Activity diagram

The activity diagram ( activity diagram engl. ) is one of the fourteen types of diagrams in the Unified Modeling Language ( UML), a modeling language for software and other systems.

Generally

The activity diagram is a behavior chart. It shows a particular view of the dynamic aspects of the modeled system. An activity diagram represents the networking of elementary actions and their connections with control and data flows graphical form with an activity diagram the flow of a use case is usually described, but it is suitable for the modeling of all activities within a system.

In UML2, the semantics of activity diagrams has moved very close to Petri nets and allows better now the representation of concurrent systems through the integration of asynchronous communication mechanisms (sending and receiving signal, exception handling ). An activity diagram specifies an activity. The detailed rules for how tokens flow in an activity form the basis for the interpretation of an activity diagram.

The activity diagram is an object-oriented adaptation of the program flow chart (PAP, often referred to as a program flow chart ).

UML 2 activity diagram

The right picture shows an example of a simple activity diagram with a header and a content area. The keyword in the header is act or activity in an activity diagram. Lie on the boundary as rectangles, two activity parameter nodes. On two of the actions ( here rectangles with rounded corners) are the input and the output pin (small squares located on the edge ) to see which are connected by an object flow. The other arrows represent control flows dar. The black circle is the starting node ( one of the control nodes).

The crucial difference between the seen in the lower graph and standing for particular control node hash marks and bar symbols is the following: for the diamonds, the token number for the bar and maintaining the token number modification applies.

1 UML activity diagram

Activity diagrams in UML 1.x look similar to activity diagrams in UML 2, the importance of individual graphic symbols but has substantially changed in the new language version. Rounded rectangles are in activity diagrams of UML 1.x, for example, for states, while so actions are symbolized in activity diagrams of UML 2. The horizontal thick lines are called parallelization and synchronization nodes ( or beams ) and can dig up or merge transitions. By diamond, a branch of a transition is also shown. The conditions are enclosed in square brackets at the respective branch.

Credentials

  • Christoph Kecher: UML 2.0 - The Definitive Guide. Galileo Computing, 2006, ISBN 3-89842-738-2
  • Heath Balzert: Textbook of object modeling - analysis and design with UML, 2nd Elsevier Oxford University Press, 2005, ISBN 3-8274-1162-9
Class diagram Component diagram Composite structure diagram Object diagram Profile diagram Deployment diagram Timing diagram (Unified Modeling Language) Action (UML)
28053
de