net.sf.tweety.action.transitionsystem

Class TransitionSystem

java.lang.Object

net.sf.tweety.action.transitionsystem.TransitionSystem

public class TransitionSystem
extends java.lang.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

Field Summary

Fields

Modifier and Type	Field and Description
private ActionSignature	signature
private java.util.Set<State>	states
private java.util.Set<Transition>	transitions

Constructor Summary

Constructors

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

Method Summary

Modifier and Type	Method and Description
State	addState(java.util.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(java.util.Set<FOLAtom> fluents) Returns the state that maps the given fluents to true, if it exists, otherwise null.
java.util.Set<State>	getStates() Returns all states contained in this transition system.
java.util.Set<Transition>	getTransitions() Returns 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.
java.lang.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.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

states

private java.util.Set<State> states

transitions

private java.util.Set<Transition> transitions

signature

private ActionSignature signature

Constructor Detail

TransitionSystem

public TransitionSystem(java.util.Set<State> states,
                        java.util.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(java.util.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 Detail

addState

public State addState(java.util.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(java.util.Set<FOLAtom> fluents)

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

Parameters:

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 java.util.Set<State> getStates()

Returns all states contained in this transition system.

Returns:

all states contained in this transition system.

getTransitions

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

Returns 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 java.lang.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 java.lang.String toString()

Overrides:

toString in class java.lang.Object