jdrew.oo.td.builtins
Class AssertBuiltin

java.lang.Object
  jdrew.oo.td.builtins.TDBuiltin
      jdrew.oo.td.builtins.AssertBuiltin

public class AssertBuiltin
extends TDBuiltin

The class implements a "builtin" for asserting a new clause into the running knowledge base. While this would not normally be considered a built-in relation it is implement as such to provide for easy implementation.

This built-in extends the jdrew.oo.td.builtins.TDBuiltin Class, instead of implementing the jdrew.oo.builtins.Builtin Interface as it requires access to data structures that are not available to it when implementing a regular built-in and also it does not work across both bottom-up and top-down, but is instead specific to bottom-up.

Title: OO jDREW

Description: Reasoning Engine for the Semantic Web - Supporting OO RuleML 0.88

Copyright: Copyright (c) 2005

Version:

0.89

Author:

Marcel A. Ball

Constructor Summary

AssertBuiltin(BackwardReasoner br)
Constructs a new object to implement the assert built-in relation.

Method Summary

DefiniteClause	buildResult(BackwardReasoner.GoalList gl, int term) This method performs the actions necessary to implement the assert built-in relation.
int	getSymbol() Access the symbol code for the assert built-in relation.

Methods inherited from class java.lang.Object

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

Constructor Detail

AssertBuiltin

public AssertBuiltin(BackwardReasoner br)

Constructs a new object to implement the assert built-in relation. This constructor must be passed a reference to the backward reasoner object that the built-in will be registered in.

Parameters:

br - BackwardReasoner - The backward reasoner engine that will register this built-in relationship.

Method Detail

getSymbol

public int getSymbol()

Access the symbol code for the assert built-in relation.

Overrides:

getSymbol in class TDBuiltin

Returns:

int The symbol code for the assert built-in relation.

buildResult

public DefiniteClause buildResult(BackwardReasoner.GoalList gl,
                                  int term)

This method performs the actions necessary to implement the assert built-in relation. This will assert the clause that is the parameter to the assert into the running knowledge base and cause the goal to succeed.

Overrides:

buildResult in class TDBuiltin

Parameters:

gl - GoalList goal list that contains the call to the assert built-in relation.

term - int An index into the atoms (array) of the clause (0 is the head, i = 1..n is the ith atom of the body of the clause) to the atom that is the call to the assert built-in relation.

Returns:

DefiniteClause A clause that will successfully unify with the call to the built-in if it should succeed. null or a fact that will not unify (null is preferred as it is more efficient) should be returned if the call to built-in relation should not succeed.