Event (UML)

An event (English Event ) is a model element in the Unified Modeling Language ( UML), a modeling language for software and other systems.

The behavior of a system is modeled with the UML, is always the behavior of cooperating instances of active classes. These instances are called active objects because they conceptually an "active life of its own " feature. In contrast, passive objects show no behavior, while from the outside arrives no motivation to do this. When an active object wants to influence behavior of other active or passive objects, hence a corresponding impetus is needed.

The UML2 calls such a " kick-off " event occurs (event occurrence, trigger) and not event. The Event understands the UML2, the nature or the type of event occurrence. This terminology is a bit confusing because they have not yet meet the Germans in English the normally assumed importance of event event respectively. In both languages ​​event usually referred to the specific occurrence, that is, that something is happening at any given time.

Types of events

  • Time event (Time Event ) stands for event appearances that arrive at a particular time. Time event can specify an absolute or relative time points.
  • Call event (call event ) stands for event appearances, which correspond to the invocation of an operation on an object.
  • Signal event (signal event ) stands for event appearances, the show receiving a signal at the receiving object.
  • Change event ( change event ) stands for event appearances, when changes in the course of the change of variables, the value of a Boolean expression from false to true.
  • UML language unit
311472
de