Designing components versus objects: a transformational approach

A good object oriented design does not necessarily make a good component based design, and vice versa. What design principles do components introduce? The paper examines component based programming and how it expands the design space in the context of an event based component architecture. We present a conceptual model for addressing new design issues these components afford, and we identify fundamental design decisions in this model that are not a concern in conventional object oriented design. We use JavaBeans based examples to illustrate concretely how expertise in component based design, as embodied in a component taxonomy and implementation space, impacts both design and the process of design. The results are not exclusive to JavaBeans; they can apply to any comparable component architecture.