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 static jdk.nashorn.internal.codegen.CompilerConstants.staticCall; 30import static jdk.nashorn.internal.lookup.Lookup.MH; 31 32import java.lang.invoke.MethodHandle; 33import java.lang.invoke.MethodHandles; 34import java.nio.ByteBuffer; 35import jdk.nashorn.internal.objects.annotations.Attribute; 36import jdk.nashorn.internal.objects.annotations.Constructor; 37import jdk.nashorn.internal.objects.annotations.Function; 38import jdk.nashorn.internal.objects.annotations.Property; 39import jdk.nashorn.internal.objects.annotations.ScriptClass; 40import jdk.nashorn.internal.objects.annotations.Where; 41import jdk.nashorn.internal.runtime.JSType; 42import jdk.nashorn.internal.runtime.PropertyMap; 43import jdk.nashorn.internal.runtime.ScriptObject; 44import jdk.nashorn.internal.runtime.arrays.ArrayData; 45import jdk.nashorn.internal.runtime.arrays.TypedArrayData; 46 47/** 48 * Uint8 clamped array for TypedArray extension 49 */ 50@ScriptClass("Uint8ClampedArray") 51public final class NativeUint8ClampedArray extends ArrayBufferView { 52 /** 53 * The size in bytes of each element in the array. 54 */ 55 @Property(attributes = Attribute.NOT_ENUMERABLE | Attribute.NOT_WRITABLE | Attribute.NOT_CONFIGURABLE, where = Where.CONSTRUCTOR) 56 public static final int BYTES_PER_ELEMENT = 1; 57 58 // initialized by nasgen 59 @SuppressWarnings("unused") 60 private static PropertyMap $nasgenmap$; 61 62 private static final Factory FACTORY = new Factory(BYTES_PER_ELEMENT) { 63 @Override 64 public ArrayBufferView construct(final NativeArrayBuffer buffer, final int byteOffset, final int length) { 65 return new NativeUint8ClampedArray(buffer, byteOffset, length); 66 } 67 68 @Override 69 public Uint8ClampedArrayData createArrayData(final ByteBuffer nb, final int start, final int end) { 70 return new Uint8ClampedArrayData(nb, start, end); 71 } 72 73 @Override 74 public String getClassName() { 75 return "Uint8ClampedArray"; 76 } 77 }; 78 79 private static final class Uint8ClampedArrayData extends TypedArrayData<ByteBuffer> { 80 81 private static final MethodHandle GET_ELEM = specialCall(MethodHandles.lookup(), Uint8ClampedArrayData.class, "getElem", int.class, int.class).methodHandle(); 82 private static final MethodHandle SET_ELEM = specialCall(MethodHandles.lookup(), Uint8ClampedArrayData.class, "setElem", void.class, int.class, int.class).methodHandle(); 83 private static final MethodHandle RINT_D = staticCall(MethodHandles.lookup(), Uint8ClampedArrayData.class, "rint", double.class, double.class).methodHandle(); 84 private static final MethodHandle RINT_O = staticCall(MethodHandles.lookup(), Uint8ClampedArrayData.class, "rint", Object.class, Object.class).methodHandle(); 85 86 private Uint8ClampedArrayData(final ByteBuffer nb, final int start, final int end) { 87 super((nb.position(start).limit(end)).slice(), end - start); 88 } 89 90 @Override 91 protected MethodHandle getGetElem() { 92 return GET_ELEM; 93 } 94 95 @Override 96 protected MethodHandle getSetElem() { 97 return SET_ELEM; 98 } 99 100 @Override 101 public Class<?> getElementType() { 102 return int.class; 103 } 104 105 @Override 106 public Class<?> getBoxedElementType() { 107 return int.class; 108 } 109 110 private int getElem(final int index) { 111 try { 112 return nb.get(index) & 0xff; 113 } catch (final IndexOutOfBoundsException e) { 114 throw new ClassCastException(); //force relink - this works for unoptimistic too 115 } 116 } 117 118 @Override 119 public MethodHandle getElementSetter(final Class<?> elementType) { 120 final MethodHandle setter = super.getElementSetter(elementType); //getContinuousElementSetter(getClass(), setElem(), elementType); 121 if (setter != null) { 122 if (elementType == Object.class) { 123 return MH.filterArguments(setter, 2, RINT_O); 124 } else if (elementType == double.class) { 125 return MH.filterArguments(setter, 2, RINT_D); 126 } 127 } 128 return setter; 129 } 130 131 private void setElem(final int index, final int elem) { 132 try { 133 if (index < nb.limit()) { 134 final byte clamped; 135 if ((elem & 0xffff_ff00) == 0) { 136 clamped = (byte) elem; 137 } else { 138 clamped = elem < 0 ? 