Re: [Firebird-devel] Providers, yvalve, external engines and object lifecycle

[Kovalenko D. <dmi...@gm...>]

Hi people

I can't read all your messages in this debate

But I can say next simple things (forgive me my bad english)

1. At current time, you (FB Developers) do not has any real expirience with 
object-based interfaces. I right? :)

2. Object-based interfaces should use the refcount. Without this thing, you 
get the multiple problems. And clients of these interfaces, also.

3. Try think about replace of your Version to normal QueryInterface. If you 
do not understand now, you understand in future. Five years ago, you did not 
understand the meaning of benefits of refcount :)

I wrote to Alex about the real problems with current "Version" method.

4. Last release of transaction-object with active (but not prepared) 
transaction should make the rollback this transaction. Without any errors.

Last release of connection with active connection should make the detach 
from database. Without any errors.

5. Addref/Release should be thread-safe (use Interlocked functions).

In common case - all methods of all interfaces should be thread-safe.

6. Interface method should return the new object through OUT-parameter like 
(T** ppObject). In ideal - you should return the pointer to BASE-interface.

Do not return (T*) from interface method. This is way for create the 
mistakes in client code.

7. Do not work with interfaces directly. Use the smart pointers with correct 
implementation :-)

Regards,
Kovalenko Dmitry
www.ibprovider.com

PS. Use doxygen for documentation of your interfaces and prefix "IFB_" for 
interface names :))))