In UML modeling, a trigger is an event that initiates a transition from one state to another. A guard condition is a boolean condition that must be satisfied for a transition to occur. An effect is the action or activity that happens when a transition occurs.
Adding call triggers to transitions
In UML modeling, a call trigger is an event that represents the receipt of a request to invoke an operation. A transition with a call trigger initiates when the called operation is invoked.Adding change triggers to transitions
In UML modeling, a change trigger is an event that represents a condition. The condition is defined by a boolean-valued expression that triggers a transition when its value changes from false to true.Adding signal triggers to transitions
In UML modeling, a signal trigger represents a specific message that initiates a transition when an object receives it.Adding time triggers to transitions
In UML modeling, a time trigger is an event that represents the passage of a defined period of time or an absolute time. A transition with a time trigger initiates when the time value is satisfied.
Parent topic: Creating transitions between states
Related concepts
States, regions, and transitions