J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2002-2004 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | /* |
| 27 | * (C) Copyright IBM Corp. 2000 - All Rights Reserved |
| 28 | * |
| 29 | * The original version of this source code and documentation is |
| 30 | * copyrighted and owned by IBM. These materials are provided |
| 31 | * under terms of a License Agreement between IBM and Sun. |
| 32 | * This technology is protected by multiple US and International |
| 33 | * patents. This notice and attribution to IBM may not be removed. |
| 34 | * |
| 35 | */ |
| 36 | |
| 37 | package com.sun.inputmethods.internal.indicim; |
| 38 | |
| 39 | import java.awt.im.spi.InputMethodContext; |
| 40 | |
| 41 | import java.awt.event.KeyEvent; |
| 42 | import java.awt.event.InputMethodEvent; |
| 43 | import java.awt.font.TextAttribute; |
| 44 | import java.awt.font.TextHitInfo; |
| 45 | |
| 46 | import java.text.AttributedCharacterIterator; |
| 47 | |
| 48 | import java.util.Hashtable; |
| 49 | import java.util.HashSet; |
| 50 | import java.util.Map; |
| 51 | import java.util.Set; |
| 52 | |
| 53 | class IndicInputMethodImpl { |
| 54 | |
| 55 | protected char[] KBD_MAP; |
| 56 | |
| 57 | private static final char SUBSTITUTION_BASE = '\uff00'; |
| 58 | |
| 59 | // Indexed by map value - SUBSTITUTION_BASE |
| 60 | protected char[][] SUBSTITUTION_TABLE; |
| 61 | |
| 62 | // Invalid character. |
| 63 | private static final char INVALID_CHAR = '\uffff'; |
| 64 | |
| 65 | // Unmapped versions of some interesting characters. |
| 66 | private static final char KEY_SIGN_VIRAMA = '\u0064'; // or just 'd'?? |
| 67 | private static final char KEY_SIGN_NUKTA = '\u005d'; // or just ']'?? |
| 68 | |
| 69 | // Two succeeding viramas are replaced by one virama and one ZWNJ. |
| 70 | // Viram followed by Nukta is replaced by one VIRAMA and one ZWJ |
| 71 | private static final char ZWJ = '\u200d'; |
| 72 | private static final char ZWNJ = '\u200c'; |
| 73 | |
| 74 | // Backspace |
| 75 | private static final char BACKSPACE = '\u0008'; |
| 76 | |
| 77 | // Sorted list of characters which can be followed by Nukta |
| 78 | protected char[] JOIN_WITH_NUKTA; |
| 79 | |
| 80 | // Nukta form of the above characters |
| 81 | protected char[] NUKTA_FORM; |
| 82 | |
| 83 | private int log2; |
| 84 | private int power; |
| 85 | private int extra; |
| 86 | |
| 87 | // cached TextHitInfo. Only one type of TextHitInfo is required. |
| 88 | private static final TextHitInfo ZERO_TRAILING_HIT_INFO = TextHitInfo.trailing(0); |
| 89 | |
| 90 | /** |
| 91 | * Returns the index of the given character in the JOIN_WITH_NUKTA array. |
| 92 | * If character is not found, -1 is returned. |
| 93 | */ |
| 94 | private int nuktaIndex(char ch) { |
| 95 | |
| 96 | if (JOIN_WITH_NUKTA == null) { |
| 97 | return -1; |
| 98 | } |
| 99 | |
| 100 | int probe = power; |
| 101 | int index = 0; |
| 102 | |
| 103 | if (JOIN_WITH_NUKTA[extra] <= ch) { |
| 104 | index = extra; |
| 105 | } |
| 106 | |
| 107 | while (probe > (1 << 0)) { |
| 108 | probe >>= 1; |
| 109 | |
| 110 | if (JOIN_WITH_NUKTA[index + probe] <= ch) { |
| 111 | index += probe; |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | if (JOIN_WITH_NUKTA[index] != ch) { |
| 116 | index = -1; |
| 117 | } |
| 118 | |
| 119 | return index; |
| 120 | } |
| 121 | |
| 122 | /** |
| 123 | * Returns the equivalent character for hindi locale. |
| 124 | * @param originalChar The original character. |
| 125 | */ |
| 126 | private char getMappedChar( char originalChar ) |
| 127 | { |
| 128 | if (originalChar <= KBD_MAP.length) { |
| 129 | return KBD_MAP[originalChar]; |
| 130 | } |
| 131 | |
| 132 | return originalChar; |
| 133 | }//getMappedChar() |
| 134 | |
| 135 | // Array used to hold the text to be sent. |
| 136 | // If the last character was not committed it is stored in text[0]. |
| 137 | // The variable totalChars give an indication of whether the last |
| 138 | // character was committed or not. If at any time ( but not within a |
| 139 | // a call to dispatchEvent ) totalChars is not equal to 0 ( it can |
| 140 | // only be 1 otherwise ) the last character was not committed. |
| 141 | private char [] text = new char[4]; |
| 142 | |
| 143 | // this is always 0 before and after call to dispatchEvent. This character assumes |
| 144 | // significance only within a call to dispatchEvent. |
| 145 | private int committedChars = 0;// number of committed characters |
| 146 | |
| 147 | // the total valid characters in variable text currently. |
| 148 | private int totalChars = 0;//number of total characters ( committed + composed ) |
| 149 | |
| 150 | private boolean lastCharWasVirama = false; |
| 151 | |
| 152 | private InputMethodContext context; |
| 153 | |
| 154 | // |
| 155 | // Finds the high bit by binary searching |
| 156 | // through the bits in n. |
| 157 | // |
| 158 | private static byte highBit(int n) |
| 159 | { |
| 160 | if (n <= 0) { |
| 161 | return -32; |
| 162 | } |
| 163 | |
| 164 | byte bit = 0; |
| 165 | |
| 166 | if (n >= 1 << 16) { |
| 167 | n >>= 16; |
| 168 | bit += 16; |
| 169 | } |
| 170 | |
| 171 | if (n >= 1 << 8) { |
| 172 | n >>= 8; |
| 173 | bit += 8; |
| 174 | } |
| 175 | |
| 176 | if (n >= 1 << 4) { |
| 177 | n >>= 4; |
| 178 | bit += 4; |
| 179 | } |
| 180 | |
| 181 | if (n >= 1 << 2) { |
| 182 | n >>= 2; |
| 183 | bit += 2; |
| 184 | } |
| 185 | |
| 186 | if (n >= 1 << 1) { |
| 187 | n >>= 1; |
| 188 | bit += 1; |
| 189 | } |
| 190 | |
| 191 | return bit; |
| 192 | } |
| 193 | |
| 194 | IndicInputMethodImpl(char[] keyboardMap, char[] joinWithNukta, char[] nuktaForm, |
| 195 | char[][] substitutionTable) { |
| 196 | KBD_MAP = keyboardMap; |
| 197 | JOIN_WITH_NUKTA = joinWithNukta; |
| 198 | NUKTA_FORM = nuktaForm; |
| 199 | SUBSTITUTION_TABLE = substitutionTable; |
| 200 | |
| 201 | if (JOIN_WITH_NUKTA != null) { |
| 202 | int log2 = highBit(JOIN_WITH_NUKTA.length); |
| 203 | |
| 204 | power = 1 << log2; |
| 205 | extra = JOIN_WITH_NUKTA.length - power; |
| 206 | } else { |
| 207 | power = extra = 0; |
| 208 | } |
| 209 | |
| 210 | } |
| 211 | |
| 212 | void setInputMethodContext(InputMethodContext context) { |
| 213 | |
| 214 | this.context = context; |
| 215 | } |
| 216 | |
| 217 | void handleKeyTyped(KeyEvent kevent) { |
| 218 | |
| 219 | char keyChar = kevent.getKeyChar(); |
| 220 | char currentChar = getMappedChar(keyChar); |
| 221 | |
| 222 | // The Explicit and Soft Halanta case. |
| 223 | if ( lastCharWasVirama ) { |
| 224 | switch (keyChar) { |
| 225 | case KEY_SIGN_NUKTA: |
| 226 | currentChar = ZWJ; |
| 227 | break; |
| 228 | case KEY_SIGN_VIRAMA: |
| 229 | currentChar = ZWNJ; |
| 230 | break; |
| 231 | default: |
| 232 | }//endSwitch |
| 233 | }//endif |
| 234 | |
| 235 | if (currentChar == INVALID_CHAR) { |
| 236 | kevent.consume(); |
| 237 | return; |
| 238 | } |
| 239 | |
| 240 | if (currentChar == BACKSPACE) { |
| 241 | lastCharWasVirama = false; |
| 242 | |
| 243 | if (totalChars > 0) { |
| 244 | totalChars = committedChars = 0; |
| 245 | } else { |
| 246 | return; |
| 247 | } |
| 248 | } |
| 249 | else if (keyChar == KEY_SIGN_NUKTA) { |
| 250 | int nuktaIndex = nuktaIndex(text[0]); |
| 251 | |
| 252 | if (nuktaIndex != -1) { |
| 253 | text[0] = NUKTA_FORM[nuktaIndex]; |
| 254 | } else { |
| 255 | // the last character was committed, commit just Nukta. |
