You have used most of the tools of object design already:
- Object model: For many people this phrase is synonymous with class diagram. However, the model in a larger sense also includes the object diagram and package diagram.
- Interaction diagram: A generic term referring to the two UML diagrams that model object interaction (communication), namely the sequence and collaboration diagrams.
- Activity diagram: The UML version of a flowchart with added features to model concurrent activities.
You will continue to use these same tools in object design. But now you will add different details to the diagrams. In addition, you will use the
statechart (also called the state transition diagram) to model object life cycles and state-specific behaviors.
Review the relationships between the different diagrams in the MouseOver below.
In order to benefit from the diagrams, you need to understand the relationships between the diagrams.
- Present concise descriptions of what you know and decide about the system
- Represent different views of the system
Together, however, the various diagrams represent a complete picture of how the system is structured and how the objects work.
By comparing the different views, you can identify inconsistencies and improve the overall model.
Many CASE tools now provide consistency reports to compare the diagrams and highlight inconsistencies in the uses of specific model elements, such as events and objects. Others provide a scripting language that allows you to define your own reports.