/* * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved. * * 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 Sun Microsystems 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. */ public class DataStructure {    //create an array    private final static int SIZE = 15;    private int[] arrayOfInts = new int[SIZE];        public DataStructure() {        //fill the array with ascending integer values        for (int i = 0; i < SIZE; i++) {            arrayOfInts[i] = i;        }    }        public void printEven() {        //print out values of even indices of the array        InnerEvenIterator iterator = this.new InnerEvenIterator();        while (iterator.hasNext()) {            System.out.println(iterator.getNext() + " ");        }    }    //inner class implements the Iterator pattern    private class InnerEvenIterator {        //start stepping through the array from the beginning        private int next = 0;                public boolean hasNext() {            //check if a current element is the last in the array            return (next <= SIZE - 1);        }                public int getNext() {            //record a value of an even index of the array            int retValue = arrayOfInts[next];            //get the next even element            next += 2;            return retValue;        }    }        public static void main(String s[]) {        //fill the array with integer values and print out only values of even indices        DataStructure ds = new DataStructure();        ds.printEven();    }}