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| 1 | /* | ||
| 2 | * Copyright (c) 1996, 2005, 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 | /* | ||
| 27 | * (C) Copyright Taligent, Inc. 1996 - All Rights Reserved | ||
| 28 | * (C) Copyright IBM Corp. 1996 - All Rights Reserved | ||
| 29 | * | ||
| 30 | * The original version of this source code and documentation is copyrighted | ||
| 31 | * and owned by Taligent, Inc., a wholly-owned subsidiary of IBM. These | ||
| 32 | * materials are provided under terms of a License Agreement between Taligent | ||
| 33 | * and Sun. This technology is protected by multiple US and International | ||
| 34 | * patents. This notice and attribution to Taligent may not be removed. | ||
| 35 | * Taligent is a registered trademark of Taligent, Inc. | ||
| 36 | * | ||
| 37 | */ | ||
| 38 | |||
| 39 | package sun.text; | ||
| 40 | |||
| 41 | |||
| 42 | /** | ||
| 43 | * class CompactATypeArray : use only on primitive data types | ||
| 44 | * Provides a compact way to store information that is indexed by Unicode | ||
| 45 | * values, such as character properties, types, keyboard values, etc.This | ||
| 46 | * is very useful when you have a block of Unicode data that contains | ||
| 47 | * significant values while the rest of the Unicode data is unused in the | ||
| 48 | * application or when you have a lot of redundance, such as where all 21,000 | ||
| 49 | * Han ideographs have the same value. However, lookup is much faster than a | ||
| 50 | * hash table. | ||
| 51 | * A compact array of any primitive data type serves two purposes: | ||
| 52 | * <UL type = round> | ||
| 53 | * <LI>Fast access of the indexed values. | ||
| 54 | * <LI>Smaller memory footprint. | ||
| 55 | * </UL> | ||
| 56 | * A compact array is composed of a index array and value array. The index | ||
| 57 | * array contains the indicies of Unicode characters to the value array. | ||
| 58 | * | ||
| 59 | * @see CompactIntArray | ||
| 60 | * @see CompactShortArray | ||
| 61 | * @author Helena Shih | ||
| 62 | */ | ||
| 63 | public final class CompactByteArray implements Cloneable { | ||
| 64 | |||
| 65 | /** | ||
| 66 | * The total number of Unicode characters. | ||
| 67 | */ | ||
| 68 | public static final int UNICODECOUNT =65536; | ||
| 69 | |||
| 70 | /** | ||
| 71 | * Constructor for CompactByteArray. | ||
| 72 | * @param defaultValue the default value of the compact array. | ||
| 73 | */ | ||
| 74 | public CompactByteArray(byte defaultValue) | ||
| 75 | { | ||
| 76 | int i; | ||
| 77 | values = new byte[UNICODECOUNT]; | ||
| 78 | indices = new short[INDEXCOUNT]; | ||
| 79 | hashes = new int[INDEXCOUNT]; | ||
| 80 | for (i = 0; i < UNICODECOUNT; ++i) { | ||
| 81 | values[i] = defaultValue; | ||
| 82 | } | ||
| 83 | for (i = 0; i < INDEXCOUNT; ++i) { | ||
| 84 | indices[i] = (short)(i<<BLOCKSHIFT); | ||
| 85 | hashes[i] = 0; | ||
| 86 | } | ||
| 87 | isCompact = false; | ||
| 88 | } | ||
| 89 | |||
| 90 | /** | ||
| 91 | * Constructor for CompactByteArray. | ||
| 92 | * @param indexArray the indicies of the compact array. | ||
| 93 | * @param newValues the values of the compact array. | ||
| 94 | * @exception IllegalArgumentException If index is out of range. | ||
| 95 | */ | ||
| 96 | public CompactByteArray(short indexArray[], | ||
| 97 | byte newValues[]) | ||
| 98 | { | ||
| 99 | int i; | ||
| 100 | if (indexArray.length != INDEXCOUNT) | ||
| 101 | throw new IllegalArgumentException("Index out of bounds!"); | ||
| 102 | for (i = 0; i < INDEXCOUNT; ++i) { | ||
| 103 | short index = indexArray[i]; | ||
| 104 | if ((index < 0) || (index >= newValues.length+BLOCKCOUNT)) | ||
| 105 | throw new IllegalArgumentException("Index out of bounds!"); | ||
| 106 | } | ||
| 107 | indices = indexArray; | ||
| 108 | values = newValues; | ||
| 109 | isCompact = true; | ||
| 110 | } | ||
| 111 | |||
| 112 | /** | ||
| 113 | * Get the mapped value of a Unicode character. | ||
| 114 | * @param index the character to get the mapped value with | ||
| 115 | * @return the mapped value of the given character | ||
| 116 | */ | ||
| 117 | public byte elementAt(char index) | ||
| 118 | { | ||
| 119 | return (values[(indices[index >> BLOCKSHIFT] & 0xFFFF) | ||
| 120 | + (index & BLOCKMASK)]); | ||
| 121 | } | ||
| 122 | /** | ||
| 123 | * Set a new value for a Unicode character. | ||
| 124 | * Set automatically expands the array if it is compacted. | ||
| 125 | * @param index the character to set the mapped value with | ||
| 126 | * @param value the new mapped value | ||
| 127 | */ | ||
| 128 | public void setElementAt(char index, byte value) | ||
| 129 | { | ||
| 130 | if (isCompact) | ||
| 131 | expand(); | ||
| 132 | values[(int)index] = value; | ||
| 133 | touchBlock(index >> BLOCKSHIFT, value); | ||
| 134 | } | ||
| 135 | |||
| 136 | /** | ||
| 137 | * Set new values for a range of Unicode character. | ||
| 138 | * @param start the starting offset o of the range | ||
| 139 | * @param end the ending offset of the range | ||
| 140 | * @param value the new mapped value | ||
| 141 | */ | ||
| 142 | public void setElementAt(char start, char end, byte value) | ||
| 143 | { | ||
| 144 | int i; | ||
| 145 | if (isCompact) { | ||
| 146 | expand(); | ||
| 147 | } | ||
| 148 | for (i = start; i <= end; ++i) { | ||
| 149 | values[i] = value; | ||
| 150 | touchBlock(i >> BLOCKSHIFT, value); | ||
| 151 | } | ||
| 152 | } | ||
| 153 | |||
| 154 | /** | ||
| 155 | *Compact the array. | ||
| 156 | */ | ||
| 157 | public void compact() | ||
| 158 | { | ||
| 159 | if (!isCompact) { | ||
| 160 | int limitCompacted = 0; | ||
| 161 | int iBlockStart = 0; | ||
| 162 | short iUntouched = -1; | ||
| 163 | |||
| 164 | for (int i = 0; i < indices.length; ++i, iBlockStart += BLOCKCOUNT) { | ||
| 165 | indices[i] = -1; | ||
| 166 | boolean touched = blockTouched(i); | ||
| 167 | if (!touched && iUntouched != -1) { | ||
| 168 | // If no values in this block were set, we can just set its | ||
| 169 | // index to be the same as some other block with no values | ||
| 170 | // set, assuming we've seen one yet. | ||
| 171 | indices[i] = iUntouched; | ||
| 172 | } else { | ||
| 173 | int jBlockStart = 0; | ||
| 174 | int j = 0; | ||
| 175 | for (j = 0; j < limitCompacted; | ||
| 176 | ++j, jBlockStart += BLOCKCOUNT) { | ||
| 177 | if (hashes[i] == hashes[j] && | ||
| 178 | arrayRegionMatches(values, iBlockStart, | ||
