still needs change and it
now checks whether the plugin is implementing Xyz Interface or XyzPlus and
accordingly it calls the methods.

I believe this is a standard procedure used in products which are being
updated periodically with new features.  I am wondering whether this type of
usage is recognized as any pattern in the industry.  Do we have any name for
this type of usage to keep the backward compatibility?


with regards
Tushar

[1] http://jpf.sourceforge.net/

==============================================
Tushar Joshi, Nagpur
MCSD_NET C#, SCJP, RHCE
Software Engineer and Senior Project Manager @ Infospectrum India Private
Limited, VOC Captain for NetBeans, JUGNagpur Leader
http://www.info-spectrum.com
http://www.tusharvjoshi.com
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