NativeUint16Array.java revision 1801:1272bfe44562 
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
26package jdk.nashorn.internal.objects;
27
28import static jdk.nashorn.internal.codegen.CompilerConstants.specialCall;
29
30import java.lang.invoke.MethodHandle;
31import java.lang.invoke.MethodHandles;
32import java.nio.ByteBuffer;
33import java.nio.CharBuffer;
34import jdk.nashorn.internal.objects.annotations.Attribute;
35import jdk.nashorn.internal.objects.annotations.Constructor;
36import jdk.nashorn.internal.objects.annotations.Function;
37import jdk.nashorn.internal.objects.annotations.Property;
38import jdk.nashorn.internal.objects.annotations.ScriptClass;
39import jdk.nashorn.internal.objects.annotations.Where;
40import jdk.nashorn.internal.runtime.JSType;
41import jdk.nashorn.internal.runtime.PropertyMap;
42import jdk.nashorn.internal.runtime.ScriptObject;
43import jdk.nashorn.internal.runtime.arrays.ArrayData;
44import jdk.nashorn.internal.runtime.arrays.TypedArrayData;
45
46/**
47 * Uint16 array for TypedArray extension
48 */
49@ScriptClass("Uint16Array")
50public final class NativeUint16Array extends ArrayBufferView {
51    /**
52     * The size in bytes of each element in the array.
53     */
54    @Property(attributes = Attribute.NOT_ENUMERABLE | Attribute.NOT_WRITABLE | Attribute.NOT_CONFIGURABLE, where = Where.CONSTRUCTOR)
55    public static final int BYTES_PER_ELEMENT = 2;
56
57    // initialized by nasgen
58    @SuppressWarnings("unused")
59    private static PropertyMap $nasgenmap$;
60
61    private static final Factory FACTORY = new Factory(BYTES_PER_ELEMENT) {
62        @Override
63        public ArrayBufferView construct(final NativeArrayBuffer buffer, final int byteOffset, final int length) {
64            return new NativeUint16Array(buffer, byteOffset, length);
65        }
66
67        @Override
68        public Uint16ArrayData createArrayData(final ByteBuffer nb, final int start, final int end) {
69            return new Uint16ArrayData(nb.asCharBuffer(), start, end);
70        }
71
72        @Override
73        public String getClassName() {
74            return "Uint16Array";
75        }
76    };
77
78    private static final class Uint16ArrayData extends TypedArrayData<CharBuffer> {
79
80        private static final MethodHandle GET_ELEM = specialCall(MethodHandles.lookup(), Uint16ArrayData.class, "getElem", int.class, int.class).methodHandle();
81        private static final MethodHandle SET_ELEM = specialCall(MethodHandles.lookup(), Uint16ArrayData.class, "setElem", void.class, int.class, int.class).methodHandle();
82
83        private Uint16ArrayData(final CharBuffer nb, final int start, final int end) {
84            super((nb.position(start).limit(end)).slice(), end - start);
85        }
86
87        @Override
88        protected MethodHandle getGetElem() {
89            return GET_ELEM;
90        }
91
92        @Override
93        protected MethodHandle getSetElem() {
94            return SET_ELEM;
95        }
96
97        private int getElem(final int index) {
98            try {
99                return nb.get(index);
100            } catch (final IndexOutOfBoundsException e) {
101                throw new ClassCastException(); //force relink - this works for unoptimistic too
102            }
103        }
104
105        private void setElem(final int index, final int elem) {
106            try {
107                if (index < nb.limit()) {
108                    nb.put(index, (char) elem);
109                }
110            } catch (final IndexOutOfBoundsException e) {
111                throw new ClassCastException();
112            }
113        }
114
115        @Override
116        public boolean isUnsigned() {
117            return true;
118        }
119
120        @Override
121        public Class<?> getElementType() {
122            return int.class;
123        }
124
125        @Override
126        public Class<?> getBoxedElementType() {
127            return Integer.class;
128        }
129
130        @Override
131        public int getInt(final int index) {
132            return getElem(index);
133        }
134
135        @Override
136        public int getIntOptimistic(final int index, final int programPoint) {
137            return getElem(index);
138        }
139
140        @Override
141        public double getDouble(final int index) {
142            return getInt(index);
143        }
144
145        @Override
146        public double getDoubleOptimistic(final int index, final int programPoint) {
147            return getElem(index);
148        }
149
150        @Override
151        public Object getObject(final int index) {
152            return getInt(index);
153        }
154
155        @Override
156        public ArrayData set(final int index, final Object value, final boolean strict) {
157            return set(index, JSType.toInt32(value), strict);
158        }
159
160        @Override
161        public ArrayData set(final int index, final int value, final boolean strict) {
162            setElem(index, value);
163            return this;
164        }
165
166        @Override
167        public ArrayData set(final int index, final double value, final boolean strict) {
168            return set(index, (int)value, strict);
169        }
170    }
171
172    /**
173     * Constructor
174     *
175     * @param newObj is this typed array instantiated with the new operator
176     * @param self   self reference
177     * @param args   args
178     *
179     * @return new typed array
180     */
181    @Constructor(arity = 1)
182    public static NativeUint16Array constructor(final boolean newObj, final Object self, final Object... args) {
183        return (NativeUint16Array)constructorImpl(newObj, args, FACTORY);
184    }
185
186    NativeUint16Array(final NativeArrayBuffer buffer, final int byteOffset, final int length) {
187        super(buffer, byteOffset, length);
188    }
189
190    @Override
191    protected Factory factory() {
192        return FACTORY;
193    }
194
195    /**
196     * Set values
197     * @param self   self reference
198     * @param array  multiple values of array's type to set
199     * @param offset optional start index, interpreted  0 if undefined
200     * @return undefined
201     */
202    @Function(attributes = Attribute.NOT_ENUMERABLE)
203    protected static Object set(final Object self, final Object array, final Object offset) {
204        return ArrayBufferView.setImpl(self, array, offset);
205    }
206
207    /**
208     * Returns a new TypedArray view of the ArrayBuffer store for this TypedArray,
209     * referencing the elements at begin, inclusive, up to end, exclusive. If either
210     * begin or end is negative, it refers to an index from the end of the array,
211     * as opposed to from the beginning.
212     * <p>
213     * If end is unspecified, the subarray contains all elements from begin to the end
214     * of the TypedArray. The range specified by the begin and end values is clamped to
215     * the valid index range for the current array. If the computed length of the new
216     * TypedArray would be negative, it is clamped to zero.
217     * <p>
218     * The returned TypedArray will be of the same type as the array on which this
219     * method is invoked.
220     *
221     * @param self self reference
222     * @param begin begin position
223     * @param end end position
224     *
225     * @return sub array
226     */
227    @Function(attributes = Attribute.NOT_ENUMERABLE)
228    protected static NativeUint16Array subarray(final Object self, final Object begin, final Object end) {
229        return (NativeUint16Array)ArrayBufferView.subarrayImpl(self, begin, end);
230    }
231
232    /**
233     * ECMA 6 22.2.3.30 %TypedArray%.prototype [ @@iterator ] ( )
234     *
235     * @param self the self reference
236     * @return an iterator over the array's values
237     */
238    @Function(attributes = Attribute.NOT_ENUMERABLE, name = "@@iterator")
239    public static Object getIterator(final Object self) {
240        return ArrayIterator.newArrayValueIterator(self);
241    }
242
243    @Override
244    protected ScriptObject getPrototype(final Global global) {
245        return global.getUint16ArrayPrototype();
246    }
247}
248