State diagram

State diagram

•One way to characterize change in a system is to say that its object change their state in response to events and to time .• When you throw a stick a light changes its state from off to on .•When you click a remote control a television changes its state from showing you one channel to showing you another .• After an appropriate amount of time , a washing machine changes its state from Washing to Rinsing .

•The uml state diagram captures these kind of changes .It presents the states an object can be in along with the transitions between the states and shows the starting point and end point of a sequence of state changes.

•Three frequently used activities are entry(what happens when the system enters a state) ,exit(what happens when the system leaves the state ) and what happens while the system is in the state.•You can add others as necessary.

Guard conditionGuard condition is something when its met transition take place

Here the Screensaving is a guard condition.

The end !!!