Summary

In this chapter, I described the CAD/CAM problem.

• I must extract information from different CAD/CAM systems in the same way. This will allow a system in which the company has a great investment (an expert system) to continue working without expensive modifications every time the CAD/CAM systems changes.

• I have two systems that are implemented in completely different ways, even though they contain essentially the same information.

This task has many similarities to other problems I have run across in projects. There are different specific implementations of systems, but I want to allow other objects to communicate with these different implementations in the same way.