| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.nashorn.internal.runtime.arrays; |
| |
| import java.lang.reflect.Array; |
| import jdk.nashorn.internal.runtime.ScriptRuntime; |
| |
| /** |
| * This filter handles the deletion of array elements. |
| */ |
| final class DeletedRangeArrayFilter extends ArrayFilter { |
| /** Range (inclusive) tracking deletions */ |
| private long lo, hi; |
| |
| DeletedRangeArrayFilter(final ArrayData underlying, final long lo, final long hi) { |
| super(maybeSparse(underlying, hi)); |
| this.lo = lo; |
| this.hi = hi; |
| } |
| |
| private static ArrayData maybeSparse(final ArrayData underlying, final long hi) { |
| if (hi < SparseArrayData.MAX_DENSE_LENGTH || underlying instanceof SparseArrayData) { |
| return underlying; |
| } |
| return new SparseArrayData(underlying, underlying.length()); |
| } |
| |
| private boolean isEmpty() { |
| return lo > hi; |
| } |
| |
| private boolean isDeleted(final int index) { |
| final long longIndex = ArrayIndex.toLongIndex(index); |
| return lo <= longIndex && longIndex <= hi; |
| } |
| |
| @Override |
| public ArrayData copy() { |
| return new DeletedRangeArrayFilter(underlying.copy(), lo, hi); |
| } |
| |
| @Override |
| public Object[] asObjectArray() { |
| final Object[] value = super.asObjectArray(); |
| |
| if (lo < Integer.MAX_VALUE) { |
| final int end = (int)Math.min(hi + 1, Integer.MAX_VALUE); |
| for (int i = (int)lo; i < end; i++) { |
| value[i] = ScriptRuntime.UNDEFINED; |
| } |
| } |
| |
| return value; |
| } |
| |
| @Override |
| public Object asArrayOfType(final Class<?> componentType) { |
| final Object value = super.asArrayOfType(componentType); |
| final Object undefValue = convertUndefinedValue(componentType); |
| |
| if (lo < Integer.MAX_VALUE) { |
| final int end = (int)Math.min(hi + 1, Integer.MAX_VALUE); |
| for (int i = (int)lo; i < end; i++) { |
| Array.set(value, i, undefValue); |
| } |
| } |
| |
| return value; |
| } |
| |
| @Override |
| public ArrayData ensure(final long safeIndex) { |
| if (safeIndex >= SparseArrayData.MAX_DENSE_LENGTH && safeIndex >= length()) { |
| return new SparseArrayData(this, safeIndex + 1); |
| } |
| |
| return super.ensure(safeIndex); |
| } |
| |
| @Override |
| public void shiftLeft(final int by) { |
| super.shiftLeft(by); |
| lo = Math.max(0, lo - by); |
| hi = Math.max(-1, hi - by); |
| } |
| |
| @Override |
| public ArrayData shiftRight(final int by) { |
| super.shiftRight(by); |
| final long len = length(); |
| lo = Math.min(len, lo + by); |
| hi = Math.min(len - 1, hi + by); |
| |
| return isEmpty() ? getUnderlying() : this; |
| } |
| |
| @Override |
| public ArrayData shrink(final long newLength) { |
| super.shrink(newLength); |
| lo = Math.min(newLength, lo); |
| hi = Math.min(newLength - 1, hi); |
| |
| return isEmpty() ? getUnderlying() : this; |
| } |
| |
| @Override |
| public ArrayData set(final int index, final Object value, final boolean strict) { |
| final long longIndex = ArrayIndex.toLongIndex(index); |
| if (longIndex < lo || longIndex > hi) { |
| return super.set(index, value, strict); |
| } else if (longIndex > lo && longIndex < hi) { |
| return getDeletedArrayFilter().set(index, value, strict); |
| } |
| if (longIndex == lo) { |
| lo++; |
| } else { |
| assert longIndex == hi; |
| hi--; |
| } |
| |
| return isEmpty() ? getUnderlying().set(index, value, strict) : super.set(index, value, strict); |
