NativeUint8Array.java revision 1036:f0b5e3900a10
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; 29import java.lang.invoke.MethodHandle; 30import java.lang.invoke.MethodHandles; 31import java.nio.ByteBuffer; 32import jdk.nashorn.internal.objects.annotations.Attribute; 33import jdk.nashorn.internal.objects.annotations.Constructor; 34import jdk.nashorn.internal.objects.annotations.Function; 35import jdk.nashorn.internal.objects.annotations.Property; 36import jdk.nashorn.internal.objects.annotations.ScriptClass; 37import jdk.nashorn.internal.objects.annotations.Where; 38import jdk.nashorn.internal.runtime.JSType; 39import jdk.nashorn.internal.runtime.PropertyMap; 40import jdk.nashorn.internal.runtime.ScriptObject; 41import jdk.nashorn.internal.runtime.arrays.ArrayData; 42import jdk.nashorn.internal.runtime.arrays.TypedArrayData; 43 44/** 45 * Uint8 array for TypedArray extension 46 */ 47@ScriptClass("Uint8Array") 48public final class NativeUint8Array extends ArrayBufferView { 49 50 /** 51 * The size in bytes of each element in the array. 52 */ 53 @Property(attributes = Attribute.NOT_ENUMERABLE | Attribute.NOT_WRITABLE | Attribute.NOT_CONFIGURABLE, where = Where.CONSTRUCTOR) 54 public static final int BYTES_PER_ELEMENT = 1; 55 56 // initialized by nasgen 57 @SuppressWarnings("unused") 58 private static PropertyMap $nasgenmap$; 59 60 private static final Factory FACTORY = new Factory(BYTES_PER_ELEMENT) { 61 @Override 62 public ArrayBufferView construct(final NativeArrayBuffer buffer, final int byteOffset, final int length) { 63 return new NativeUint8Array(buffer, byteOffset, length); 64 } 65 66 @Override 67 public Uint8ArrayData createArrayData(final ByteBuffer nb, final int start, final int end) { 68 return new Uint8ArrayData(nb, start, end); 69 } 70 71 @Override 72 public String getClassName() { 73 return "Uint8Array"; 74 } 75 }; 76 77 private static final class Uint8ArrayData extends TypedArrayData<ByteBuffer> { 78 79 private static final MethodHandle GET_ELEM = specialCall(MethodHandles.lookup(), Uint8ArrayData.class, "getElem", int.class, int.class).methodHandle(); 80 private static final MethodHandle SET_ELEM = specialCall(MethodHandles.lookup(), Uint8ArrayData.class, "setElem", void.class, int.class, int.class).methodHandle(); 81 82 private Uint8ArrayData(final ByteBuffer nb, final int start, final int end) { 83 super(((ByteBuffer)nb.position(start).limit(end)).slice(), end - start); 84 } 85 86 @Override 87 protected MethodHandle getGetElem() { 88 return GET_ELEM; 89 } 90 91 @Override 92 protected MethodHandle getSetElem() { 93 return SET_ELEM; 94 } 95 96 private int getElem(final int index) { 97 try { 98 return nb.get(index) & 0xff; 99 } catch (final IndexOutOfBoundsException e) { 100 throw new ClassCastException(); //force relink - this works for unoptimistic too 101 } 102 } 103 104 private void setElem(final int index, final int elem) { 105 try { 106 nb.put(index, (byte)elem); 107 } catch (final IndexOutOfBoundsException e) { 108 //swallow valid array indexes. it's ok. 109 if (index < 0) { 110 throw new ClassCastException(); 111 } 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 int getInt(final int index) { 127 return getElem(index); 128 } 129 130 @Override 131 public long getLong(final int index) { 132 return getInt(index); 133 } 134 135 @Override 136 public double getDouble(final int index) { 137 return getInt(index); 138 } 139 140 @Override 141 public Object getObject(final int index) { 142 return getInt(index); 143 } 144 145 @Override 146 public ArrayData set(final int index, final Object value, final boolean strict) { 147 return set(index, JSType.toInt32(value), strict); 148 } 149 150 @Override 151 public ArrayData set(final int index, final int value, final boolean strict) { 152 setElem(index, value); 153 return this; 154 } 155 156 @Override 157 public ArrayData set(final int index, final long value, final boolean strict) { 158 return set(index, (int)value, strict); 159 } 160 161 @Override 162 public ArrayData set(final int index, final double value, final boolean strict) { 163 return set(index, (int)value, strict); 164 } 165 166 } 167 168 /** 169 * Constructor 170 * 171 * @param newObj is this typed array instantiated with the new operator 172 * @param self self reference 173 * @param args args 174 * 175 * @return new typed array 176 */ 177 @Constructor(arity = 1) 178 public static NativeUint8Array constructor(final boolean newObj, final Object self, final Object... args) { 179 return (NativeUint8Array)constructorImpl(newObj, args, FACTORY); 180 } 181 182 NativeUint8Array(final NativeArrayBuffer buffer, final int byteOffset, final int length) { 183 super(buffer, byteOffset, length); 184 } 185 186 @Override 187 protected Factory factory() { 188 return FACTORY; 189 } 190 191 /** 192 * Set values 193 * @param self self reference 194 * @param array multiple values of array's type to set 195 * @param offset optional start index, interpreted 0 if undefined 196 * @return undefined 197 */ 198 @Function(attributes = Attribute.NOT_ENUMERABLE) 199 protected static Object set(final Object self, final Object array, final Object offset) { 200 return ArrayBufferView.setImpl(self, array, offset); 201 } 202 203 /** 204 * Returns a new TypedArray view of the ArrayBuffer store for this TypedArray, 205 * referencing the elements at begin, inclusive, up to end, exclusive. If either 206 * begin or end is negative, it refers to an index from the end of the array, 207 * as opposed to from the beginning. 208 * <p> 209 * If end is unspecified, the subarray contains all elements from begin to the end 210 * of the TypedArray. The range specified by the begin and end values is clamped to 211 * the valid index range for the current array. If the computed length of the new 212 * TypedArray would be negative, it is clamped to zero. 213 * <p> 214 * The returned TypedArray will be of the same type as the array on which this 215 * method is invoked. 216 * 217 * @param self self reference 218 * @param begin begin position 219 * @param end end position 220 * 221 * @return sub array 222 */ 223 @Function(attributes = Attribute.NOT_ENUMERABLE) 224 protected static NativeUint8Array subarray(final Object self, final Object begin, final Object end) { 225 return (NativeUint8Array)ArrayBufferView.subarrayImpl(self, begin, end); 226 } 227 228 @Override 229 protected ScriptObject getPrototype(final Global global) { 230 return global.getUint8ArrayPrototype(); 231 } 232} 233