uk.ac.sheffield.vtts.model

Class State

java.lang.Object

uk.ac.sheffield.vtts.model.Element

uk.ac.sheffield.vtts.model.Named

uk.ac.sheffield.vtts.model.Annotated

uk.ac.sheffield.vtts.model.Coverable

uk.ac.sheffield.vtts.model.State

public class State
extends Coverable

State represents a named state in a finite state machine. A State is named in "CapitalCase" and is uniquely indexed by this name, within its owning Machine. Each State owns a set of uniquely named exit Transitions, traversing from this State to another State in the same Machine. One State within a Machine may be marked as the initial State.

Version:

Broker@Cloud 1.0

Author:

Anthony J H Simons

Field Summary

Fields inherited from class uk.ac.sheffield.vtts.model.Coverable

covered

Fields inherited from class uk.ac.sheffield.vtts.model.Annotated

notice

Fields inherited from class uk.ac.sheffield.vtts.model.Named

name

Constructor Summary

Constructors

Constructor and Description
State() Creates a default state.
State(java.lang.String name) Creates a named State.

Method Summary

Methods

Modifier and Type	Method and Description
State	addTransition(Transition transition) Adds a named exit Transition to this State.
Notice	checkCompleteness(Notice topInfo, Alphabet alphabet) Checks the completeness of this State with respect to an Alphabet.
Transition	getEnabled(Event event) Returns the exit Transition whose name matches a given event.
java.lang.Boolean	getInitial() Optionally reports whether this is the initial State.
java.lang.String	getName() Returns the name of a State.
Transition	getTransition(java.lang.String name) Returns the unique exit Transition with the given name.
java.util.List<Transition>	getTransitions() Returns the list of exit Transitions for this State.
boolean	isInitial() Reports whether this is the initial State.
State	setInitial(boolean value) Sets whether this is a initial State.
State	snapshot() Takes a snapshot of this State, without its dependent Transitions.

Methods inherited from class uk.ac.sheffield.vtts.model.Coverable

isCovered, setCovered

Methods inherited from class uk.ac.sheffield.vtts.model.Annotated

addNotice, getNotice

Methods inherited from class uk.ac.sheffield.vtts.model.Named

equals, hashCode, setName, setName, toString

Methods inherited from class uk.ac.sheffield.vtts.model.Element

safeEquals, safeHashCode, semanticError

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

State

public State()

Creates a default state.

State

public State(java.lang.String name)

Creates a named State.

Parameters:

name - the name of this State.

Method Detail

getName

public java.lang.String getName()

Returns the name of a State. It is an error if the name has not already been set, when this access method is invoked.

Overrides:

getName in class Named

Returns:

the name.

setInitial

public State setInitial(boolean value)

Sets whether this is a initial State.

Parameters:

value - true, if this is a initial State.

Returns:

this State.

getInitial

public java.lang.Boolean getInitial()

Optionally reports whether this is the initial State. Used during marshalling, where saving this attribute is optional.

Returns:

the Boolean object true, or null.

isInitial

public boolean isInitial()

Reports whether this is the initial State.

Returns:

true if this is the initial State.

addTransition

public State addTransition(Transition transition)

Adds a named exit Transition to this State. Each Transition must be uniquely named. A duplicate Transition will replace an existing Transition with the same name. The Transition's source must match the name of this State. If no source or target are specified, these are set to the name of this State.

Parameters:

transition - the transition to add.

Returns:

this State.

getTransition

public Transition getTransition(java.lang.String name)

Returns the unique exit Transition with the given name.

Parameters:

name - the name of the Transition.

Returns:

the named Transition, or null.

getTransitions

public java.util.List<Transition> getTransitions()

Returns the list of exit Transitions for this State.

Returns:

the list of exit Transitions.

getEnabled

public Transition getEnabled(Event event)

Returns the exit Transition whose name matches a given event.

Parameters:

event - the event.

Returns:

the Transition matching the event, or null.

snapshot

public State snapshot()

Takes a snapshot of this State, without its dependent Transitions. This is used when generating a Warning about this State, to report that it has not been covered.

Returns:

a clone of this State, without its Transitions.

checkCompleteness

public Notice checkCompleteness(Notice topInfo,
                       Alphabet alphabet)

Checks the completeness of this State with respect to an Alphabet. Creates a Notice for this State describing its completeness with respect to the given Alphabet. Attaches a Warning if this State is unreachable (after simulation of its Machine); and an Analysis listing any Events that are ignored. Also attaches summary Warning and Analysis nodes to the topInfo Notice.

Parameters:

topInfo - the top-level Notice.

alphabet - the Alphabet of the associated Machine.

Returns:

the Notice describing the completeness check.