| } |
| |
| @Override |
| public ArrayData set(final int index, final int value, final boolean strict) { |
| final long longIndex = ArrayIndex.toLongIndex(index); |
| if (longIndex < lo || longIndex > hi) { |
| return super.set(index, value, strict); |
| } else if (longIndex > lo && longIndex < hi) { |
| return getDeletedArrayFilter().set(index, value, strict); |
| } |
| if (longIndex == lo) { |
| lo++; |
| } else { |
| assert longIndex == hi; |
| hi--; |
| } |
| |
| return isEmpty() ? getUnderlying().set(index, value, strict) : super.set(index, value, strict); |
| } |
| |
| @Override |
| public ArrayData set(final int index, final long value, final boolean strict) { |
| final long longIndex = ArrayIndex.toLongIndex(index); |
| if (longIndex < lo || longIndex > hi) { |
| return super.set(index, value, strict); |
| } else if (longIndex > lo && longIndex < hi) { |
| return getDeletedArrayFilter().set(index, value, strict); |
| } |
| if (longIndex == lo) { |
| lo++; |
| } else { |
| assert longIndex == hi; |
| hi--; |
| } |
| |
| return isEmpty() ? getUnderlying().set(index, value, strict) : super.set(index, value, strict); |
| } |
| |
| @Override |
| public ArrayData set(final int index, final double value, final boolean strict) { |
| final long longIndex = ArrayIndex.toLongIndex(index); |
| if (longIndex < lo || longIndex > hi) { |
| return super.set(index, value, strict); |
| } else if (longIndex > lo && longIndex < hi) { |
| return getDeletedArrayFilter().set(index, value, strict); |
| } |
| if (longIndex == lo) { |
| lo++; |
| } else { |
| assert longIndex == hi; |
| hi--; |
| } |
| |
| return isEmpty() ? getUnderlying().set(index, value, strict) : super.set(index, value, strict); |
| } |
| |
| @Override |
| public boolean has(final int index) { |
| return super.has(index) && !isDeleted(index); |
| } |
| |
| private ArrayData getDeletedArrayFilter() { |
| final ArrayData deleteFilter = new DeletedArrayFilter(getUnderlying()); |
| deleteFilter.delete(lo, hi); |
| return deleteFilter; |
| } |
| |
| @Override |
| public ArrayData delete(final int index) { |
| final long longIndex = ArrayIndex.toLongIndex(index); |
| underlying.setEmpty(index); |
| |
| if (longIndex + 1 == lo) { |
| lo = longIndex; |
| } else if (longIndex - 1 == hi) { |
| hi = longIndex; |
| } else if (longIndex < lo || hi < longIndex) { |
| return getDeletedArrayFilter().delete(index); |
| } |
| |
| return this; |
| } |
| |
| @Override |
| public ArrayData delete(final long fromIndex, final long toIndex) { |
| if (fromIndex > hi + 1 || toIndex < lo - 1) { |
| return getDeletedArrayFilter().delete(fromIndex, toIndex); |
| } |
| lo = Math.min(fromIndex, lo); |
| hi = Math.max(toIndex, hi); |
| underlying.setEmpty(lo, hi); |
| return this; |
| } |
| |
| @Override |
| public Object pop() { |
| final int index = (int)length() - 1; |
| if (super.has(index)) { |
| final boolean isDeleted = isDeleted(index); |
| final Object value = super.pop(); |
| |
| lo = Math.min(index + 1, lo); |
| hi = Math.min(index, hi); |
| return isDeleted ? ScriptRuntime.UNDEFINED : value; |
| } |
| |
| return super.pop(); |
| } |
| |
| @Override |
| public ArrayData slice(final long from, final long to) { |
| return new DeletedRangeArrayFilter(underlying.slice(from, to), Math.max(0, lo - from), Math.max(0, hi - from)); |
| } |
| } |