State Diagram

• Shows the states of an object and the transition between states.
• Use for classes whose objects have interesting, discrete, states.
• Use states to describe user interaction with the system.

States are rounded rectangles. Transitions are arrows from one state to another. Events or conditions that trigger transitions are written beside the arrows. Self-transition are allowed. The action that occurs as a result of an event or condition is expressed in the form /action. Initial & Final states marked (missing from Violet).