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 26 package jdk.nashorn.internal.runtime.arrays; 27 28 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED; 29 import java.lang.reflect.Array; 30 import jdk.nashorn.internal.runtime.BitVector; 31 import jdk.nashorn.internal.runtime.UnwarrantedOptimismException; 32 33 /** 34 * This filter handles the presence of undefined array elements. 35 */ 36 final 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 void shiftLeft(final int by) { 81 super.shiftLeft(by); 82 undefined.shiftLeft(by, length()); 83 } 84 85 @Override 86 public ArrayData shiftRight(final int by) { 87 super.shiftRight(by); 88 undefined.shiftRight(by, length()); 89 return this; 90 } 91 92 @Override 93 public ArrayData ensure(final long safeIndex) { 94 if (safeIndex >= SparseArrayData.MAX_DENSE_LENGTH && safeIndex >= length()) { 95 return new SparseArrayData(this, safeIndex + 1); 96 } 97 98 super.ensure(safeIndex); 99 undefined.resize(length()); 100 101 return this; 102 } 103 104 @Override 105 public ArrayData shrink(final long newLength) { 106 super.shrink(newLength); 107 undefined.resize(length()); 108 return this; 109 } 110 111 @Override 112 public ArrayData set(final int index, final Object value, final boolean strict) { 113 undefined.clear(index); 114 115 if (value == UNDEFINED) { 116 undefined.set(index); 117 return this; 118 } 119 120 return super.set(index, value, strict); 121 } 122 123 @Override 124 public ArrayData set(final int index, final int value, final boolean strict) { 125 undefined.clear(index); 126 127 return super.set(index, value, strict); 128 } 129 130 @Override 131 public ArrayData set(final int index, final double value, final boolean strict) { 132 undefined.clear(index); 133 134 return super.set(index, value, strict); 135 } 136 137 @Override 138 public int getInt(final int index) { 139 if (undefined.isSet(index)) { 140 return 0; 141 } 142 143 return super.getInt(index); 144 } 145 146 @Override 147 public int getIntOptimistic(final int index, final int programPoint) { 148 if (undefined.isSet(index)) { 149 throw new UnwarrantedOptimismException(UNDEFINED, programPoint); 150 } 151 152 return super.getIntOptimistic(index, programPoint); 153 } 154 155 @Override 156 public double getDouble(final int index) { 157 if (undefined.isSet(index)) { 158 return Double.NaN; 159 } 160 161 return super.getDouble(index); 162 } 163 164 @Override 165 public double getDoubleOptimistic(final int index, final int programPoint) { 166 if (undefined.isSet(index)) { 167 throw new UnwarrantedOptimismException(UNDEFINED, programPoint); 168 } 169 170 return super.getDoubleOptimistic(index, programPoint); 171 } 172 173 @Override 174 public Object getObject(final int index) { 175 if (undefined.isSet(index)) { 176 return UNDEFINED; 177 } 178 179 return super.getObject(index); 180 } 181 182 @Override 183 public ArrayData delete(final int index) { 184 undefined.clear(index); 185 186 return super.delete(index); 187 } 188 189 @Override 190 public Object pop() { 191 final long index = length() - 1; 192 193 if (super.has((int)index)) { 194 final boolean isUndefined = undefined.isSet(index); 195 final Object value = super.pop(); 196 197 return isUndefined ? UNDEFINED : value; 198 } 199 200 return super.pop(); 201 } 202 203 @Override 204 public ArrayData slice(final long from, final long to) { 205 final ArrayData newArray = underlying.slice(from, to); 206 final UndefinedArrayFilter newFilter = new UndefinedArrayFilter(newArray); 207 newFilter.getUndefined().copy(undefined); 208 newFilter.getUndefined().shiftLeft(from, newFilter.length()); 209 210 return newFilter; 211 } 212 213 private BitVector getUndefined() { 214 return undefined; 215 } 216 }