de.uni_tuebingen.sfb.lichtenstein.formulas
Class SecondOrderQuantor

java.lang.Object
  de.uni_tuebingen.sfb.lichtenstein.formulas.FormulaImpl
      de.uni_tuebingen.sfb.lichtenstein.formulas.ComposedFormula
          de.uni_tuebingen.sfb.lichtenstein.formulas.SecondOrderQuantor

All Implemented Interfaces:

Formula, Quantification, Visitable, Serializable

Direct Known Subclasses:

SecondOrderExistentialQuantification, SecondOrderUniversalQuantification

public abstract class SecondOrderQuantor
extends ComposedFormula
implements Quantification

A class for representing quantors on second order variables, implementing common methods for existential and universal quantors.

Author:

Hendrik Maryns

See Also:

Serialized Form

Method Summary

boolean	containsVariable(Variable var) Returns whether this formula contains the given variable.
boolean	equals(Object other) An object is equal to a quantor if it has the same class (i.e., not only it is a quantor, but it really has the same leaf-level class), the arguments are equal and they bind the same variable.
Formula	getArgument() Returns the formula this quantor acts on.
SecondOrderVariable	getBoundVariable() Returns the variable that is bound by this quantor.
int	getFirstIndexOf(Variable var) Get the first index at which the given variable occurs.
int	getNbBoundVariables() Returns the number of bound variables in this formula.
int	getNbFreeVariables() Returns the number of free variables in this formula.
int	getNbSubformulas() Returns the number of subformulas of this formula.
int	getNbVariables() Returns the number of variables in this formula.
Set<Predicate>	getPredicates() Return all predicates that occur in this formula.
Formula	getSubformulaAt(int index) Returns the indexth subformula of this formula.
Variable	getVariableAt(int index) Get the indexth variable.
int	hashCode() Returns a hash code value for the object.
boolean	isFreeVariable(Variable variable) Check whether the given variable is free in this formula.
String	toString() Returns a string representation of the object.

Methods inherited from class de.uni_tuebingen.sfb.lichtenstein.formulas.ComposedFormula

getAllSubformulas, getSymbol

Methods inherited from class de.uni_tuebingen.sfb.lichtenstein.formulas.FormulaImpl

accept, and, exists, exists, forAll, forAll, getFreeVariables, getVariables, iff, implies, isClosed, not, or

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface de.uni_tuebingen.sfb.lichtenstein.formulas.Formula

and, exists, exists, forAll, forAll, getFreeVariables, getNormalForm, getVariables, iff, implies, isClosed, not, or

Methods inherited from interface de.uni_tuebingen.sfb.lichtenstein.formulas.Visitable

accept

Method Detail

getBoundVariable

public SecondOrderVariable getBoundVariable()

Returns the variable that is bound by this quantor.

Specified by:

getBoundVariable in interface Quantification

getArgument

public Formula getArgument()

Returns the formula this quantor acts on.

Specified by:

getArgument in interface Quantification

getNbVariables

public int getNbVariables()

Returns the number of variables in this formula.

Specified by:

getNbVariables in interface Formula

getNbFreeVariables

public int getNbFreeVariables()

Returns the number of free variables in this formula.

Specified by:

getNbFreeVariables in interface Formula

getNbBoundVariables

public int getNbBoundVariables()

Returns the number of bound variables in this formula.

Specified by:

getNbBoundVariables in interface Formula

getFirstIndexOf

public int getFirstIndexOf(Variable var)

Get the first index at which the given variable occurs.

Specified by:

getFirstIndexOf in interface Formula

Parameters:

var - The variable of which the index is wanted.

getVariableAt

public Variable getVariableAt(int index)
                       throws IndexOutOfBoundsException

Get the indexth variable.

Specified by:

getVariableAt in interface Formula

Parameters:

index - The index of the wanted variable

containsVariable

public boolean containsVariable(Variable var)

Returns whether this formula contains the given variable.

Specified by:

containsVariable in interface Formula

Parameters:

var - The variable to check.

isFreeVariable

public boolean isFreeVariable(Variable variable)

Check whether the given variable is free in this formula.

Specified by:

isFreeVariable in interface Formula

Parameters:

variable - The variable to check.

getPredicates

public Set<Predicate> getPredicates()

Return all predicates that occur in this formula. TODO

Specified by:

getPredicates in interface Formula

getNbSubformulas

public int getNbSubformulas()

Returns the number of subformulas of this formula.

Specified by:

getNbSubformulas in class ComposedFormula

getSubformulaAt

public Formula getSubformulaAt(int index)
                        throws IndexOutOfBoundsException

Returns the indexth subformula of this formula.

Specified by:

getSubformulaAt in class ComposedFormula

Parameters:

index - The index of the wanted subformula. Indices start from 0.

equals

public boolean equals(Object other)

An object is equal to a quantor if it has the same class (i.e., not only it is a quantor, but it really has the same leaf-level class), the arguments are equal and they bind the same variable.

Overrides:

equals in class FormulaImpl

Returns:

If the argument of the other object, viewed as a quantor is not equal to the argument of this quantor, then false.

| let otherQuantor = (Quantor) other in | if ( !
         getArgument().equals(otherQuantor.getArgument()) )
| then result == false

Returns:

If the bound variable of the other object, viewed as a quantor is not equal to the bound variable of this quantor, then false.

| let otherQuantor = (Quantor) other in | if ( ! getBoundVariable() ==
         otherQuantor.getBoundVariable()) )
| then result == false

hashCode

public int hashCode()

Returns a hash code value for the object.

Specified by:

hashCode in class FormulaImpl

Returns:

The hash code is based on the hash codes of the bound variable, the argument and the characteristic symbol. This last one is needed to make the difference between the various subclasses.

| result ==
         getSymbol().hashCode() + getBoundVariable().hashCode() +
| getArgument().hashCode()

toString

public String toString()

Returns a string representation of the object.

Specified by:

toString in class FormulaImpl

Returns:

The string representation of a quantor is the string representation of its arguments with an appropriate sign in between.

| result == "(" + getSymbol() + getBoundVariable().toString() | + ")(" +
         getArgument().toString() + ")"