Appears as within state symbol entry / actionName Exit action Action system always performs Immediately before leaving state Appears as within state symbol exit / actionName Deferred event Event that is on interest to system Handling deferred until system reaches another state Appears as within state symbol eventName / Such events get put into queue When system changes state Composite States States we've looked at so far Called simple states UML extends notion of simple state to include Multiple nested states - called composite states These come in several varieties Sequential States If the system exists in A composite state and Only one of the state's substates at a time Substates called sequential substates We can have transitions between such substates As we've seen for full states Using sequential substates We can decompose behaviour of state into smaller pieces History States When system makes transition into composite state Assumed that flow of control
Appears as entry / actionName within state symbol Exit action Action system always performs Immediately before leaving state Appears as exit / actionName within state symbol Deferred event Event that is on interest to system Handling deferred until system reaches another state Appears as eventName / within state symbol Such events get put into queue When system changes state Composite States States we've looked at so far Called simple states UML extends notion of simple state to include Multiple nested states - called composite states These come in several varieties Sequential States If the system exists in A composite state and Only one of the state's substates at a time Substates called sequential substates We can have transitions between such substates As we've seen for full states Using sequential substates We can decompose behaviour of state into smaller pieces History States When system makes transition into composite state Assumed that flow of control