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.Iterator; 29 import jdk.nashorn.internal.runtime.JSType; 30 import jdk.nashorn.internal.runtime.ScriptObject; 31 32 /** 33 * Superclass for array iterators 34 * TODO: rewrite these 35 * 36 * @param <T> element type 37 */ 38 abstract public class ArrayLikeIterator<T> implements Iterator<T> { 39 40 /** current element index in iteration */ 41 protected long index; 42 43 /** should undefined elements be included in the iteration? */ 44 protected final boolean includeUndefined; 45 46 /** 47 * Constructor 48 * 49 * @param includeUndefined should undefined elements be included in the iteration? 50 */ 51 protected ArrayLikeIterator(final boolean includeUndefined) { 52 this.includeUndefined = includeUndefined; 53 this.index = 0; 54 } 55 56 /** 57 * Is this a reverse order iteration? 58 * @return true if reverse 59 */ 60 public boolean isReverse() { 61 return false; 62 } 63 64 /** 65 * Go the the next valid element index of the iterator 66 * @return next index 67 */ 68 protected long bumpIndex() { 69 return index++; 70 } 71 72 /** 73 * Return the next valid element index of the iterator 74 * @return next index 75 */ 76 public long nextIndex() { 77 return index; 78 } 79 80 @Override 81 public void remove() { 82 throw new UnsupportedOperationException("remove"); 83 } 84 85 /** 86 * Get the length of the iteration 87 * @return length 88 */ 89 public abstract long getLength(); 90 91 /** 92 * ArrayLikeIterator factory 93 * 94 * @param object object over which to do element iteration 95 * @return iterator 96 */ 97 public static ArrayLikeIterator<Object> arrayLikeIterator(final Object object) { 98 return arrayLikeIterator(object, false); 99 } 100 101 /** 102 * ArrayLikeIterator factory (reverse order) 103 * @param object object over which to do reverse element iteration 104 * @return iterator 105 */ 106 public static ArrayLikeIterator<Object> reverseArrayLikeIterator(final Object object) { 107 return reverseArrayLikeIterator(object, false); 108 } 109 110 /** 111 * ArrayLikeIterator factory 112 * @param object object over which to do reverse element iteration 113 * @param includeUndefined should undefined elements be included in the iteration 114 * @return iterator 115 */ 116 public static ArrayLikeIterator<Object> arrayLikeIterator(final Object object, final boolean includeUndefined) { 117 Object obj = object; 118 119 if (ScriptObject.isArray(obj)) { 120 return new ArrayIterator((ScriptObject) obj, includeUndefined); 121 } 122 123 obj = JSType.toScriptObject(obj); 124 if (obj instanceof ScriptObject) { 125 return new MapIterator((ScriptObject)obj, includeUndefined); 126 } 127 128 return new EmptyArrayLikeIterator(); 129 } 130 131 /** 132 * ArrayLikeIterator factory (reverse order) 133 * @param object object over which to do reverse element iteration 134 * @param includeUndefined should undefined elements be included in the iteration 135 * @return iterator 136 */ 137 public static ArrayLikeIterator<Object> reverseArrayLikeIterator(final Object object, final boolean includeUndefined) { 138 Object obj = object; 139 140 if (ScriptObject.isArray(obj)) { 141 return new ReverseArrayIterator((ScriptObject) obj, includeUndefined); 142 } 143 144 obj = JSType.toScriptObject(obj); 145 if (obj instanceof ScriptObject) { 146 return new ReverseMapIterator((ScriptObject)obj, includeUndefined); 147 } 148 149 assert !obj.getClass().isArray(); 150 151 return new EmptyArrayLikeIterator(); 152 } 153 154 } --- EOF ---