1 /*
   2  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.internal.runtime.arrays;
  27 
  28 import java.util.NoSuchElementException;
  29 import jdk.nashorn.internal.runtime.JSType;
  30 import jdk.nashorn.internal.runtime.ScriptObject;
  31 
  32 /**
  33  * Iterator over a map
  34  */
  35 class MapIterator extends ArrayLikeIterator<Object> {
  36 
  37     protected final ScriptObject obj;
  38     private final long length;
  39 
  40     MapIterator(final ScriptObject obj, final boolean includeUndefined) {
  41         super(includeUndefined);
  42         this.obj    = obj;
  43         this.length = JSType.toUint32(obj.getLength());
  44         this.index  = 0;
  45     }
  46 
  47     protected boolean indexInArray() {
  48         return index < length;
  49     }
  50 
  51     @Override
  52     public int getLength() {
  53         return (int) length;
  54     }
  55 
  56     @Override
  57     public boolean hasNext() {
  58         if (length == 0L) {
  59             return false; //return empty string if toUint32(length) == 0
  60         }
  61 
  62         while (indexInArray()) {
  63             if (obj.has(index) || includeUndefined) {
  64                 break;
  65             }
  66             bumpIndex();
  67         }
  68 
  69         return indexInArray();
  70     }
  71 
  72     @Override
  73     public Object next() {
  74         if (indexInArray()) {
  75             return obj.get(bumpIndex());
  76         }
  77 
  78         throw new NoSuchElementException();
  79     }
  80 }