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The basic runtime tools and interfaces for intarsys components.

There is a newer version: 4.11

/*
 * Copyright (c) 2007, intarsys consulting GmbH
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 *
 * - Neither the name of intarsys nor the names of its contributors may be used
 *   to endorse or promote products derived from this software without specific
 *   prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package de.intarsys.tools.collection;

import java.util.Enumeration;
import java.util.NoSuchElementException;

/**
 * An Enumeration without elements.
 */
public class EmptyEnumeration implements Enumeration {
	//
	public final static Enumeration UNIQUE = new EmptyEnumeration();

	/**
	 * Create an emtpy enumeration
	 */
	protected EmptyEnumeration() {
		super();
	}

	/**
	 * Return always false as an emtpy enumeration has no elements.
	 * 
	 * @return Return always false as an emtpy enumeration has no elements.
	 */
	public boolean hasMoreElements() {
		return false;
	}

	/**
	 * Throw always exception, as an empty enumeration has no elements.
	 * 
	 * @return never
	 * 
	 * @throws NoSuchElementException
	 *             Is thrown always
	 */
	public java.lang.Object nextElement() {
		throw new NoSuchElementException("no element available");
	}
}