by
Geoff McIlraith >> Tue, 8 Jun 1999 0:04:38 GMT
Does that mean external applications written in languages like VB, C++, or Delphi can now access a Jade Database through COM objects?
You will have access to JADE objects through COM objects.
Will each object have its own COM interface or will the interface be at a lower level?
Each object will have its own ActiveX interface. The interface will be the COM equivalent of the JADE methods and properties you chose to expose (the implementation then converts the parameters to JADE data types, and calls sendMessage, but you'd never know).
More details:
JADE 5 will support the exposure of JADE objects through the generation of an ActiveX server DLL. The generation process is very straight-forward with wizards being employed to do the work for you - You don't have to write any code.
Once the ActiveX server has been generated, it can be added to the list of references in VB, (or the equivalent for C++ and Delphi) and the classes become available for interaction in this environment.
A couple of technical notes:
The DLL may be statically bound, which gives if better performance than dynamic binding. This does mean that when changes are made to the definitions of the exposed JADE classes, the DLL needs to be re-generated (because the interface will have changed). For this reason, it is best to have your JADE class interfaces stable before exposing through ActiveX.
The generation of the DLL requires the use of Microsoft's Visual C++ version 6, so this needs to be available to the developer wanting to expose ActiveX interfaces (not required in order to use the DLL though).
Hope this helps,
Geoff