/*******************************************************************************
* Copyright (c) 2009, 2011 SAP AG and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* SAP AG - initial API and implementation
******************************************************************************/
package org.eclipse.ocl.examples.eventmanager.util;
import java.util.Set;
/**
* A composite collection that has unique entries only. Clients need to assert this property by themselves
* because only this way can we save the effort of actually iterating all elements of all sets which is the
* whole purpose of this class.
*
* @author Axel Uhl (D043530)
*/
public class CompositeSet<E> extends CompositeCollection<E> implements Set<E> {
private Integer hashCode = null;
public CompositeSet(Set<? extends E>... sets) {
super(sets);
}
public boolean equals(Object o) {
if (!(o instanceof Set<?>)) {
return false;
}
Set<?> otherSet = (Set<?>) o;
for (E e : this) {
if (!otherSet.contains(e)) {
return false;
}
}
return true;
}
public int hashCode() {
if (hashCode != null) {
return hashCode;
} else {
int hc = 92748;
for (E e : this) {
hc ^= e.hashCode();
}
hashCode = hc;
return hc;
}
}
}