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/*
 * Copyright (c) 2010 ANDRE S?bastien (divxdede).  All rights reserved.
 * IteratorEnumeration.java is a part of this Commons library
 * ====================================================================
 *
 * Commons library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the License,
 * or any later version.
 *
 * This is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see .
 */
package org.divxdede.collection;

import  java.util.*;

/**
 * Iterator based on an {@link Enumeration}.

 * This class is designed to be used with API that requires the new {@link Iterator}
 * and you need to provide one from an {@link Enumeration}
 *
 * @author Andr? S?bastien - INFASS Syst?mes (http://www.infass.com)
 */
public class IteratorEnumeration implements Iterator {

    private Enumeration enumeration = null;

    /** Constructor
     */
    public IteratorEnumeration(Enumeration enumeration) {
        this.enumeration = enumeration;
    }

    /**
     * Returns true if the iteration has more elements. (In other
     * words, returns true if next would return an element
     * rather than throwing an exception.)
     *
     * @return true if the iterator has more elements.
     */
    public boolean hasNext() {
        if( this.enumeration == null ) return false;
        return this.enumeration.hasMoreElements();
    }
    
    /**
     * Returns the next element in the iteration.
     *
     * @return the next element in the iteration.
     * @exception NoSuchElementException iteration has no more elements.
     */
    public E next() {
        if( this.enumeration == null ) throw new NoSuchElementException();
        return enumeration.nextElement();
    }
    
    /**
     *
     * Removes from the underlying collection the last element returned by the
     * iterator (optional operation).  This method can be called only once per
     * call to next.  The behavior of an iterator is unspecified if
     * the underlying collection is modified while the iteration is in
     * progress in any way other than by calling this method.
     *
     * @exception UnsupportedOperationException if the remove
     *		  operation is not supported by this Iterator.

     * @exception IllegalStateException if the next method has not
     *		  yet been called, or the remove method has already
     *		  been called after the last call to the next
     *		  method.
     */
     public void remove() {
         throw new UnsupportedOperationException();
     }
}