ArrayIterator.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.utility.iterators;

import java.util.Iterator;
import java.util.NoSuchElementException;

import org.eclipse.persistence.tools.workbench.utility.ClassTools;
import org.eclipse.persistence.tools.workbench.utility.CollectionTools;


/**
 * An <code>ArrayIterator</code> provides an <code>Iterator</code>
 * for an array of objects.
 */
public class ArrayIterator
    implements Iterator
{
    Object[] array;    // private-protected
    int nextIndex;        // private-protected
    private int maxIndex;

    /**
     * Construct an iterator for the specified array.
     */
    public ArrayIterator(Object[] array) {
        this(array, 0, array.length);
    }

    /**
     * Construct an iterator for the specified array,
     * starting at the specified start index and continuing for
     * the specified length.
     */
    public ArrayIterator(Object[] array, int start, int length) {
        if ((start < 0) || (start > array.length)) {
            throw new IllegalArgumentException("start: " + start);
        }
        if ((length < 0) || (length > array.length - start)) {
            throw new IllegalArgumentException("length: " + length);
        }
        this.array = array;
        this.nextIndex = start;
        this.maxIndex = start + length;
    }

    /**
     * @see java.util.Iterator#hasNext()
     */
    public boolean hasNext() {
        return this.nextIndex < this.maxIndex;
    }

    /**
     * @see java.util.Iterator#next()
     */
    public Object next() {
        if (this.hasNext()) {
            return this.array[this.nextIndex++];
        }
        throw new NoSuchElementException();
    }

    /**
     * @see java.util.Iterator#remove()
     */
    public void remove() {
        throw new UnsupportedOperationException();
    }

    /**
     * @see java.lang.Object#toString()
     */
    public String toString() {
        return ClassTools.shortClassNameForObject(this) + '(' + CollectionTools.list(this.array) + ')';
    }

}