IteratorEnumeration.java

/*
 *  Copyright 1999-2004 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package com.uwyn.rife.tools;

import java.util.Enumeration;
import java.util.Iterator;

/**
 * Adapter to make an {@link Iterator Iterator} instance appear to be
 * an {@link Enumeration Enumeration} instance.
 *
 * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
 * @version $Revision: 3308 $ $Date: 2004/05/03 10:23:38 $
 * @since Commons Collections 1.0
 */
public class IteratorEnumeration implements Enumeration
{

    /**
     * The iterator being decorated.
     */
    private Iterator iterator;

    /**
     * Constructs a new <code>IteratorEnumeration</code> that will not
     * function until {@link #setIterator(Iterator) setIterator} is
     * invoked.
     */
    public IteratorEnumeration()
    {
        super();
    }

    /**
     * Constructs a new <code>IteratorEnumeration</code> that will use
     * the given iterator.
     *
     * @param iterator the iterator to use
     */
    public IteratorEnumeration(Iterator iterator)
    {
        super();
        this.iterator = iterator;
    }

    // Iterator interface
    //-------------------------------------------------------------------------

    /**
     * Returns true if the underlying iterator has more elements.
     *
     * @return true if the underlying iterator has more elements
     */
    public boolean hasMoreElements()
    {
        return iterator.hasNext();
    }

    /**
     * Returns the next element from the underlying iterator.
     *
     * @return the next element from the underlying iterator.
     * @throws java.util.NoSuchElementException
     *          if the underlying iterator has no
     *          more elements
     */
    public Object nextElement()
    {
        return iterator.next();
    }

    // Properties
    //-------------------------------------------------------------------------

    /**
     * Returns the underlying iterator.
     *
     * @return the underlying iterator
     */
    public Iterator getIterator()
    {
        return iterator;
    }

    /**
     * Sets the underlying iterator.
     *
     * @param iterator the new underlying iterator
     */
    public void setIterator(Iterator iterator)
    {
        this.iterator = iterator;
    }

}