different roles (Cohen, 1998). An example flowchart is seen on Figure 3. Our goal has user role requirement also described in the requirements and this approach is highly usable for our example as well.
2.3. Object modelling languages, UML & UML2 Unified Modelling Language (UML) is one of the most known languages for displaying and drawing different software diagrams. UML is the international standard notation for object-oriented analysis and design. It is defined by the Object Management Group7 (Graham & Wills, 2007). UML2 uses 13 types of different diagrams, which are categorized as follows: Structure diagrams: •
Class diagram
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Component diagram
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Composite structure diagram
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Deployment diagram
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Object diagram
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Package diagram
Behavior diagrams: •
Activity diagram
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State Machine diagram
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Use case diagram
Interaction diagrams: •
Communication diagram
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Interaction overview diagram
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Sequence diagram
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Timing diagram
As it can be seen, this listing of diagram types is quite massive if compared with other visual modelling languages. Clearly most of the listed types are not suitable for our purposes and cannot be adopted for different reasons. For example class diagram is
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