Creating NSV-10b Systems State Transition diagrams for NAF 3
You can represent the dynamic behavior associated with a system entity using a state diagram.
A state diagram depicts the behavior of a system over time. This diagram relates the events that the system receives to the states that the system can be in. When an event is received, the next state that the entity enters depends on the current state, as well as the event. The change of state of a system is called a transition. Each transition is labeled with the name of the event that causes it.
Diagrams can be nested to show a particular state in more detail.
1 Create a new state diagram.
2 Add symbols to the diagram to depict the behavior of the system.
Symbols
System Transition
A transition signifies when an object moves from one state to another state when a specified event occurs.
System Synch State
A synch state synchronizes concurrent regions of a superstate. This state is used in conjunction with forks and joins to insure that one region leaves a particular state before another region can enter a particular state.
System Synch Bar
The Synchronization Bar models the splitting or joining of transitions to or from concurrent states in a state diagram or activity diagram.
System State
A state symbol represents a state that an object is in at a particular time. While in the state, the object satisfies some condition, performs some action, or waits for some event.
System Initial State
The initial state symbol is represented by a large black circle. Its label usually contains initial conditions. A transition line is drawn from the initial state symbol to the next state.
System Final State
The final state symbol's label generally indicates final conditions. You can draw transition lines to it from more than one previous state.
System Dynamic Choice Point
This choice point models when one transition path is taken from a choice of many.
Result
Each symbol assigns system nodes and system entities that serve as keys for all states related to this diagram.