logic
Class Formula

java.lang.Object
  logic.Formula

Direct Known Subclasses:

AtomicProposition, LogicalAnd, LogicalNot, LogicalOr, ProbabilisticNext, True

public abstract class Formula
extends java.lang.Object

Formula

This abstract class represents a basic formula. The binary operators AND and OR have to subformulas attaches, the unary operator NOT has one, while the True clause has none.

Copyright(c) 2005 Université Laval, LSFM research group.

Version:

1.0

Author:

Nicolas Richard

Field Summary

protected Formula[]

subFormula

Constructor Summary

Formula()
Constructor with no subformula, for the True clause.

Formula(Formula subFormula)
Constructor with one subformula, for logical operator NOT.

Formula(Formula subFormula1, Formula subFormula2)
Constructor with two subformulas, for logical operators AND and NOT.

Method Summary

int	depth() Current formula's depth.
boolean	equals(java.lang.Object o) Determines if the provided object is a formula equal to this one
Formula[]	getSubFormula() Access the subformula(s) of the current fomula
abstract java.lang.String	getType() This function must be implemented by subclasses
void	setSubFormula(Formula[] subFormula) Sets the current subformulas of this logical operator
java.lang.String	toString() Converting this formula into a string

Methods inherited from class java.lang.Object

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

Field Detail

subFormula

protected Formula[] subFormula

Constructor Detail

Formula

public Formula()

Constructor with no subformula, for the True clause.

Formula

public Formula(Formula subFormula)

Constructor with one subformula, for logical operator NOT.

Parameters:

subFormula - the attached subformula

Formula

public Formula(Formula subFormula1,
               Formula subFormula2)

Constructor with two subformulas, for logical operators AND and NOT.

Parameters:

subFormula1 - the left subformula

subFormula2 - the right subformula

Method Detail

getSubFormula

public Formula[] getSubFormula()

Access the subformula(s) of the current fomula

Returns:

an array of subformulas

setSubFormula

public void setSubFormula(Formula[] subFormula)

Sets the current subformulas of this logical operator

Parameters:

subFormula - an array of subformulas to attach

depth

public int depth()

Current formula's depth. Computed from the number of subformulas under this one. The algorithm is equivalent to comptation of a tree's height.

Returns:

the number of subformulas under this formula.

equals

public boolean equals(java.lang.Object o)

Determines if the provided object is a formula equal to this one

Overrides:

equals in class java.lang.Object

Parameters:

o - the object to compare

Returns:

'True' if the object is a formula equivalent to this one, 'False' otherwise.

toString

public java.lang.String toString()

Converting this formula into a string

Overrides:

toString in class java.lang.Object

Returns:

a string representing the formula

getType

public abstract java.lang.String getType()

This function must be implemented by subclasses

Returns:

a string representing the formula