| 179 | values, jBlockStart, BLOCKCOUNT)) { | ||
| 180 | indices[i] = (short)jBlockStart; | ||
| 181 | break; | ||
| 182 | } | ||
| 183 | } | ||
| 184 | if (indices[i] == -1) { | ||
| 185 | // we didn't match, so copy & update | ||
| 186 | System.arraycopy(values, iBlockStart, | ||
| 187 | values, jBlockStart, BLOCKCOUNT); | ||
| 188 | indices[i] = (short)jBlockStart; | ||
| 189 | hashes[j] = hashes[i]; | ||
| 190 | ++limitCompacted; | ||
| 191 | |||
| 192 | if (!touched) { | ||
| 193 | // If this is the first untouched block we've seen, | ||
| 194 | // remember its index. | ||
| 195 | iUntouched = (short)jBlockStart; | ||
| 196 | } | ||
| 197 | } | ||
| 198 | } | ||
| 199 | } | ||
| 200 | // we are done compacting, so now make the array shorter | ||
| 201 | int newSize = limitCompacted*BLOCKCOUNT; | ||
| 202 | byte[] result = new byte[newSize]; | ||
| 203 | System.arraycopy(values, 0, result, 0, newSize); | ||
| 204 | values = result; | ||
| 205 | isCompact = true; | ||
| 206 | hashes = null; | ||
| 207 | } | ||
| 208 | } | ||
| 209 | |||
| 210 | /** | ||
| 211 | * Convenience utility to compare two arrays of doubles. | ||
| 212 | * @param len the length to compare. | ||
| 213 | * The start indices and start+len must be valid. | ||
| 214 | */ | ||
| 215 | final static boolean arrayRegionMatches(byte[] source, int sourceStart, | ||
| 216 | byte[] target, int targetStart, | ||
| 217 | int len) | ||
| 218 | { | ||
| 219 | int sourceEnd = sourceStart + len; | ||
| 220 | int delta = targetStart - sourceStart; | ||
| 221 | for (int i = sourceStart; i < sourceEnd; i++) { | ||
| 222 | if (source[i] != target[i + delta]) | ||
| 223 | return false; | ||
| 224 | } | ||
| 225 | return true; | ||
| 226 | } | ||
| 227 | |||
| 228 | /** | ||
| 229 | * Remember that a specified block was "touched", i.e. had a value set. | ||
| 230 | * Untouched blocks can be skipped when compacting the array | ||
| 231 | */ | ||
| 232 | private final void touchBlock(int i, int value) { | ||
| 233 | hashes[i] = (hashes[i] + (value<<1)) | 1; | ||
| 234 | } | ||
| 235 | |||
| 236 | /** | ||
| 237 | * Query whether a specified block was "touched", i.e. had a value set. | ||
| 238 | * Untouched blocks can be skipped when compacting the array | ||
| 239 | */ | ||
| 240 | private final boolean blockTouched(int i) { | ||
| 241 | return hashes[i] != 0; | ||
| 242 | } | ||
| 243 | |||
| 244 | /** For internal use only. Do not modify the result, the behavior of | ||
| 245 | * modified results are undefined. | ||
| 246 | */ | ||
| 247 | public short getIndexArray()[] | ||
| 248 | { | ||
| 249 | return indices; | ||
| 250 | } | ||
| 251 | |||
| 252 | /** For internal use only. Do not modify the result, the behavior of | ||
| 253 | * modified results are undefined. | ||
| 254 | */ | ||
| 255 | public byte getStringArray()[] | ||
| 256 | { | ||
| 257 | return values; | ||
| 258 | } | ||
| 259 | |||
| 260 | /** | ||
| 261 | * Overrides Cloneable | ||
| 262 | */ | ||
| 263 | public Object clone() | ||
| 264 | { | ||
| 265 | try { | ||
| 266 | CompactByteArray other = (CompactByteArray) super.clone(); | ||
| 267 | other.values = (byte[])values.clone(); | ||
| 268 | other.indices = (short[])indices.clone(); | ||