0 : (byte) 0xff; 139 } 140 nb.put(index, clamped); 141 } 142 } catch (final IndexOutOfBoundsException e) { 143 throw new ClassCastException(); 144 } 145 } 146 147 @Override 148 public boolean isClamped() { 149 return true; 150 } 151 152 @Override 153 public boolean isUnsigned() { 154 return true; 155 } 156 157 @Override 158 public int getInt(final int index) { 159 return getElem(index); 160 } 161 162 @Override 163 public int getIntOptimistic(final int index, final int programPoint) { 164 return getElem(index); 165 } 166 167 @Override 168 public double getDouble(final int index) { 169 return getInt(index); 170 } 171 172 @Override 173 public double getDoubleOptimistic(final int index, final int programPoint) { 174 return getElem(index); 175 } 176 177 @Override 178 public Object getObject(final int index) { 179 return getInt(index); 180 } 181 182 @Override 183 public ArrayData set(final int index, final Object value, final boolean strict) { 184 return set(index, JSType.toNumber(value), strict); 185 } 186 187 @Override 188 public ArrayData set(final int index, final int value, final boolean strict) { 189 setElem(index, value); 190 return this; 191 } 192 193 @Override 194 public ArrayData set(final int index, final double value, final boolean strict) { 195 return set(index, (int) rint(value), strict); 196 } 197 198 private static double rint(final double rint) { 199 return (int)Math.rint(rint); 200 } 201 202 @SuppressWarnings("unused") 203 private static Object rint(final Object rint) { 204 return rint(JSType.toNumber(rint)); 205 } 206 207 } 208 209 /** 210 * Constructor 211 * 212 * @param newObj is this typed array instantiated with the new operator 213 * @param self self reference 214 * @param args args 215 * 216 * @return new typed array 217 */ 218 @Constructor(arity = 1) 219 public static NativeUint8ClampedArray constructor(final boolean newObj, final Object self, final Object... args) { 220 return (NativeUint8ClampedArray)constructorImpl(newObj, args, FACTORY); 221 } 222 223 NativeUint8ClampedArray(final NativeArrayBuffer buffer, final int byteOffset, final int length) { 224 super(buffer, byteOffset, length); 225 } 226 227 @Override 228 protected Factory factory() { 229 return FACTORY; 230 } 231 232 /** 233 * Set values 234 * @param self self reference 235 * @param array multiple values of array's type to set 236 * @param offset optional start index, interpreted 0 if undefined 237 * @return undefined 238 */ 239 @Function(attributes = Attribute.NOT_ENUMERABLE) 240 protected static Object set(final Object self, final Object array, final Object offset) { 241 return ArrayBufferView.setImpl(self, array, offset); 242 } 243 244 /** 245 * Returns a new TypedArray view of the ArrayBuffer store for this TypedArray, 246 * referencing the elements at begin, inclusive, up to end, exclusive. If either 247 * begin or end is negative, it refers to an index from the end of the array, 248 * as opposed to from the beginning. 249 * <p> 250 * If end is unspecified, the subarray contains all elements from begin to the end 251 * of the TypedArray. The range specified by the begin and end values is clamped to 252 * the valid index range for the current array. If the computed length of the new 253 * TypedArray would be negative, it is clamped to zero. 254 * <p> 255 * The returned TypedArray will be of the same type as the array on which this 256 * method is invoked. 257 * 258 * @param self self reference 259 * @param begin begin position 260 * @param end end position 261 * 262 * @return sub array 263 */ 264 @Function(attributes = Attribute.NOT_ENUMERABLE) 265 protected static NativeUint8ClampedArray subarray(final Object self, final Object begin, final Object end) { 266 return (NativeUint8ClampedArray)ArrayBufferView.subarrayImpl(self, begin, end); 267 } 268 269 /** 270 * ECMA 6 22.2.3.30 %TypedArray%.prototype [ @@iterator ] ( ) 271 * 272 * @param self the self reference 273 * @return an iterator over the array's values 274 */ 275 @Function(attributes = Attribute.NOT_ENUMERABLE, name = "@@iterator") 276 public static Object getIterator(final Object self) { 277 return ArrayIterator.newArrayValueIterator(self); 278 } 279 280 @Override 281 protected ScriptObject getPrototype(final Global global) { 282 return global.getUint8ClampedArrayPrototype(); 283 } 284} 285