Package org.tweetyproject.logics.dl.syntax

Class AtomicConcept

java.lang.Object

org.tweetyproject.logics.dl.syntax.ComplexConcept

org.tweetyproject.logics.dl.syntax.AtomicConcept

All Implemented Interfaces:

Formula, ClassicalFormula, Conjunctable, Disjunctable, Invertable, ProbabilityAware, SimpleLogicalFormula

public class AtomicConcept
extends ComplexConcept

This class models an atomic concept (aka concept name) in description logics.
Note: Concept assertions like a:C ("the Individual a is in the extension of the Concept C") are modeled with a different class: ConceptAssertion.

Author:

Anna Gessler

Constructor Summary

Constructors

Constructor	Description
AtomicConcept(String name)	Initializes an atomic concept with the given name.
AtomicConcept(Predicate p)	Initializes an atomic concept with the given predicate.

Method Summary

Modifier and Type	Method	Description
ComplexConcept	clone()	Clones this atomic concept.
AtomicConcept	collapseAssociativeFormulas()	Collapses associative formulas.
boolean	equals(Object obj)	Compares this atomic concept to another object for equality.
String	getName()	Returns the name of this atomic concept.
Predicate	getPredicate()	Returns the predicate representing this atomic concept.
Set<Predicate>	getPredicates()	Returns the set of predicates used in this atomic concept, which in this case is the singleton set containing the predicate representing this concept.
DlSignature	getSignature()	Returns the description logic signature for this atomic concept, which includes the predicate representing this concept.
int	hashCode()	Computes the hash code for this atomic concept based on its predicate.
boolean	isLiteral()	Indicates whether this concept is a literal.
String	toString()	Returns a string representation of this atomic concept.

Methods inherited from class org.tweetyproject.logics.dl.syntax.ComplexConcept

combineWithAnd, combineWithOr, complement, getAtoms, getPredicateCls, getUniformProbability

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Details

AtomicConcept

public AtomicConcept(String name)

Initializes an atomic concept with the given name.

Parameters:

name - the name of the atomic concept

AtomicConcept

public AtomicConcept(Predicate p)

Initializes an atomic concept with the given predicate.

Parameters:

p - the predicate representing the atomic concept; must have arity 1

Throws:

IllegalArgumentException - if the predicate's arity is not 1

Method Details

getPredicate

public Predicate getPredicate()

Returns the predicate representing this atomic concept.

Returns:

the predicate representing this atomic concept

getName

public String getName()

Returns the name of this atomic concept.

Returns:

the name of this atomic concept

getPredicates

public Set<Predicate> getPredicates()

Returns the set of predicates used in this atomic concept, which in this case is the singleton set containing the predicate representing this concept.

Specified by:

getPredicates in interface SimpleLogicalFormula

Specified by:

getPredicates in class ComplexConcept

Returns:

a set containing the predicate of this atomic concept

clone

public ComplexConcept clone()

Clones this atomic concept.

Specified by:

clone in interface SimpleLogicalFormula

Specified by:

clone in class ComplexConcept

Returns:

a clone of this atomic concept

toString

public String toString()

Returns a string representation of this atomic concept.

Overrides:

toString in class Object

Returns:

the name of this atomic concept as a string

collapseAssociativeFormulas

public AtomicConcept collapseAssociativeFormulas()

Collapses associative formulas. For atomic concepts, this method simply returns the current object, as atomic concepts cannot be further collapsed.

Specified by:

collapseAssociativeFormulas in class ComplexConcept

Returns:

this atomic concept

isLiteral

public boolean isLiteral()

Indicates whether this concept is a literal.

Returns:

true, since atomic concepts are considered literals

getSignature

public DlSignature getSignature()

Returns the description logic signature for this atomic concept, which includes the predicate representing this concept.

Specified by:

getSignature in interface Formula

Specified by:

getSignature in class ComplexConcept

Returns:

the signature of this atomic concept

hashCode

public int hashCode()

Computes the hash code for this atomic concept based on its predicate.

Specified by:

hashCode in interface SimpleLogicalFormula

Specified by:

hashCode in class ComplexConcept

Returns:

the hash code of this atomic concept

equals

public boolean equals(Object obj)

Compares this atomic concept to another object for equality. Two atomic concepts are considered equal if their predicates are equal.

Specified by:

equals in interface SimpleLogicalFormula

Specified by:

equals in class ComplexConcept

Parameters:

obj - the object to compare this atomic concept with

Returns:

true if the two atomic concepts are equal, false otherwise