net.sf.tweety.lp.asp.syntax

Class DLPNot

java.lang.Object

net.sf.tweety.logics.commons.syntax.ComplexLogicalFormulaAdapter

net.sf.tweety.lp.asp.syntax.DLPElementAdapter

net.sf.tweety.lp.asp.syntax.DLPNot

All Implemented Interfaces:

Formula, ComplexLogicalFormula, LogicStructure, SimpleLogicalFormula, DLPElement

public class DLPNot
extends DLPElementAdapter
implements DLPElement

this class models a default negated literal. in answer set programming, the body of a rule is usually composed of a set of positive and negative literals, where this valuation refers to default negation or negation as failure. when implementing a rule, there are two opportunities: - implement the rule with two distinct lists, representing the sets of positive and negative literals - implement the rule with one set containing super literals, where a super literal can be positive or strictly negated, with or without default negation. the library takes the second approach, which allows more flexibility, but comes at the cost that malformed constructs like "not not a" are not intercepted by the library.

Author:

Tim Janus, Thomas Vengels

Field Summary

Fields

Modifier and Type	Field and Description
(package private) DLPLiteral	lit

Constructor Summary

Constructors

Constructor and Description
DLPNot(DLPLiteral inner)
DLPNot(DLPNot other)

Method Summary

Modifier and Type	Method and Description
DLPNot	clone() Creates a deep copy of this formula
boolean	equals(java.lang.Object obj)
java.util.Set<DLPAtom>	getAtoms() Processes the set of all atoms which appear in this formula
java.util.SortedSet<DLPLiteral>	getLiterals()
java.lang.Class<? extends Predicate>	getPredicateCls()
java.util.Set<DLPPredicate>	getPredicates() Processes the set of all predicates which appear in this formula
FolSignature	getSignature() Returns the signature of the language of this formula.
java.util.Set<Term<?>>	getTerms()
int	hashCode()
boolean	isGround() Checks whether this formula is ground, i.e.
DLPNot	substitute(Term<?> v, Term<?> t) Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.
java.lang.String	toString()

Methods inherited from class net.sf.tweety.logics.commons.syntax.ComplexLogicalFormulaAdapter

containsTermsOfType, exchange, getTerms, isLiteral, isWellFormed, substitute

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.tweety.logics.commons.syntax.interfaces.ComplexLogicalFormula

exchange, isWellFormed, substitute

Methods inherited from interface net.sf.tweety.logics.commons.syntax.interfaces.SimpleLogicalFormula

isLiteral

Methods inherited from interface net.sf.tweety.logics.commons.syntax.interfaces.LogicStructure

containsTermsOfType, getTerms

Field Detail

lit

DLPLiteral lit

Constructor Detail

DLPNot

public DLPNot(DLPLiteral inner)

DLPNot

public DLPNot(DLPNot other)

Method Detail

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Specified by:

hashCode in interface SimpleLogicalFormula

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Specified by:

equals in interface SimpleLogicalFormula

Overrides:

equals in class java.lang.Object

isGround

public boolean isGround()

Description copied from interface: ComplexLogicalFormula

Checks whether this formula is ground, i.e. whether there appears no variable in this formula.

Specified by:

isGround in interface ComplexLogicalFormula

Overrides:

isGround in class ComplexLogicalFormulaAdapter

Returns:

"true" if this formula is ground.

clone

public DLPNot clone()

Description copied from interface: SimpleLogicalFormula

Creates a deep copy of this formula

Specified by:

clone in interface ComplexLogicalFormula

Specified by:

clone in interface SimpleLogicalFormula

Specified by:

clone in interface DLPElement

Specified by:

clone in class DLPElementAdapter

getAtoms

public java.util.Set<DLPAtom> getAtoms()

Description copied from interface: SimpleLogicalFormula

Processes the set of all atoms which appear in this formula

Specified by:

getAtoms in interface SimpleLogicalFormula

Specified by:

getAtoms in interface DLPElement

Returns:

The set of all atoms

getPredicates

public java.util.Set<DLPPredicate> getPredicates()

Description copied from interface: SimpleLogicalFormula

Processes the set of all predicates which appear in this formula

Specified by:

getPredicates in interface SimpleLogicalFormula

Specified by:

getPredicates in interface DLPElement

Returns:

all predicates that appear in this formula

getPredicateCls

public java.lang.Class<? extends Predicate> getPredicateCls()

Specified by:

getPredicateCls in interface SimpleLogicalFormula

Overrides:

getPredicateCls in class DLPElementAdapter

Returns:

The class description of the predicate used by this formula.

getSignature

public FolSignature getSignature()

Description copied from interface: Formula

Returns the signature of the language of this formula.

Specified by:

getSignature in interface Formula

Specified by:

getSignature in interface DLPElement

Returns:

the signature of the language of this formula.

getTerms

public java.util.Set<Term<?>> getTerms()

Specified by:

getTerms in interface LogicStructure

Returns:

a set containing all terms of this logical structure

substitute

public DLPNot substitute(Term<?> v,
                         Term<?> t)
                  throws java.lang.IllegalArgumentException

Description copied from interface: ComplexLogicalFormula

Substitutes all occurrences of term "v" in this formula by term "t" and returns the new formula.

Specified by:

substitute in interface ComplexLogicalFormula

Specified by:

substitute in interface DLPElement

Parameters:

v - the term to be substituted.

t - the term to substitute.

Returns:

a formula where every occurrence of "v" is replaced by "t".

Throws:

java.lang.IllegalArgumentException - if "v" and "t" are of different sorts

getLiterals

public java.util.SortedSet<DLPLiteral> getLiterals()

Specified by:

getLiterals in interface DLPElement

Returns:

all the literals used in the rule element