State Diagram

What is State Diagram?  State diagram is used to show the state space of a given class, the events that cause a transition from one state to another, and the action that result from a state change.

Elements of State Diagram  State The state object is a snapshot of an object at a particular point in its life. A state may have an activity describing the function being performed.  Symbol:

Elements of State Diagram  Transition Transition indicates a movement from one state to another.  Event It is a noteworthy occurrence that triggers a state transition. If you use multiple transitions with the same event, the guards must be mutually exclusive.  Action / Activity Actions or activity executed during the transition.  Symbol event [ guard ] / action

Elements of State Diagram  Initial State: The initial state is the starting state of the object with reference to the behavior that the diagram explains. Each state diagram should have only one initial state.  Symbol:

Elements of State Diagram  Final State: Each final state is the ending state of the object with reference to the behavior that the diagram explains. There may be zero, one or multiple final states for an object.  Symbol: