| /* |
| * Copyright (c) 1996, 2005, 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. |
| */ |
| |
| /* |
| * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved |
| * (C) Copyright IBM Corp. 1996 - All Rights Reserved |
| * |
| * The original version of this source code and documentation is copyrighted |
| * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These |
| * materials are provided under terms of a License Agreement between Taligent |
| * and Sun. This technology is protected by multiple US and International |
| * patents. This notice and attribution to Taligent may not be removed. |
| * Taligent is a registered trademark of Taligent, Inc. |
| * |
| */ |
| |
| package sun.text; |
| |
| |
| /** |
| * class CompactATypeArray : use only on primitive data types |
| * Provides a compact way to store information that is indexed by Unicode |
| * values, such as character properties, types, keyboard values, etc.This |
| * is very useful when you have a block of Unicode data that contains |
| * significant values while the rest of the Unicode data is unused in the |
| * application or when you have a lot of redundance, such as where all 21,000 |
| * Han ideographs have the same value. However, lookup is much faster than a |
| * hash table. |
| * A compact array of any primitive data type serves two purposes: |
| * <UL type = round> |
| * <LI>Fast access of the indexed values. |
| * <LI>Smaller memory footprint. |
| * </UL> |
| * A compact array is composed of a index array and value array. The index |
| * array contains the indicies of Unicode characters to the value array. |
| * |
| * @see CompactIntArray |
| * @see CompactShortArray |
| * @author Helena Shih |
| */ |
| public final class CompactByteArray implements Cloneable { |
| |
| /** |
| * The total number of Unicode characters. |
| */ |
| public static final int UNICODECOUNT =65536; |
| |
| /** |
| * Constructor for CompactByteArray. |
| * @param defaultValue the default value of the compact array. |
| */ |
| public CompactByteArray(byte defaultValue) |
| { |
| int i; |
| values = new byte[UNICODECOUNT]; |
| indices = new short[INDEXCOUNT]; |
| hashes = new int[INDEXCOUNT]; |
| for (i = 0; i < UNICODECOUNT; ++i) { |
| values[i] = defaultValue; |
| } |
| for (i = 0; i < INDEXCOUNT; ++i) { |
| indices[i] = (short)(i<<BLOCKSHIFT); |
| hashes[i] = 0; |
| } |
| isCompact = false; |
| } |
| |
| /** |
| * Constructor for CompactByteArray. |
| * @param indexArray the indicies of the compact array. |
| * @param newValues the values of the compact array. |
| * @exception IllegalArgumentException If index is out of range. |
| */ |
| public CompactByteArray(short indexArray[], |
| byte newValues[]) |
| { |
| int i; |
| if (indexArray.length != INDEXCOUNT) |
| throw new IllegalArgumentException("Index out of bounds!"); |
| for (i = 0; i < INDEXCOUNT; ++i) { |
| short index = indexArray[i]; |
| if ((index < 0) || (index >= newValues.length+BLOCKCOUNT)) |
| throw new IllegalArgumentException("Index out of bounds!"); |
| } |
| indices = indexArray; |
| values = newValues; |
| isCompact = true; |
| } |
| |
| /** |
| * Get the mapped value of a Unicode character. |
| * @param index the character to get the mapped value with |
| * @return the mapped value of the given character |
| */ |
| public byte elementAt(char index) |
| { |
| return (values[(indices[index >> BLOCKSHIFT] & 0xFFFF) |
| + (index & BLOCKMASK)]); |
| } |
| /** |
| * Set a new value for a Unicode character. |
| * Set automatically expands the array if it is compacted. |
| * @param index the character to set the mapped value with |
| * @param value the new mapped value |
| */ |
| public void setElementAt(char index, byte value) |
| { |
| if (isCompact) |
| expand(); |
| values[(int)index] = value; |
| touchBlock(index >> BLOCKSHIFT, value); |
| } |
| |
| /** |
| * Set new values for a range of Unicode character. |
| * @param start the starting offset o of the range |
| * @param end the ending offset of the range |
| * @param value the new mapped value |
| */ |
| public void setElementAt(char start, char end, byte value) |
| { |
| int i; |
| if (isCompact) { |
| expand(); |
| } |
| for (i = start; i <= end; ++i) { |
| values[i] = value; |
| touchBlock(i >> BLOCKSHIFT, value); |
| } |
| } |
| |
| /** |
| *Compact the array. |
| */ |
| public void compact() |
| { |
| if (!isCompact) { |
| int limitCompacted = 0; |
| int iBlockStart = 0; |
| short iUntouched = -1; |
| |
| for (int i = 0; i < indices.length; ++i, iBlockStart += BLOCKCOUNT) { |
| indices[i] = -1; |
| boolean touched = blockTouched(i); |
| if (!touched && iUntouched != -1) { |
| // If no values in this block were set, we can just set its |
| // index to be the same as some other block with no values |
| // set, assuming we've seen one yet. |
| indices[i] = iUntouched; |
| } else { |
| int jBlockStart = 0; |
| int j = 0; |
| for (j = 0; j < limitCompacted; |
| ++j, jBlockStart += BLOCKCOUNT) { |
