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 java.util.List;
30 import jdk.nashorn.api.scripting.JSObject;
31 import jdk.nashorn.internal.runtime.JSType;
32 import jdk.nashorn.internal.runtime.ScriptObject;
33
34 /**
35 * Superclass for array iterators
36 * TODO: rewrite these
37 *
38 * @param <T> element type
39 */
40 abstract public class ArrayLikeIterator<T> implements Iterator<T> {
41
42 /** current element index in iteration */
43 protected long index;
44
45 /** should undefined elements be included in the iteration? */
46 protected final boolean includeUndefined;
47
48 /**
49 * Constructor
50 *
51 * @param includeUndefined should undefined elements be included in the iteration?
52 */
53 ArrayLikeIterator(final boolean includeUndefined) {
54 this.includeUndefined = includeUndefined;
55 this.index = 0;
56 }
57
58 /**
59 * Is this a reverse order iteration?
60 * @return true if reverse
61 */
62 public boolean isReverse() {
63 return false;
64 }
65
66 /**
67 * Go the the next valid element index of the iterator
68 * @return next index
69 */
70 protected long bumpIndex() {
71 return index++;
72 }
73
74 /**
75 * Return the next valid element index of the iterator
76 * @return next index
77 */
78 public long nextIndex() {
79 return index;
80 }
81
82 @Override
83 public void remove() {
84 throw new UnsupportedOperationException("remove");
85 }
86
87 /**
88 * Get the length of the iteration
89 * @return length
90 */
91 public abstract long getLength();
92
93 /**
94 * ArrayLikeIterator factory
95 *
96 * @param object object over which to do element iteration
97 * @return iterator
98 */
99 public static ArrayLikeIterator<Object> arrayLikeIterator(final Object object) {
100 return arrayLikeIterator(object, false);
101 }
102
103 /**
104 * ArrayLikeIterator factory (reverse order)
105 * @param object object over which to do reverse element iteration
106 * @return iterator
107 */
108 public static ArrayLikeIterator<Object> reverseArrayLikeIterator(final Object object) {
109 return reverseArrayLikeIterator(object, false);
110 }
111
112 /**
113 * ArrayLikeIterator factory
114 * @param object object over which to do reverse element iteration
115 * @param includeUndefined should undefined elements be included in the iteration
116 * @return iterator
117 */
118 public static ArrayLikeIterator<Object> arrayLikeIterator(final Object object, final boolean includeUndefined) {
119 Object obj = object;
120
121 if (ScriptObject.isArray(obj)) {
122 return new ScriptArrayIterator((ScriptObject) obj, includeUndefined);
123 }
124
125 obj = JSType.toScriptObject(obj);
126 if (obj instanceof ScriptObject) {
127 return new ScriptObjectIterator((ScriptObject)obj, includeUndefined);
128 }
129
130 if (obj instanceof JSObject) {
131 return new JSObjectIterator((JSObject)obj, includeUndefined);
132 }
133
134 if (obj instanceof List) {
135 return new JavaListIterator((List<?>)obj, includeUndefined);
136 }
137
138 if (obj != null && obj.getClass().isArray()) {
139 return new JavaArrayIterator(obj, includeUndefined);
140 }
141
142 return new EmptyArrayLikeIterator();
143 }
144
145 /**
146 * ArrayLikeIterator factory (reverse order)
147 * @param object object over which to do reverse element iteration
148 * @param includeUndefined should undefined elements be included in the iteration
149 * @return iterator
150 */
151 public static ArrayLikeIterator<Object> reverseArrayLikeIterator(final Object object, final boolean includeUndefined) {
152 Object obj = object;
153
154 if (ScriptObject.isArray(obj)) {
155 return new ReverseScriptArrayIterator((ScriptObject) obj, includeUndefined);
156 }
157
158 obj = JSType.toScriptObject(obj);
159 if (obj instanceof ScriptObject) {
160 return new ReverseScriptObjectIterator((ScriptObject)obj, includeUndefined);
161 }
162
163 if (obj instanceof JSObject) {
164 return new ReverseJSObjectIterator((JSObject)obj, includeUndefined);
165 }
166
167 if (obj instanceof List) {
168 return new ReverseJavaListIterator((List<?>)obj, includeUndefined);
169 }
170
171 if (obj != null && obj.getClass().isArray()) {
172 return new ReverseJavaArrayIterator(obj, includeUndefined);
173 }
174
175 return new EmptyArrayLikeIterator();
176 }
177
178 }