ai.krr.fol
Class KnowledgeBase

java.lang.Object
  ai.krr.fol.KnowledgeBase

All Implemented Interfaces:

inf.compilers.SyntaxAdaptable

public class KnowledgeBase
extends java.lang.Object
implements inf.compilers.SyntaxAdaptable

A KnowledgeBase is effectively a set of Sentences believed to be true.

Author:

Gerhard Wickler

Field Summary

protected java.util.List<Sentence>

beliefs the List of Sentences that hold in this KB

Constructor Summary

KnowledgeBase()

Method Summary

void	add(Sentence stmt) This function asserts the given Sentence in this KnowledgeBase.
boolean	entails(Sentence stmt) This function tests whether the given Sentence holds in this KnowledgeBase.
boolean	falsifies(Sentence stmt) This function tests whether the given Sentence does not hold in this KnowledgeBase.
void	prettyPrint(int indent, java.io.Writer w, inf.compilers.SyntaxAdaptor sa)
static KnowledgeBase	read(java.io.Reader r, inf.compilers.SyntaxAdaptor<KnowledgeBase> sa)
void	retract(Sentence stmt) This function deletes the given Sentence from this KnowledgeBase.
void	write(java.io.Writer w, inf.compilers.SyntaxAdaptor sa)

Methods inherited from class java.lang.Object

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

Field Detail

beliefs

protected java.util.List<Sentence> beliefs

the List of Sentences that hold in this KB

Constructor Detail

KnowledgeBase

public KnowledgeBase()

Method Detail

write

public void write(java.io.Writer w,
                  inf.compilers.SyntaxAdaptor sa)
           throws inf.compilers.ExpressivenessException,
                  java.io.IOException

Specified by:

write in interface inf.compilers.SyntaxAdaptable

Throws:

inf.compilers.ExpressivenessException

java.io.IOException

prettyPrint

public void prettyPrint(int indent,
                        java.io.Writer w,
                        inf.compilers.SyntaxAdaptor sa)
                 throws inf.compilers.ExpressivenessException,
                        java.io.IOException

Specified by:

prettyPrint in interface inf.compilers.SyntaxAdaptable

Throws:

inf.compilers.ExpressivenessException

java.io.IOException

add

public void add(Sentence stmt)

This function asserts the given Sentence in this KnowledgeBase.

Parameters:

stmt - the Sentence that is to hold in this KnowledgeBase

retract

public void retract(Sentence stmt)

This function deletes the given Sentence from this KnowledgeBase.

Parameters:

stmt - the Sentence that is not to hold in this KnowledgeBase

entails

public boolean entails(Sentence stmt)

This function tests whether the given Sentence holds in this KnowledgeBase.

Parameters:

stmt - the Sentence that may or may not be true

Returns:

true iff the given Sentence is entailed by this KnowledgeBase

falsifies

public boolean falsifies(Sentence stmt)

This function tests whether the given Sentence does not hold in this KnowledgeBase.

Parameters:

stmt - the Sentence that may or may not be true

Returns:

true iff the negation of the given Sentence is entailed by this KnowledgeBase

read

public static KnowledgeBase read(java.io.Reader r,
                                 inf.compilers.SyntaxAdaptor<KnowledgeBase> sa)
                          throws inf.compilers.ExpressivenessException,
                                 java.text.ParseException,
                                 java.io.IOException

Throws:

inf.compilers.ExpressivenessException

java.text.ParseException

java.io.IOException