Package org.tweetyproject.action.transitionsystem

Class TransitionSystem

java.lang.Object

org.tweetyproject.action.transitionsystem.TransitionSystem

public class TransitionSystem
extends Object

This class represents an action transition system for a fixed action signature with a set of states and a set of transitions between states. Transition systems are used to capture the meaning of action descriptions. For a collection of action languages defined in terms of transition systems, see: [Gelfond, Michael and Lifschitz, Vladimir: Action Languages. ETAI: Electronic Transactions on AI, 1998.]

Author:

Sebastian Homann

Constructor Summary

Constructors

Constructor	Description
TransitionSystem(Set<State> states, Set<Transition> transitions, ActionSignature signature)	Creates a new transition system.
TransitionSystem(Set<State> states, ActionSignature signature)	Creates a new transition system.
TransitionSystem(ActionSignature signature)	Creates a new empty transition system with the given ActionSignature.

Method Summary

Modifier and Type	Method	Description
State	addState(Set<FolAtom> fluents)	Creates a new state and adds it to this transition system.
void	addState(State s)	Adds a state to this transition system.
void	addTransition(Transition t)	Adds a given transition to this transition system.
ActionSignature	getSignature()	Returns the action signature of this transition system.
State	getState(Set<FolAtom> fluents)	Returns the state that maps the given fluents to true, if it exists, otherwise null.
Set<State>	getStates()	Creates a HashSet with all states contained in this transition system.
Set<Transition>	getTransitions()	Creates a HashSet with all transitions contained in this transition system.
boolean	getValue(FolAtom fluent, State state)	Returns the value of a fluent in a state in this transition system.
String	toDotFormat()	Returns this transition system in dot-format with collapsed transitions, which may be further processed using a graph drawing library such as graphviz.
String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

TransitionSystem

public TransitionSystem(Set<State> states,
 Set<Transition> transitions,
 ActionSignature signature)

Creates a new transition system.

Parameters:

states - A set of states which is contained in this transition system.

transitions - A set of transitions which is contained in this transition system.

signature - The action signature for this transition system.

TransitionSystem

public TransitionSystem(Set<State> states,
 ActionSignature signature)

Creates a new transition system.

Parameters:

states - A set of states which is contained in this transition system.

signature - The action signature for this transition system.

TransitionSystem

public TransitionSystem(ActionSignature signature)

Creates a new empty transition system with the given ActionSignature.

Parameters:

signature - the action signature of this transition system

Method Details

addState

public State addState(Set<FolAtom> fluents)

Creates a new state and adds it to this transition system.

Parameters:

fluents - The set of fluents which are to be mapped to true by the new state.

Returns:

the new state which maps the given fluents to true.

addState

public void addState(State s)

Adds a state to this transition system.

Parameters:

s - a new state

getState

public State getState(Set<FolAtom> fluents)

Returns the state that maps the given fluents to true, if it exists, otherwise null.

Parameters:

fluents - a set of fluents

Returns:

the state that maps the given fluents to true, if it exists, otherwise null.

addTransition

public void addTransition(Transition t)

Adds a given transition to this transition system.

Parameters:

t - a new transition

getStates

public Set<State> getStates()

Creates a HashSet with all states contained in this transition system.

Returns:

all states contained in this transition system.

getTransitions

public Set<Transition> getTransitions()

Creates a HashSet with all transitions contained in this transition system.

Returns:

all transitions contained in this transition system.

getValue

public boolean getValue(FolAtom fluent,
 State state)

Returns the value of a fluent in a state in this transition system.

Parameters:

fluent - a fluent

state - a state

Returns:

true, iff the fluent is mapped to true by the given state.

toDotFormat

public String toDotFormat()

Returns this transition system in dot-format with collapsed transitions, which may be further processed using a graph drawing library such as graphviz. For more information, see http://www.graphviz.org

Returns:

This transition system in dot format.

getSignature

public ActionSignature getSignature()

Returns the action signature of this transition system.

Returns:

the action signature of this transition system.

toString

public String toString()

Overrides:

toString in class Object