Nice Domains in Domain Testing

Introduction 

State Machines 

State machines indicate the sequences of states an object undergoes in response to events throughout its lifetime 

State machines are used to model 

• the behavior of an individual object 
• the dynamic aspects of a system 

State machines can visualize by,

• highlighting the flow control from activity to activity 
• highlighting the potential states of objects and the transition among those states

Statechart Diagram 

• Shows a state machine, emphasizing the flow of control from state to state 
• Statechart diagram is used to model 

dynamic aspects of a system 

the behavior of reactive objects 

• Important for constructing executable systems through forward and reverse engineering

A state machine refers to a behavior that recognizes the sequence of states an object undergoes in response to events throughout its lifetime.

A state refers to a situation of an object, where it satisfies some conditions, carries out some activity, or waits for some event. 

Name 

• A textual string 

Entry/Exit actions 

• Actions executed on entering and exiting the state 

Internal transitions 

• Transitions that are handled without causing a change in state 

Substates 

• The nested structure of a state 

Deferred events 

• A list of events that are not handled in that state, but are postponed and queued for handling by the object in another state 

Initial and final states 

• Initial state shows the beginning of the state machine and final state shows the ending of the state machine

Transitions 

• A transition is a relationship between two states 
• An object performs certain actions in the first state. It then enters the second state when specified events happen and specified conditions are satisfied 

The parts of transition are: 

Source state: State affected by transition 

Event trigger:  Event whose reception by the object in the source state makes the transition eligible to fire

Guard condition: A Boolean expression that is evaluated when the transition is triggered by the reception of event trigger

Effect: It is a behavior which executes when a transition fires

Action: State that is active after the completion of transition

Target state: An executable atomic computation