PrefetchIteratorTest.java

/* ==========================================
 * JGraphT : a free Java graph-theory library
 * ==========================================
 *
 * Project Info:  http://jgrapht.sourceforge.net/
 * Project Creator:  Barak Naveh (http://sourceforge.net/users/barak_naveh)
 *
 * (C) Copyright 2003-2008, by Barak Naveh and Contributors.
 *
 * This program and the accompanying materials are dual-licensed under
 * either
 *
 * (a) the terms of the GNU Lesser General Public License version 2.1
 * as published by the Free Software Foundation, or (at your option) any
 * later version.
 *
 * or (per the licensee's choosing)
 *
 * (b) the terms of the Eclipse Public License v1.0 as published by
 * the Eclipse Foundation.
 */
/* -----------------
 * PrefetchIteratorTest.java
 * -----------------
 * (C) Copyright 2005-2008, by Assaf Lehr and Contributors.
 *
 * Original Author:  Assaf Lehr
 * Contributor(s):   -
 *
 * $Id$
 *
 * Changes
 * -------
 */
package org.jgrapht.util;

import java.util.*;

import junit.framework.*;


public class PrefetchIteratorTest
    extends TestCase
{
    //~ Methods ----------------------------------------------------------------

    public void testIteratorInterface()
    {
        Iterator iterator = new IterateFrom1To99();
        for (int i = 1; i < 100; i++) {
            assertEquals(true, iterator.hasNext());
            assertEquals(i, iterator.next());
        }
        assertEquals(false, iterator.hasNext());
        Exception exceptionThrown = null;
        try {
            iterator.next();
        } catch (Exception e) {
            exceptionThrown = e;
        }
        assertTrue(exceptionThrown instanceof NoSuchElementException);
    }

    public void testEnumInterface()
    {
        Enumeration enumuration = new IterateFrom1To99();
        for (int i = 1; i < 100; i++) {
            assertEquals(true, enumuration.hasMoreElements());
            assertEquals(i, enumuration.nextElement());
        }
        assertEquals(false, enumuration.hasMoreElements());
        Exception exceptionThrown = null;
        try {
            enumuration.nextElement();
        } catch (Exception e) {
            exceptionThrown = e;
        }
        assertTrue(exceptionThrown instanceof NoSuchElementException);
    }

    //~ Inner Classes ----------------------------------------------------------

    // This test class supplies enumeration of integer from 1 till 100.
    public static class IterateFrom1To99
        implements Enumeration,
            Iterator
    {
        private int counter = 0;
        private PrefetchIterator nextSupplier;

        public IterateFrom1To99()
        {
            nextSupplier =
                new PrefetchIterator<Integer>(
                    new PrefetchIterator.NextElementFunctor<Integer>() {
                        public Integer nextElement()
                            throws NoSuchElementException
                        {
                            counter++;
                            if (counter >= 100) {
                                throw new NoSuchElementException();
                            } else {
                                return new Integer(counter);
                            }
                        }
                    });
        }

        // forwarding to nextSupplier and return its returned value
        public boolean hasMoreElements()
        {
            return this.nextSupplier.hasMoreElements();
        }

        // forwarding to nextSupplier and return its returned value
        public Object nextElement()
        {
            return this.nextSupplier.nextElement();
        }

        public Object next()
        {
            return this.nextSupplier.next();
        }

        public boolean hasNext()
        {
            return this.nextSupplier.hasNext();
        }

        public void remove()
        {
            this.nextSupplier.remove();
        }
    }
}

// End PrefetchIteratorTest.java