org.mindswap.pellet.tbox.impl

Class TBoxExpImpl

java.lang.Object

org.mindswap.pellet.tbox.impl.TBoxExpImpl

All Implemented Interfaces:

TBox

public class TBoxExpImpl
extends Object
implements TBox

Title: Implementation of TBox interface to generate explanations efficiently and correctly.

Description:

Copyright: Copyright (c) 2007

Company: Clark & Parsia, LLC.

Author:

Evren Sirin

Field Summary

Fields

Modifier and Type	Field and Description
protected Set<aterm.ATermAppl>	classes
protected KnowledgeBase	kb
static Logger	log
TgBox	Tg
TuBox	Tu

Constructor Summary

Constructors

Constructor and Description
TBoxExpImpl(KnowledgeBase kb)

Method Summary

Modifier and Type	Method and Description
void	absorb()
protected boolean	absorbNominals(aterm.ATermAppl axiom, Set<aterm.ATermAppl> explain)
boolean	addAxiom(aterm.ATermAppl axiom) Add a TBox axiom.
protected boolean	addAxiom(aterm.ATermAppl axiom, Set<aterm.ATermAppl> explain, boolean forceAddition)
protected boolean	addAxiomExplanation(aterm.ATermAppl axiom, Set<aterm.ATermAppl> explain) Add a new explanation for the given axiom.
boolean	addClass(aterm.ATermAppl term) Add a named class declaration
boolean	containsAxiom(aterm.ATermAppl axiom)
Collection<aterm.ATermAppl>	getAbsorbedAxioms()
Set<aterm.ATermAppl>	getAllClasses() Return all the named classes plus TOP and BOTTOM
Collection<aterm.ATermAppl>	getAssertedAxioms() Return all the asserted axioms in this TBox
Set<aterm.ATermAppl>	getAxiomExplanation(aterm.ATermAppl axiom) Return a single explanation for the given TBox axiom.
Set<Set<aterm.ATermAppl>>	getAxiomExplanations(aterm.ATermAppl axiom) Return multiple explanations for the given TBox axiom.
Collection<aterm.ATermAppl>	getAxioms() Return all the axioms defined in this TBox (may include new axioms introduced during absorption)
Collection<aterm.ATermAppl>	getAxioms(aterm.ATermAppl term) Return all the sub and equivalent class axioms that have the given concept on the left hand side
Set<aterm.ATermAppl>	getClasses() Return all the named classes
KnowledgeBase	getKB()
boolean	isPrimitive(aterm.ATermAppl c) Returns if a concept has only primitive definitions in this TBox.
void	prepare() Make any preparation necessary before reasoning.
void	print()
void	print(Appendable str)
boolean	removeAxiom(aterm.ATermAppl axiom) Remove axiom from TBox and all other axioms that depend on it.
boolean	removeAxiom(aterm.ATermAppl dependantAxiom, aterm.ATermAppl explanationAxiom) Remove all explanations for dependantAxiom that contain explanationAxiom.
String	toString()
Iterator<Unfolding>	unfold(aterm.ATermAppl c) Lazy unfold the given concept

Methods inherited from class java.lang.Object

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

Field Detail

log

public static Logger log

kb

protected KnowledgeBase kb

classes

protected Set<aterm.ATermAppl> classes

Tu

public TuBox Tu

Tg

public TgBox Tg

Constructor Detail

TBoxExpImpl

public TBoxExpImpl(KnowledgeBase kb)

Method Detail

getKB

public KnowledgeBase getKB()

getAllClasses

public Set<aterm.ATermAppl> getAllClasses()

Description copied from interface: TBox

Return all the named classes plus TOP and BOTTOM

Specified by:

getAllClasses in interface TBox

getAxiomExplanations

public Set<Set<aterm.ATermAppl>> getAxiomExplanations(aterm.ATermAppl axiom)

Description copied from interface: TBox

Return multiple explanations for the given TBox axiom.

Specified by:

getAxiomExplanations in interface TBox

Returns:

getAxiomExplanation

public Set<aterm.ATermAppl> getAxiomExplanation(aterm.ATermAppl axiom)

Description copied from interface: TBox

Return a single explanation for the given TBox axiom.

