vishnu.model.algebra
Class Union

java.lang.Object
  vishnu.model.algebra.AbstractBinaryRelation
      vishnu.model.algebra.Union

All Implemented Interfaces:

BinaryRelation, Relation

public class Union
extends AbstractBinaryRelation

Author:

Mariano Tepper

Nested Class Summary

Nested classes/interfaces inherited from interface vishnu.model.algebra.Relation

Relation.Context, Relation.ContextNotSelectedException

Field Summary

Fields inherited from class vishnu.model.algebra.AbstractBinaryRelation

r, s

Constructor Summary

Union(Relation r, Relation s)
Creates a new instance of Union

Method Summary

protected void	operateOn()
void	perform(Relation.Context c) Ejecuta la relacion binaria.
java.lang.String	toString()

Methods inherited from class vishnu.model.algebra.AbstractBinaryRelation

algorithm, algorithm, debugging, hasChanged, leftRelation, leftRelation, rightRelation, rightRelation, setChanged, setContext, signature

Methods inherited from class java.lang.Object

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

Constructor Detail

Union

public Union(Relation r,
             Relation s)

Creates a new instance of Union

Method Detail

operateOn

protected void operateOn()

perform

public void perform(Relation.Context c)

Description copied from class: AbstractBinaryRelation

Ejecuta la relacion binaria. Se encarga de disparar la ejecucion de las relaciones de la izquierda y la derecha y pasar la ejecucion al algoritmo asignado para la relacion. Ademas, se encarga de liberar las tablas anonimas de los operandos una vez ejecutado el algoritmo.

Specified by:

perform in interface Relation

Overrides:

perform in class AbstractBinaryRelation

Parameters:

c - - el contexto de ejecución de la relacion.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object