29-06-2012, 12:14 PM
UML Diagrams
UML.ppt (Size: 191 KB / Downloads: 90)
Use Cases (Anwendungsfall)
Used to describe the main processes in a system and the interactions between the processes (use cases) and external systems or individuals called actors.
Once the overview is developed it can be expanded to include subprocesses.
The use case description is a generic scenario that is a series of sentences describing each step in the interaction between an actor and a use case.
Modeling of the system
To model classes:
Identify their responsabilities
Verify the balance between responsabilities (divide the classes with too many responsabilities & eliminate those with very few trivial responsabilities)
Find the attributes and necesssary operations (methods) to accomplish those responsabilities.
HW elements that contain SW : nodes
Aggregation
Aggregation is a special type of association: a part-whole relationship - a class has an attribute which is an object of another class.
Composition is a special case of aggregation where
The class is the only one that has objects of that class as attributes
This class is the only one that can create or destroy these objects.
Object Diagrams
Objects are also represented in rectangles, their names underlined & written with first letter in small case.
Names of objects can be written in 4 ways: