revisionlogic
Class HSet

java.lang.Object
  java.util.AbstractCollection
      java.util.AbstractSet
          java.util.HashSet
              revisionlogic.HSet

All Implemented Interfaces:

java.lang.Cloneable, java.util.Collection, java.io.Serializable, java.util.Set

class HSet

extends java.util.HashSet

Class HSet is a more specific HashSet that performs further checking when adding an element. It represents the clauses of either a conjunction or a disjunction. For a conjunction, if one of its conjuncts is the negation of another conjunct, the conjunction is transformed into a contradiction. For a disjunction, if one of its disjuncts is the negation of another disjunct, the disjunction is transformed into a tautology.

Author:

Daphne Liu, daphnel@sfu.ca

Field Summary

(package private) ISent

refStatic A reference to a tautology for disjunctive clauses, or to a contradiction for conjunctive clauses.

Fields inherited from class java.util.HashSet

Constructor Summary

(package private)

HSet(int type) Constructs a new HSet of type _type clauses.

Method Summary

boolean	add(java.lang.Object o) Adds an element o to this HSet.
boolean	addAll(java.util.Vector c) Adds each element of the collection c to this HSet.

Methods inherited from class java.util.HashSet

clear, clone, contains, isEmpty, iterator, remove, size

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Set

addAll, containsAll, equals, hashCode, removeAll, retainAll, toArray, toArray

Field Detail

refStatic

ISent refStatic

A reference to a tautology for disjunctive clauses, or to a contradiction for conjunctive clauses.

Constructor Detail

HSet

HSet(int type)

Constructs a new HSet of type _type clauses.

Method Detail

add

public boolean add(java.lang.Object o)

Adds an element o to this HSet.

Returns:

false if o is null or if the negation of o is already in this HSet, true otherwise.

addAll

public boolean addAll(java.util.Vector c)

Adds each element of the collection c to this HSet.

Returns:

false if an element is null or if the negation of an element is already in this HSet, true otherwise.