Common Mechanisms of UML

Common Modeling Techniques 

• Modeling a Family of Signals 
• Modeling Exception

Modeling a Family of Signals 

To model a family of signals:

• Take into account all the different kinds of signals, to which a given set of active objects may respond 
• Identify the common types of signals and put them in a generalization/specialization hierarchy using inheritance 
• Put the general ones on the top of the hierarchy and the specialized ones at the bottom

Modeling Exception 

To model exceptions: 

• Identify the exceptional conditions that may be raised for each operation in each class and interface, and model them as signals 
• Place these exceptions in a hierarchy 
• Raise the general ones and lower the specialized ones. Also, introduce intermediate exceptions, wherever necessary 
• Model these signals as send dependencies from the operation to its exceptions