Up to this point, we have examined the features of transaction processing systems and how they can be used to create more robust applications. Microsoft Transaction Server is a transaction processing system that has been integrated with IIS and ASP to provide a complete application development platform for both Internet and intranet applications. Now what we have an understanding of what a transaction processing system can do, we need to look at how to create the components of the applications that will be part of the transactional application.
The components of the application will be straightforward COM components. They can be developed using any development tool that will create COM objects. These tools include Visual C++, Java, Delphi, and Visual Basic.
In a later section, we will cover the differences in the components created by these tools when we examine the differences in the threading model.
There are several areas that we will cover that make developing MTS-friendly components different from developing regular COM components. These areas include how to hold state in an object, issues surrounding the various threading models, and the scope at which objects are visible. In fact, every COM component can work in an MTS environment. It is just by adding a few bits of code that a COM component can become MTS-friendly, and thereby work much better.