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.runtime.arrays; 27 28import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; 29import java.lang.reflect.Array; 30import jdk.nashorn.internal.runtime.BitVector; 31import jdk.nashorn.internal.runtime.UnwarrantedOptimismException; 32 33/** 34 * This filter handles the presence of undefined array elements. 35 */ 36final class UndefinedArrayFilter extends ArrayFilter { 37 /** Bit vector tracking undefined slots. */ 38 private final BitVector undefined; 39 40 UndefinedArrayFilter(final ArrayData underlying) { 41 super(underlying); 42 this.undefined = new BitVector(underlying.length()); 43 } 44 45 @Override 46 public ArrayData copy() { 47 final UndefinedArrayFilter copy = new UndefinedArrayFilter(underlying.copy()); 48 copy.getUndefined().copy(undefined); 49 return copy; 50 } 51 52 @Override 53 public Object[] asObjectArray() { 54 final Object[] value = super.asObjectArray(); 55 56 for (int i = 0; i < value.length; i++) { 57 if (undefined.isSet(i)) { 58 value[i] = UNDEFINED; 59 } 60 } 61 62 return value; 63 } 64 65 @Override 66 public Object asArrayOfType(final Class<?> componentType) { 67 final Object value = super.asArrayOfType(componentType); 68 final Object undefValue = convertUndefinedValue(componentType); 69 final int l = Array.getLength(value); 70 for (int i = 0; i < l; i++) { 71 if (undefined.isSet(i)) { 72 Array.set(value, i,undefValue); 73 } 74 } 75 76 return value; 77 } 78 79 @Override 80 public ArrayData shiftLeft(final int by) { 81 super.shiftLeft(by); 82 undefined.shiftLeft(by, length()); 83 return this; 84 } 85 86 @Override 87 public ArrayData shiftRight(final int by) { 88 super.shiftRight(by); 89 undefined.shiftRight(by, length()); 90 return this; 91 } 92 93 @Override 94 public ArrayData ensure(final long safeIndex) { 95 if (safeIndex >= SparseArrayData.MAX_DENSE_LENGTH && safeIndex >= length()) { 96 return new SparseArrayData(this, safeIndex + 1); 97 } 98 99 super.ensure(safeIndex); 100 undefined.resize(length()); 101 102 return this; 103 } 104 105 @Override 106 public ArrayData shrink(final long newLength) { 107 super.shrink(newLength); 108 undefined.resize(length()); 109 return this; 110 } 111 112 @Override 113 public ArrayData set(final int index, final Object value, final boolean strict) { 114 undefined.clear(index); 115 116 if (value == UNDEFINED) { 117 undefined.set(index); 118 return this; 119 } 120 121 return super.set(index, value, strict); 122 } 123 124 @Override 125 public ArrayData set(final int index, final int value, final boolean strict) { 126 undefined.clear(index); 127 128 return super.set(index, value, strict); 129 } 130 131 @Override 132 public ArrayData set(final int index, final double value, final boolean strict) { 133 undefined.clear(index); 134 135 return super.set(index, value, strict); 136 } 137 138 @Override 139 public int getInt(final int index) { 140 if (undefined.isSet(index)) { 141 return 0; 142 } 143 144 return super.getInt(index); 145 } 146 147 @Override 148 public int getIntOptimistic(final int index, final int programPoint) { 149 if (undefined.isSet(index)) { 150 throw new UnwarrantedOptimismException(UNDEFINED, programPoint); 151 } 152 153 return super.getIntOptimistic(index, programPoint); 154 } 155 156 @Override 157 public double getDouble(final int index) { 158 if (undefined.isSet(index)) { 159 return Double.NaN; 160 } 161 162 return super.getDouble(index); 163 } 164 165 @Override 166 public double getDoubleOptimistic(final int index, final int programPoint) { 167 if (undefined.isSet(index)) { 168 throw new UnwarrantedOptimismException(UNDEFINED, programPoint); 169 } 170 171 return super.getDoubleOptimistic(index, programPoint); 172 } 173 174 @Override 175 public Object getObject(final int index) { 176 if (undefined.isSet(index)) { 177 return UNDEFINED; 178 } 179 180 return super.getObject(index); 181 } 182 183 @Override 184 public ArrayData delete(final int index) { 185 undefined.clear(index); 186 187 return super.delete(index); 188 } 189 190 @Override 191 public Object pop() { 192 final long index = length() - 1; 193 194 if (super.has((int)index)) { 195 final boolean isUndefined = undefined.isSet(index); 196 final Object value = super.pop(); 197 198 return isUndefined ? UNDEFINED : value; 199 } 200 201 return super.pop(); 202 } 203 204 @Override 205 public ArrayData slice(final long from, final long to) { 206 final ArrayData newArray = underlying.slice(from, to); 207 final UndefinedArrayFilter newFilter = new UndefinedArrayFilter(newArray); 208 newFilter.getUndefined().copy(undefined); 209 newFilter.getUndefined().shiftLeft(from, newFilter.length()); 210 211 return newFilter; 212 } 213 214 private BitVector getUndefined() { 215 return undefined; 216 } 217} 218