NativeUint8ClampedArray.java revision 1692:bb6cf30cf892
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 private static final MethodHandle CLAMP_LONG = staticCall(MethodHandles.lookup(), Uint8ClampedArrayData.class, "clampLong", long.class, long.class).methodHandle(); 86 87 private Uint8ClampedArrayData(final ByteBuffer nb, final int start, final int end) { 88 super((nb.position(start).limit(end)).slice(), end - start); 89 } 90 91 @Override 92 protected MethodHandle getGetElem() { 93 return GET_ELEM; 94 } 95 96 @Override 97 protected MethodHandle getSetElem() { 98 return SET_ELEM; 99 } 100 101 @Override 102 public Class<?> getElementType() { 103 return int.class; 104 } 105 106 @Override 107 public Class<?> getBoxedElementType() { 108 return int.class; 109 } 110 111 private int getElem(final int index) { 112 try { 113 return nb.get(index) & 0xff; 114 } catch (final IndexOutOfBoundsException e) { 115 throw new ClassCastException(); //force relink - this works for unoptimistic too 116 } 117 } 118 119 @Override 120 public MethodHandle getElementSetter(final Class<?> elementType) { 121 final MethodHandle setter = super.getElementSetter(elementType); //getContinuousElementSetter(getClass(), setElem(), elementType); 122 if (setter != null) { 123 if (elementType == Object.class) { 124 return MH.filterArguments(setter, 2, RINT_O); 125 } else if (elementType == double.class) { 126 return MH.filterArguments(setter, 2, RINT_D); 127 } else if (elementType == long.class) { 128 return MH.filterArguments(setter, 2, CLAMP_LONG); 129 } 130 } 131 return setter; 132 } 133 134 private void setElem(final int index, final int elem) { 135 try { 136 if (index < nb.limit()) { 137 final byte clamped; 138 if ((elem & 0xffff_ff00) == 0) { 139 clamped = (byte) elem; 140 } else { 141 clamped = elem < 0 ? 0 : (byte) 0xff; 142 } 143 nb.put(index, clamped); 144 } 145 } catch (final IndexOutOfBoundsException e) { 146 throw new ClassCastException(); 147 } 148 } 149 150 @Override 151 public boolean isClamped() { 152 return true; 153 } 154 155 @Override 156 public boolean isUnsigned() { 157 return true; 158 } 159 160 @Override 161 public int getInt(final int index) { 162 return getElem(index); 163 } 164 165 @Override 166 public int getIntOptimistic(final int index, final int programPoint) { 167 return getElem(index); 168 } 169 170 @Override 171 public double getDouble(final int index) { 172 return getInt(index); 173 } 174 175 @Override 176 public double getDoubleOptimistic(final int index, final int programPoint) { 177 return getElem(index); 178 } 179 180 @Override 181 public Object getObject(final int index) { 182 return getInt(index); 183 } 184 185 @Override 186 public ArrayData set(final int index, final Object value, final boolean strict) { 187 return set(index, JSType.toNumber(value), strict); 188 } 189 190 @Override 191 public ArrayData set(final int index, final int value, final boolean strict) { 192 setElem(index, value); 193 return this; 194 } 195 196 @Override 197 public ArrayData set(final int index, final double value, final boolean strict) { 198 return set(index, rint(value), strict); 199 } 200 201 private static double rint(final double rint) { 202 return (int)Math.rint(rint); 203 } 204 205 @SuppressWarnings("unused") 206 private static Object rint(final Object rint) { 207 return rint(JSType.toNumber(rint)); 208 } 209 210 @SuppressWarnings("unused") 211 private static long clampLong(final long l) { 212 if(l < 0L) { 213 return 0L; 214 } else if(l > 0xffL) { 215 return 0xffL; 216 } 217 return l; 218 } 219 } 220 221 /** 222 * Constructor 223 * 224 * @param newObj is this typed array instantiated with the new operator 225 * @param self self reference 226 * @param args args 227 * 228 * @return new typed array 229 */ 230 @Constructor(arity = 1) 231 public static NativeUint8ClampedArray constructor(final boolean newObj, final Object self, final Object... args) { 232 return (NativeUint8ClampedArray)constructorImpl(newObj, args, FACTORY); 233 } 234 235 NativeUint8ClampedArray(final NativeArrayBuffer buffer, final int byteOffset, final int length) { 236 super(buffer, byteOffset, length); 237 } 238 239 @Override 240 protected Factory factory() { 241 return FACTORY; 242 } 243 244 /** 245 * Set values 246 * @param self self reference 247 * @param array multiple values of array's type to set 248 * @param offset optional start index, interpreted 0 if undefined 249 * @return undefined 250 */ 251 @Function(attributes = Attribute.NOT_ENUMERABLE) 252 protected static Object set(final Object self, final Object array, final Object offset) { 253 return ArrayBufferView.setImpl(self, array, offset); 254 } 255 256 /** 257 * Returns a new TypedArray view of the ArrayBuffer store for this TypedArray, 258 * referencing the elements at begin, inclusive, up to end, exclusive. If either 259 * begin or end is negative, it refers to an index from the end of the array, 260 * as opposed to from the beginning. 261 * <p> 262 * If end is unspecified, the subarray contains all elements from begin to the end 263 * of the TypedArray. The range specified by the begin and end values is clamped to 264 * the valid index range for the current array. If the computed length of the new 265 * TypedArray would be negative, it is clamped to zero. 266 * <p> 267 * The returned TypedArray will be of the same type as the array on which this 268 * method is invoked. 269 * 270 * @param self self reference 271 * @param begin begin position 272 * @param end end position 273 * 274 * @return sub array 275 */ 276 @Function(attributes = Attribute.NOT_ENUMERABLE) 277 protected static NativeUint8ClampedArray subarray(final Object self, final Object begin, final Object end) { 278 return (NativeUint8ClampedArray)ArrayBufferView.subarrayImpl(self, begin, end); 279 } 280 281 @Override 282 protected ScriptObject getPrototype(final Global global) { 283 return global.getUint8ClampedArrayPrototype(); 284 } 285} 286