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25 
26 package jdk.nashorn.internal.runtime.arrays;
27 
28 import jdk.nashorn.internal.runtime.ScriptObject;
29 
30 /**
31  * Reverse iterator over a NativeArray
32  */
33 final class ReverseScriptArrayIterator extends ScriptArrayIterator {
34 
35     /**
36      * Constructor
37      * @param array array to iterate over
38      * @param includeUndefined should undefined elements be included in iteration
39      */
ReverseScriptArrayIterator(final ScriptObject array, final boolean includeUndefined)40     public ReverseScriptArrayIterator(final ScriptObject array, final boolean includeUndefined) {
41         super(array, includeUndefined);
42         this.index = array.getArray().length() - 1;
43     }
44 
45     @Override
isReverse()46     public boolean isReverse() {
47         return true;
48     }
49 
50     @Override
indexInArray()51     protected boolean indexInArray() {
52         return index >= 0;
53     }
54 
55     @Override
bumpIndex()56     protected long bumpIndex() {
57         return index--;
58     }
59 }
60