| 256 | // Note : the lastChar must have been committed if it is not one of |
| 257 | // the characters which combine with nukta. |
| 258 | // the state must be totalChars = committedChars = 0; |
| 259 | text[totalChars++] = currentChar; |
| 260 | } |
| 261 | |
| 262 | committedChars += 1; |
| 263 | } |
| 264 | else { |
| 265 | int nuktaIndex = nuktaIndex(currentChar); |
| 266 | |
| 267 | if (nuktaIndex != -1) { |
| 268 | // Commit everything but currentChar |
| 269 | text[totalChars++] = currentChar; |
| 270 | committedChars = totalChars-1; |
| 271 | } else { |
| 272 | if (currentChar >= SUBSTITUTION_BASE) { |
| 273 | char[] sub = SUBSTITUTION_TABLE[currentChar - SUBSTITUTION_BASE]; |
| 274 | |
| 275 | System.arraycopy(sub, 0, text, totalChars, sub.length); |
| 276 | totalChars += sub.length; |
| 277 | } else { |
| 278 | text[totalChars++] = currentChar; |
| 279 | } |
| 280 | |
| 281 | committedChars = totalChars; |
| 282 | } |
| 283 | } |
| 284 | |
| 285 | ACIText aText = new ACIText( text, 0, totalChars, committedChars ); |
| 286 | int composedCharLength = totalChars - committedChars; |
| 287 | TextHitInfo caret=null,visiblePosition=null; |
| 288 | switch( composedCharLength ) { |
| 289 | case 0: |
| 290 | break; |
| 291 | case 1: |
| 292 | visiblePosition = caret = ZERO_TRAILING_HIT_INFO; |
| 293 | break; |
| 294 | default: |
| 295 | assert false : "The code should not reach here. There is no case where there can be more than one character pending."; |
| 296 | } |
| 297 | |
| 298 | context.dispatchInputMethodEvent(InputMethodEvent.INPUT_METHOD_TEXT_CHANGED, |
| 299 | aText, |
| 300 | committedChars, |
| 301 | caret, |
| 302 | visiblePosition); |
| 303 | |
| 304 | if (totalChars == 0) { |
| 305 | text[0] = INVALID_CHAR; |
| 306 | } else { |
| 307 | text[0] = text[totalChars - 1];// make text[0] hold the last character |
| 308 | } |
| 309 | |
| 310 | lastCharWasVirama = keyChar == KEY_SIGN_VIRAMA && !lastCharWasVirama; |
| 311 | |
| 312 | totalChars -= committedChars; |
| 313 | committedChars = 0; |
| 314 | // state now text[0] = last character |
| 315 | // totalChars = ( last character committed )? 0 : 1; |
| 316 | // committedChars = 0; |
| 317 | |
| 318 | kevent.consume();// prevent client from getting this event. |
| 319 | }//dispatchEvent() |
| 320 | |
| 321 | void endComposition() { |
| 322 | if( totalChars != 0 ) {// if some character is not committed. |
| 323 | ACIText aText = new ACIText( text, 0, totalChars, totalChars ); |
| 324 | context.dispatchInputMethodEvent( InputMethodEvent.INPUT_METHOD_TEXT_CHANGED, |
| 325 | aText, totalChars, null, null ); |
| 326 | totalChars = committedChars = 0; |
| 327 | text[0] = INVALID_CHAR; |
| 328 | lastCharWasVirama = false; |
| 329 | }//end if |
| 330 | }//endComposition() |
| 331 | |
| 332 | // custom AttributedCharacterIterator -- much lightweight since currently there is no |
| 333 | // attribute defined on the text being generated by the input method. |
| 334 | private class ACIText implements AttributedCharacterIterator { |
| 335 | private char [] text = null; |
| 336 | private int committed = 0; |
| 337 | private int index = 0; |
| 338 | |
| 339 | ACIText( char [] chArray, int offset, int length, int committed ) { |
| 340 | this.text = new char[length]; |
| 341 | this.committed = committed; |
| 342 | System.arraycopy( chArray, offset, text, 0, length ); |
| 343 | }//c'tor |
| 344 | |
| 345 | // CharacterIterator methods. |
| 346 | public char first() { |
| 347 | return _setIndex( 0 ); |
| 348 | } |
| 349 | |
| 350 | public char last() { |
| 351 | if( text.length == 0 ) { |
| 352 | return _setIndex( text.length ); |
| 353 | } |
| 354 | return _setIndex( text.length - 1 ); |
| 355 | } |
