prolog.model
Interface IFactDb

All Known Implementing Classes:

FactDb

public interface IFactDb

This class represent the complete fact database. in this class, facts are stored as relations in factlists. this factlists are ordered by the fact's name. A fact database can be used to prove facts a unsafe fact.

Method Summary

void	add(IFact f) adds the given fact to the fact database. first the database is queries for a factlist with the name of the given fact. if one was found, the relation of the given fact is stored. if no one was found, a new factlist is created in which the relation is stored.
void	add(IRelation relation, int name) adds a new relation to the fact database under the given name. first the database is queries for a factlist matching name. if one was found, the relation is stored in.
void	clear() clears the fact database
void	genXml(java.io.Writer out, ISymbolTable table) generates a xml representation of this fact database
IFactList	getFactList(int key) returns the factlist for the given name
java.util.Iterator	getFactLists()
boolean	isFact(IFact f) queries the database for a fact. it returns true, if a fact in database is found matching the given one. first, the database is queried for a factlist with the given name. if on was found, this list is iterated finding a fact matching the given facts.
java.lang.String	toString(ISymbolTable table) returns a string representation with decoded symbols

Method Detail

clear

public void clear()

clears the fact database

getFactList

public IFactList getFactList(int key)

returns the factlist for the given name

Parameters:

key - the name of the fact to search for

Returns:

the factlist matching the given key

add

public void add(IFact f)

adds the given fact to the fact database. first the database is queries for a factlist with the name of the given fact. if one was found, the relation of the given fact is stored. if no one was found, a new factlist is created in which the relation is stored.

Parameters:

f - is the fact to be added

add

public void add(IRelation relation,
                int name)

adds a new relation to the fact database under the given name. first the database is queries for a factlist matching name. if one was found, the relation is stored in. If no one was found, a new factlist is created in which the relation is stored.

Parameters:

relation - is the relation to be added

name - is the name of the relation

isFact

public boolean isFact(IFact f)
               throws ParameterMatchingError

queries the database for a fact. it returns true, if a fact in database is found matching the given one. first, the database is queried for a factlist with the given name. if on was found, this list is iterated finding a fact matching the given facts. If one was found, this method returns true, in all other cases false. If it returns true, the given fact is proven.

Parameters:

f - is the fact to test

Returns:

true if the given fact is true

genXml

public void genXml(java.io.Writer out,
                   ISymbolTable table)
            throws java.io.IOException

generates a xml representation of this fact database

Parameters:

out - is the writer where to append the xml

table -

Throws:

java.io.IOException -

toString

public java.lang.String toString(ISymbolTable table)

returns a string representation with decoded symbols

Parameters:

table - is the symboltable to decode

Returns:

a string representation ;-)

getFactLists

public java.util.Iterator getFactLists()

Returns:

a iterator over all stored factlists