External Data providersin Calc - GSoC project

Hi all,

I looked into how to make UNO components for calc and referred to
Solver.idl and XSolver.idl in  offapi module for more understanding.

I am thinking of moving the existing implementation of dataproviders and
datatransformations (located at sc/source/ui/dataproviders) to two UNO
components.

This would mean creating 4 new files in offapi/com/sun/star/sheet namely

ExternalDataProvider.idl
XExternalDataProvider.idl
DataTransformations.idl
XDataTransformations.idl

ExternalDataProvider will host the following methods:
1. void Import()
2. OUString& GetURL()
3. map<OUString, OUString> getDataSourcesForURL(const OUString& rURL)
4. unique_ptr<SvStream> FetchStreamFromURL(const OUString&, OStringBuffer&
rBuffer)


DataTransformation will host all the methods defined in
datatransformation.hxx

I want to convert the existing implementations to UNO so that external
application developers can make use of the functionality as well.

Looking for suggestions and feedback.

Kind Regards,
Vikas Mahato