| 356 | |
| 357 | public char current() { |
| 358 | if( index == text.length ) |
| 359 | return DONE; |
| 360 | return text[index]; |
| 361 | } |
| 362 | |
| 363 | public char next() { |
| 364 | if( index == text.length ) { |
| 365 | return DONE; |
| 366 | } |
| 367 | return _setIndex( index + 1 ); |
| 368 | } |
| 369 | |
| 370 | public char previous() { |
| 371 | if( index == 0 ) |
| 372 | return DONE; |
| 373 | return _setIndex( index - 1 ); |
| 374 | } |
| 375 | |
| 376 | public char setIndex(int position) { |
| 377 | if( position < 0 || position > text.length ) { |
| 378 | throw new IllegalArgumentException(); |
| 379 | } |
| 380 | return _setIndex( position ); |
| 381 | } |
| 382 | |
| 383 | public int getBeginIndex() { |
| 384 | return 0; |
| 385 | } |
| 386 | |
| 387 | public int getEndIndex() { |
| 388 | return text.length; |
| 389 | } |
| 390 | |
| 391 | public int getIndex() { |
| 392 | return index; |
| 393 | } |
| 394 | |
| 395 | public Object clone() { |
| 396 | try { |
| 397 | ACIText clone = (ACIText) super.clone(); |
| 398 | return clone; |
| 399 | } catch (CloneNotSupportedException e) { |
| 400 | throw new InternalError(); |
| 401 | } |
| 402 | } |
| 403 | |
| 404 | |
| 405 | // AttributedCharacterIterator methods. |
| 406 | public int getRunStart() { |
| 407 | return index >= committed ? committed : 0; |
| 408 | } |
| 409 | |
| 410 | public int getRunStart(AttributedCharacterIterator.Attribute attribute) { |
| 411 | return (index >= committed && |
| 412 | attribute == TextAttribute.INPUT_METHOD_UNDERLINE) ? committed : 0; |
| 413 | } |
| 414 | |
| 415 | public int getRunStart(Set<? extends Attribute> attributes) { |
| 416 | return (index >= committed && |
| 417 | attributes.contains(TextAttribute.INPUT_METHOD_UNDERLINE)) ? committed : 0; |
| 418 | } |
| 419 | |
| 420 | public int getRunLimit() { |
| 421 | return index < committed ? committed : text.length; |
| 422 | } |
| 423 | |
| 424 | public int getRunLimit(AttributedCharacterIterator.Attribute attribute) { |
| 425 | return (index < committed && |
| 426 | attribute == TextAttribute.INPUT_METHOD_UNDERLINE) ? committed : text.length; |
| 427 | } |
| 428 | |
| 429 | public int getRunLimit(Set<? extends Attribute> attributes) { |
| 430 | return (index < committed && |
| 431 | attributes.contains(TextAttribute.INPUT_METHOD_UNDERLINE)) ? committed : text.length; |
| 432 | } |
| 433 | |
| 434 | public Map getAttributes() { |
| 435 | Hashtable result = new Hashtable(); |
| 436 | if (index >= committed && committed < text.length) { |
| 437 | result.put(TextAttribute.INPUT_METHOD_UNDERLINE, |
| 438 | TextAttribute.UNDERLINE_LOW_ONE_PIXEL); |
| 439 | } |
| 440 | return result; |
| 441 | } |
| 442 | |
| 443 | public Object getAttribute(AttributedCharacterIterator.Attribute attribute) { |
| 444 | if (index >= committed && |
| 445 | committed < text.length && |
| 446 | attribute == TextAttribute.INPUT_METHOD_UNDERLINE) { |
| 447 | |
| 448 | return TextAttribute.UNDERLINE_LOW_ONE_PIXEL; |
| 449 | } |
| 450 | return null; |
| 451 | } |
| 452 | |
| 453 | public Set getAllAttributeKeys() { |
| 454 | HashSet result = new HashSet(); |
| 455 | if (committed < text.length) { |
| 456 | result.add(TextAttribute.INPUT_METHOD_UNDERLINE); |
| 457 | } |
| 458 | return result; |
| 459 | } |
| 460 | |
| 461 | // private methods |
| 462 | |
| 463 | /** |
| 464 | * This is always called with valid i ( 0 < i <= text.length ) |
| 465 | */ |
| 466 | private char _setIndex( int i ) { |
| 467 | index = i; |
| 468 | if( i == text.length ) { |
| 469 | return DONE; |
| 470 | } |
| 471 | return text[i]; |
| 472 | }//_setIndex() |
| 473 | |
| 474 | }//end of inner class |
| 475 | } |