de.uni_tuebingen.sfb.lichtenstein.formulas
Class Inclusion

java.lang.Object
  de.uni_tuebingen.sfb.lichtenstein.formulas.FormulaImpl
      de.uni_tuebingen.sfb.lichtenstein.formulas.AtomicFormula
          de.uni_tuebingen.sfb.lichtenstein.formulas.Inclusion

All Implemented Interfaces:

Formula, Visitable, Serializable

public final class Inclusion
extends AtomicFormula

A class representing inclusion of a first order variable in a set denotator.

Author:

Hendrik Maryns

See Also:

Serialized Form

Constructor Summary

Inclusion(FirstOrderVariable included, SetDenotator containing)
Initialize a new inclusion, taking two variables as arguments.

Method Summary

void	accept(FormulaVisitor visitor) Accept a formula visitor.
protected Set<Predicate>	computePredicates() Return all predicates in this formula.
protected Set<Variable>	computeVariables() Simply return the two variables.
boolean	containsVariable(Variable var) Returns whether this formula contains the given variable.
boolean	equals(Object other) Indicates whether some other object is “equal to” this one.
SetDenotator	getContainingVariable() Returns the containing variable.
FirstOrderVariable	getIncludedVariable() Returns the included variable.
int	hashCode() Returns a hash code value for the object.
String	toString() Returns a string representation of the object.

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

getNormalForm, isFree

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

Inclusion

public Inclusion(FirstOrderVariable included,
                 SetDenotator containing)

Initialize a new inclusion, taking two variables as arguments.

Parameters:

included - The variable which is included in the other variable.

containing - The variable which includes the other variable.

Precondition:

Both variables must be effective. | included != null && containing != null

Postconditions:

The included variable is set to the given included variable. | new.getIncludedVariable() == included

The containing variable is set to the given containing variable. | new.getContainingVariable() == containing

Method Detail

getIncludedVariable

public FirstOrderVariable getIncludedVariable()

Returns the included variable.

Returns:

The first variable.

getContainingVariable

public SetDenotator getContainingVariable()

Returns the containing variable.

Returns:

The second variable.

computeVariables

protected Set<Variable> computeVariables()

Simply return the two variables.

Specified by:

computeVariables in class FormulaImpl

Returns:

The two variables in the right order. | result.size() == 2 && | result.contains(getIncludedVariable()) &&
result.contains(getContainingVariable())

containsVariable

public boolean containsVariable(Variable var)

Returns whether this formula contains the given variable.

Parameters:

var - The variable to check.

Returns:

True if the given variable is the same as the included variable. | result == getIncludedVariable().equals(var) || getContainingVariable().equals(var)

computePredicates

protected Set<Predicate> computePredicates()

Return all predicates in this formula.

Specified by:

computePredicates in class FormulaImpl

Returns:

Only the including variable can be a predicate. | if ( getIncludingVariable() instanceof Predicate ) | then result.contains(getContainingVariable()) | else result.isEmpty()

equals

public boolean equals(Object other)

Indicates whether some other object is “equal to” this one.

Overrides:

equals in class FormulaImpl

Returns:

Two inclusion atomic formulas are equal if they compare the same variables. | let otherIn = (Inclusion) other in | if ( otherIn.getIncludedVariable() == getIncludedVariable() ) | then result == false | else if ( otherIn.getContainingVariable() == getContainingVariable() ) | then result == false | else result == true

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 variables and of the characteristic symbol. | result == getIncludedVariable().hashCode() + "∈".hashCode() + getContainingVariable().hashCode()

toString

public String toString()

Returns a string representation of the object.

Specified by:

toString in class FormulaImpl

Returns:

The string representations of the variables are given, with the unicode symbol ELEMENT OF: ∈ in between them. | result == getIncludedVariable().toString() + "∈" + getContainingVariable().toString()

accept

public void accept(FormulaVisitor visitor)
            throws VisitorException

Accept a formula visitor. The iteration is done by the visitor, not by the composed formulas.

Parameters:

visitor - The visitor that is to be accepted to do its work.

Throws:

VisitorException - [CAN] A visitor can throw an exception.