net.sf.tweety.lp.asp.syntax

Class Program

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractSet<E>

java.util.HashSet<T>

net.sf.tweety.commons.util.rules.RuleSet<ASPRule>

net.sf.tweety.lp.asp.syntax.Program

All Implemented Interfaces:

Serializable, Cloneable, Iterable<ASPRule>, Collection<ASPRule>, Set<ASPRule>, net.sf.tweety.commons.BeliefBase, net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

public class Program
extends net.sf.tweety.commons.util.rules.RuleSet<ASPRule>
implements net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

This class models an ASP-Core-2 program, meaning a set of rules and optionally a query. A program is ground if it contains no variables. The rules are ordered alphabetically.

Author:

Tim Janus, Thomas Vengels, Anna Gessler

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Program() Creates a new empty program.
Program(ASPLiteral query, Set<ASPRule> rules) Creates a new program with the given query and rules.
Program(Collection<ASPRule> rules) Creates a new program with the given rules.
Program(Program other) Copy-Constructor

Method Summary

Modifier and Type	Method and Description
void	add(Program other) Adds another program's content to the content of this program.
void	addAll(List<ASPRule> rules)
void	addFact(ASPHead fact)
void	addFact(ASPLiteral fact)
Program	clone()
boolean	contains(ASPRule r) Returns true if the program contains a given rule.
static Program	defaultification(Program p) Creates the defaultification p_d of a given program p.
Program	exchange(net.sf.tweety.logics.commons.syntax.interfaces.Term<?> v, net.sf.tweety.logics.commons.syntax.interfaces.Term<?> t)
Set<net.sf.tweety.logics.commons.syntax.Predicate>	getOutputWhitelist() Returns the whitelist of predicates.
ASPLiteral	getQuery() Returns the query of the program, if there is one.
Set<ASPRule>	getRules() Returns all rules of the program.
net.sf.tweety.logics.fol.syntax.FolSignature	getSignature()
boolean	hasQuery() Returns true if the program contains a query.
boolean	isExtendedProgram() Checks if the program is an extended program, meaning the heads of the literals do not have more than one literal.
boolean	isGround()
boolean	isSafe() Returns true if the program is safe, i.e.
Program	reduct(Set<ASPLiteral> state) Returns the reduct of this program wrt.
void	setOutputWhitelist(Collection<net.sf.tweety.logics.commons.syntax.Predicate> ps) Sets the whitelist of predicates.
void	setQuery(ASPLiteral query) Sets the query of the program.
Program	substitute(Map<? extends net.sf.tweety.logics.commons.syntax.interfaces.Term<?>,? extends net.sf.tweety.logics.commons.syntax.interfaces.Term<?>> map)
Program	substitute(net.sf.tweety.logics.commons.syntax.interfaces.Term<?> v, net.sf.tweety.logics.commons.syntax.interfaces.Term<?> t)
String	toString()

Methods inherited from class net.sf.tweety.commons.util.rules.RuleSet

getConclusions, getPremises, getRulesWithConclusion, getSyntacticModule

Methods inherited from class java.util.HashSet

add, clear, contains, isEmpty, iterator, remove, size, spliterator

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, retainAll, toArray, toArray

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

addAll, containsAll, equals, hashCode, removeAll, retainAll, toArray, toArray

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

Program

public Program()

Creates a new empty program.

Program

public Program(Collection<ASPRule> rules)

Creates a new program with the given rules.

Parameters:

query -

rules -

Program

public Program(ASPLiteral query,
               Set<ASPRule> rules)

Creates a new program with the given query and rules.

Parameters:

query -

rules -

Program

public Program(Program other)

Copy-Constructor

Parameters:

other -

Method Detail

setQuery

public void setQuery(ASPLiteral query)

Sets the query of the program.

Parameters:

query - a literal

addFact

public void addFact(ASPHead fact)

Specified by:

addFact in interface net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

getSignature

public net.sf.tweety.logics.fol.syntax.FolSignature getSignature()

Specified by:

getSignature in interface net.sf.tweety.commons.BeliefBase

Specified by:

getSignature in interface net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

substitute

public Program substitute(net.sf.tweety.logics.commons.syntax.interfaces.Term<?> v,
                          net.sf.tweety.logics.commons.syntax.interfaces.Term<?> t)
                   throws IllegalArgumentException

Specified by:

substitute in interface net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

Throws:

IllegalArgumentException

substitute

public Program substitute(Map<? extends net.sf.tweety.logics.commons.syntax.interfaces.Term<?>,? extends net.sf.tweety.logics.commons.syntax.interfaces.Term<?>> map)
                   throws IllegalArgumentException

Specified by:

substitute in interface net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

Throws:

IllegalArgumentException

exchange

public Program exchange(net.sf.tweety.logics.commons.syntax.interfaces.Term<?> v,
                        net.sf.tweety.logics.commons.syntax.interfaces.Term<?> t)
                 throws IllegalArgumentException

Specified by:

exchange in interface net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

Throws:

IllegalArgumentException

toString

public String toString()

Specified by:

toString in interface net.sf.tweety.commons.BeliefBase

Specified by:

toString in interface net.sf.tweety.logics.commons.syntax.interfaces.LogicProgram<ASPHead,ASPBodyElement,ASPRule>

Overrides:

toString in class AbstractCollection<ASPRule>

isGround

public boolean isGround()

clone

public Program clone()

Overrides:

clone in class HashSet<ASPRule>

setOutputWhitelist

public void setOutputWhitelist(Collection<net.sf.tweety.logics.commons.syntax.Predicate> ps)

Sets the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.

Parameters:

ps - set of predicates

getOutputWhitelist

public Set<net.sf.tweety.logics.commons.syntax.Predicate> getOutputWhitelist()

Returns the whitelist of predicates. Solvers that use this option will only show atoms over predicates in this set in their output.

Returns:

set of whitelisted predicates

hasQuery

public boolean hasQuery()

Returns true if the program contains a query.

Returns:

true if the program has a query, false otherwise

getQuery

public ASPLiteral getQuery()

Returns the query of the program, if there is one.

Returns:

a literal, or null if the program has no query

getRules

public Set<ASPRule> getRules()

Returns all rules of the program.

Returns:

set of rules

reduct

public Program reduct(Set<ASPLiteral> state)

Returns the reduct of this program wrt. the given state, i.e. a program that contains no default negation and only those rules of this program (without all default-negated literals in the body) that do not have a default-negated version of a literal in their body.

Parameters:

state - some set of literals

Returns:

the reduct of this program

defaultification

public static Program defaultification(Program p)

Creates the defaultification p_d of a given program p. A defaultificated program p' of p adds for every Rule r in p a modified rule r_d of the form: 'H(r) :- B(r), not -H(r).' to the program p'.

Parameters:

p - The program which is not defaultificated yet

Returns:

a program p' which is the defaultificated version of p.

addFact

public void addFact(ASPLiteral fact)

isExtendedProgram

public boolean isExtendedProgram()

Checks if the program is an extended program, meaning the heads of the literals do not have more than one literal.

Returns:

True if the program is an extended program, false otherwise.

add

public void add(Program other)

Adds another program's content to the content of this program.

Parameters:

other - Reference to the other program.

addAll

public void addAll(List<ASPRule> rules)

contains

public boolean contains(ASPRule r)

Returns true if the program contains a given rule.

Parameters:

r - an ASP rule

Returns:

true if program contains r

isSafe

public boolean isSafe()

Returns true if the program is safe, i.e. if all of its rules and its query are safe.

Returns:

true if the program is safe, false otherwise