/*

 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package jdk.nashorn.internal.runtime.arrays;

import jdk.nashorn.api.scripting.JSObject;

import jdk.nashorn.internal.runtime.JSType;

/**

 * Reverse iterator over a ScriptObjectMirror

 */

final class ReverseJSObjectIterator extends JSObjectIterator {

    ReverseJSObjectIterator(final JSObject obj, final boolean includeUndefined) {

        super(obj, includeUndefined);

        this.index = JSType.toUint32(obj.hasMember("length")? obj.getMember("length") : 0) - 1;

    }

    @Override

    public boolean isReverse() {

        return true;

    }

    @Override

    protected boolean indexInArray() {

        return index >= 0;

    }

    @Override

    protected long bumpIndex() {

        return index--;

    }

}