COM IDL and Interface Design

An expert-mode guide to the inner workings of the Distributed Component Object Model (DCOM), COM IDL and Interface Design also provides some excellent sample code for objects that are useful for an e-commerce Web site. The author argues that you can design with Interactive Data Language (IDL) manually and then write the code behind it in C++, Visual Basic, or Java.

The book begins with a quick tour of Component Object Model (COM) basics, including interface diagrams and dual interfaces (used for scripting COM objects in VB). Next comes material on remote method calls and DCOM, including some excellent material on apartment models and marshalling. There is a thorough guide to all IDL data types, whether basic types, arrays, references, and pointers or VB automation data types (such as BSTRs and Variants). A chapter on application design displays the author's considerable knowledge of COM and software patterns.

The heart of this book is the author's case study of COM objects needed for an electronic auction Web site. After walking through the design process, the author creates all the relevant COM objects in IDL. Next he shows client-side test programs written in Visual Basic, Visual J++, Visual C++ (and Microsoft Foundation Class [MFC]), VBScript, and JavaScript. The last part of the book builds the server-side objects (based on his IDL) in C++ using the leading-edge ActiveX Template Library (ATL) for fast performance. The author gives you everything you need here including several custom extensions to ATL.

Filled with expert knowledge, COM IDL and Interface Design turns out to be one of the best available guides for advanced development with distributed objects in DCOM on the Microsoft platform. --Richard Dragan