| if (hashes[i] == hashes[j] && |
| arrayRegionMatches(values, iBlockStart, |
| values, jBlockStart, BLOCKCOUNT)) { |
| indices[i] = (short)jBlockStart; |
| break; |
| } |
| } |
| if (indices[i] == -1) { |
| // we didn't match, so copy & update |
| System.arraycopy(values, iBlockStart, |
| values, jBlockStart, BLOCKCOUNT); |
| indices[i] = (short)jBlockStart; |
| hashes[j] = hashes[i]; |
| ++limitCompacted; |
| |
| if (!touched) { |
| // If this is the first untouched block we've seen, |
| // remember its index. |
| iUntouched = (short)jBlockStart; |
| } |
| } |
| } |
| } |
| // we are done compacting, so now make the array shorter |
| int newSize = limitCompacted*BLOCKCOUNT; |
| byte[] result = new byte[newSize]; |
| System.arraycopy(values, 0, result, 0, newSize); |
| values = result; |
| isCompact = true; |
| hashes = null; |
| } |
| } |
| |
| /** |
| * Convenience utility to compare two arrays of doubles. |
| * @param len the length to compare. |
| * The start indices and start+len must be valid. |
| */ |
| final static boolean arrayRegionMatches(byte[] source, int sourceStart, |
| byte[] target, int targetStart, |
| int len) |
| { |
| int sourceEnd = sourceStart + len; |
| int delta = targetStart - sourceStart; |
| for (int i = sourceStart; i < sourceEnd; i++) { |
| if (source[i] != target[i + delta]) |
| return false; |
| } |
| return true; |
| } |
| |
| /** |
| * Remember that a specified block was "touched", i.e. had a value set. |
| * Untouched blocks can be skipped when compacting the array |
| */ |
| private final void touchBlock(int i, int value) { |
| hashes[i] = (hashes[i] + (value<<1)) | 1; |
| } |
| |
| /** |
| * Query whether a specified block was "touched", i.e. had a value set. |
| * Untouched blocks can be skipped when compacting the array |
| */ |
| private final boolean blockTouched(int i) { |
| return hashes[i] != 0; |
| } |
| |
| /** For internal use only. Do not modify the result, the behavior of |
| * modified results are undefined. |
| */ |
| public short getIndexArray()[] |
| { |
| return indices; |
| } |
| |
| /** For internal use only. Do not modify the result, the behavior of |
| * modified results are undefined. |
| */ |
| public byte getStringArray()[] |
| { |
| return values; |
| } |
| |
| /** |
| * Overrides Cloneable |
| */ |
| public Object clone() |
| { |
| try { |
| CompactByteArray other = (CompactByteArray) super.clone(); |
| other.values = (byte[])values.clone(); |
| other.indices = (short[])indices.clone(); |
| if (hashes != null) other.hashes = (int[])hashes.clone(); |
| return other; |
| } catch (CloneNotSupportedException e) { |
| throw new InternalError(); |
| } |
| } |
| |
| /** |
| * Compares the equality of two compact array objects. |
| * @param obj the compact array object to be compared with this. |
| * @return true if the current compact array object is the same |
| * as the compact array object obj; false otherwise. |
| */ |
| public boolean equals(Object obj) { |
| if (obj == null) return false; |
| if (this == obj) // quick check |
| return true; |
| if (getClass() != obj.getClass()) // same class? |
| return false; |
| CompactByteArray other = (CompactByteArray) obj; |
| for (int i = 0; i < UNICODECOUNT; i++) { |
| // could be sped up later |
| if (elementAt((char)i) != other.elementAt((char)i)) |
| return false; |
| } |
| return true; // we made it through the guantlet. |
| } |
| |
| /** |
| * Generates the hash code for the compact array object |
| */ |
| |
| public int hashCode() { |
| int result = 0; |
| int increment = Math.min(3, values.length/16); |
| for (int i = 0; i < values.length; i+= increment) { |
| result = result * 37 + values[i]; |
| } |
| return result; |
| } |
| |
| // -------------------------------------------------------------- |
| // package private |
| // -------------------------------------------------------------- |
| /** |
| * Expanding takes the array back to a 65536 element array. |
| */ |
| private void expand() |
| { |
| int i; |
| if (isCompact) { |
| byte[] tempArray; |
| hashes = new int[INDEXCOUNT]; |
| tempArray = new byte[UNICODECOUNT]; |
| for (i = 0; i < UNICODECOUNT; ++i) { |
| byte value = elementAt((char)i); |
| tempArray[i] = value; |
| touchBlock(i >> BLOCKSHIFT, value); |
| } |
| for (i = 0; i < INDEXCOUNT; ++i) { |
| indices[i] = (short)(i<<BLOCKSHIFT); |
| } |
| values = null; |
| values = tempArray; |
| isCompact = false; |
| } |
| } |
| |
| private byte[] getArray() |
| { |
| return values; |
| } |
| |
| private static final int BLOCKSHIFT =7; |
| private static final int BLOCKCOUNT =(1<<BLOCKSHIFT); |
| private static final int INDEXSHIFT =(16-BLOCKSHIFT); |
| private static final int INDEXCOUNT =(1<<INDEXSHIFT); |
| private static final int BLOCKMASK = BLOCKCOUNT - 1; |
| |
| private byte[] values; // char -> short (char parameterized short) |
| private short indices[]; |
| private boolean isCompact; |
| private int[] hashes; |
| }; |