Specified by:

getAxiomExplanation in interface TBox

Returns:

addAxiomExplanation

protected boolean addAxiomExplanation(aterm.ATermAppl axiom,
                                      Set<aterm.ATermAppl> explain)

Add a new explanation for the given axiom. If a previous explanation exists this will be stored as another explanation.

Parameters:

axiom -

explain -

Returns:

addAxiom

public boolean addAxiom(aterm.ATermAppl axiom)

Description copied from interface: TBox

Add a TBox axiom.

Specified by:

addAxiom in interface TBox

Returns:

absorbNominals

protected boolean absorbNominals(aterm.ATermAppl axiom,
                                 Set<aterm.ATermAppl> explain)

addAxiom

protected boolean addAxiom(aterm.ATermAppl axiom,
                           Set<aterm.ATermAppl> explain,
                           boolean forceAddition)

removeAxiom

public boolean removeAxiom(aterm.ATermAppl axiom)

Description copied from interface: TBox

Remove axiom from TBox and all other axioms that depend on it. An axiom depends on another axiom if it is a syntactic transformation (as in disjoint axiom is transformed into subclass) or it is obtained via absorption (as equivalent class axioms are absorbed into subclass axioms). This method is syntactic sugar for TBox.removeAxiom(ATermAppl, ATermAppl) where both parameters are axiom.

Specified by:

removeAxiom in interface TBox

Returns:

removeAxiom

public boolean removeAxiom(aterm.ATermAppl dependantAxiom,
                           aterm.ATermAppl explanationAxiom)

Description copied from interface: TBox

Remove all explanations for dependantAxiom that contain explanationAxiom. If no explanations remain, dependantAxiom is removed and all axioms which depend on it are updated (and will be removed if they have no additional explanations).

Specified by:

removeAxiom in interface TBox

Returns:

getAxioms

public Collection<aterm.ATermAppl> getAxioms()

Description copied from interface: TBox

Return all the axioms defined in this TBox (may include new axioms introduced during absorption)

Specified by:

getAxioms in interface TBox

getAssertedAxioms

public Collection<aterm.ATermAppl> getAssertedAxioms()

Description copied from interface: TBox

Return all the asserted axioms in this TBox

Specified by:

getAssertedAxioms in interface TBox

getAbsorbedAxioms

public Collection<aterm.ATermAppl> getAbsorbedAxioms()

containsAxiom

public boolean containsAxiom(aterm.ATermAppl axiom)

absorb

public void absorb()

print

public void print()

toString

public String toString()

Overrides:

toString in class Object

print

public void print(Appendable str)

addClass

public boolean addClass(aterm.ATermAppl term)

Description copied from interface: TBox

Add a named class declaration

Specified by:

addClass in interface TBox

Returns:

true if TBox changed as a result of this call

getClasses

public Set<aterm.ATermAppl> getClasses()

Description copied from interface: TBox

Return all the named classes

Specified by:

getClasses in interface TBox

getAxioms

public Collection<aterm.ATermAppl> getAxioms(aterm.ATermAppl term)

Description copied from interface: TBox

Return all the sub and equivalent class axioms that have the given concept on the left hand side

Specified by:

getAxioms in interface TBox

prepare

public void prepare()

Description copied from interface: TBox

Make any preparation necessary before reasoning.

Specified by:

prepare in interface TBox

unfold

public Iterator<Unfolding> unfold(aterm.ATermAppl c)

Description copied from interface: TBox

Lazy unfold the given concept

Specified by:

unfold in interface TBox

Returns:

isPrimitive

public boolean isPrimitive(aterm.ATermAppl c)

Description copied from interface: TBox

Returns if a concept has only primitive definitions in this TBox. Only primitive definitions mean the concept did not have any equivalents defined or all equivalence axioms has been absorbed into primitive definitions. This function returns false for complex class expressions.

Specified by:

isPrimitive in interface TBox

Parameters:

c - a concept (named concept or a concept expression)

Returns:

true if the concept is not complex and has only primitive definitions