Design Patterns discussion

[Andrew Chelyabin <chelyabin AT sctest.vrn.ru>]

On Tue, 2003-06-10 at 19:25, Hainer, Neil wrote:

> I know I will have to do the same thing for another vendor's document
> extraction product. That product will have its own unique results
> object and have unique method names.
> 
> So....
> 
> How can I design my code so I can re-use the RDF code with different
> vendor's results objects?

You can use "Template Method" GOF pattern. Your AbstractClass
(RDF_writer) will implement TemplateMethod (write_to_file) and declare
some primitive (data extraction) operations. Each ConcreteClass
(Result1_RDF_writer, Result2_RDF_writer) will override data extraction
methods to obtain desired information from concrete data source object
(Result1, Result2).

So you will have the algorithm of formatting incapsulated to RDF_writer
and concrete ResultX_RDF_writers which will know all about specific
ResultX interface.

-- 
Andrew Chelyabin 
<chelyabin AT tspotest.comch.ru>