| 269 | if (hashes != null) other.hashes = (int[])hashes.clone(); | ||
| 270 | return other; | ||
| 271 | } catch (CloneNotSupportedException e) { | ||
| 272 | throw new InternalError(); | ||
| 273 | } | ||
| 274 | } | ||
| 275 | |||
| 276 | /** | ||
| 277 | * Compares the equality of two compact array objects. | ||
| 278 | * @param obj the compact array object to be compared with this. | ||
| 279 | * @return true if the current compact array object is the same | ||
| 280 | * as the compact array object obj; false otherwise. | ||
| 281 | */ | ||
| 282 | public boolean equals(Object obj) { | ||
| 283 | if (obj == null) return false; | ||
| 284 | if (this == obj) // quick check | ||
| 285 | return true; | ||
| 286 | if (getClass() != obj.getClass()) // same class? | ||
| 287 | return false; | ||
| 288 | CompactByteArray other = (CompactByteArray) obj; | ||
| 289 | for (int i = 0; i < UNICODECOUNT; i++) { | ||
| 290 | // could be sped up later | ||
| 291 | if (elementAt((char)i) != other.elementAt((char)i)) | ||
| 292 | return false; | ||
| 293 | } | ||
| 294 | return true; // we made it through the guantlet. | ||
| 295 | } | ||
| 296 | |||
| 297 | /** | ||
| 298 | * Generates the hash code for the compact array object | ||
| 299 | */ | ||
| 300 | |||
| 301 | public int hashCode() { | ||
| 302 | int result = 0; | ||
| 303 | int increment = Math.min(3, values.length/16); | ||
| 304 | for (int i = 0; i < values.length; i+= increment) { | ||
| 305 | result = result * 37 + values[i]; | ||
| 306 | } | ||
| 307 | return result; | ||
| 308 | } | ||
| 309 | |||
| 310 | // -------------------------------------------------------------- | ||
| 311 | // package private | ||
| 312 | // -------------------------------------------------------------- | ||
| 313 | /** | ||
| 314 | * Expanding takes the array back to a 65536 element array. | ||
| 315 | */ | ||
| 316 | private void expand() | ||
| 317 | { | ||
| 318 | int i; | ||
| 319 | if (isCompact) { | ||
| 320 | byte[] tempArray; | ||
| 321 | hashes = new int[INDEXCOUNT]; | ||
| 322 | tempArray = new byte[UNICODECOUNT]; | ||
| 323 | for (i = 0; i < UNICODECOUNT; ++i) { | ||
| 324 | byte value = elementAt((char)i); | ||
| 325 | tempArray[i] = value; | ||
| 326 | touchBlock(i >> BLOCKSHIFT, value); | ||
| 327 | } | ||
| 328 | for (i = 0; i < INDEXCOUNT; ++i) { | ||
| 329 | indices[i] = (short)(i<<BLOCKSHIFT); | ||
| 330 | } | ||
| 331 | values = null; | ||
| 332 | values = tempArray; | ||
| 333 | isCompact = false; | ||
| 334 | } | ||
| 335 | } | ||
| 336 | |||
| 337 | private byte[] getArray() | ||
| 338 | { | ||
| 339 | return values; | ||
| 340 | } | ||
| 341 | |||
| 342 | private static final int BLOCKSHIFT =7; | ||
| 343 | private static final int BLOCKCOUNT =(1<<BLOCKSHIFT); | ||
| 344 | private static final int INDEXSHIFT =(16-BLOCKSHIFT); | ||
| 345 | private static final int INDEXCOUNT =(1<<INDEXSHIFT); | ||
| 346 | private static final int BLOCKMASK = BLOCKCOUNT - 1; | ||
| 347 | |||
| 348 | private byte[] values; // char -> short (char parameterized short) | ||
| 349 | private short indices[]; | ||
| 350 | private boolean isCompact; | ||
| 351 | private int[] hashes; | ||
| 352 | }; | ||