1 /* 2 * Copyright (c) 1996, 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 /* 27 * (C) Copyright Taligent, Inc. 1996, 1997 - All Rights Reserved 28 * (C) Copyright IBM Corp. 1996 - 1998 - 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 java.text; 40 41 import java.io.InvalidObjectException; 42 import java.io.IOException; 43 import java.io.ObjectInputStream; 44 import java.util.Arrays; 45 46 /** 47 * A <code>ChoiceFormat</code> allows you to attach a format to a range of numbers. 48 * It is generally used in a <code>MessageFormat</code> for handling plurals. 49 * The choice is specified with an ascending list of doubles, where each item 50 * specifies a half-open interval up to the next item: 51 * <blockquote> 52 * <pre> 53 * X matches j if and only if limit[j] ≤ X < limit[j+1] 54 * </pre> 55 * </blockquote> 56 * If there is no match, then either the first or last index is used, depending 57 * on whether the number (X) is too low or too high. If the limit array is not 58 * in ascending order, the results of formatting will be incorrect. ChoiceFormat 59 * also accepts <code>\u221E</code> as equivalent to infinity(INF). 60 * 61 * <p> 62 * <strong>Note:</strong> 63 * <code>ChoiceFormat</code> differs from the other <code>Format</code> 64 * classes in that you create a <code>ChoiceFormat</code> object with a 65 * constructor (not with a <code>getInstance</code> style factory 66 * method). The factory methods aren't necessary because <code>ChoiceFormat</code> 67 * doesn't require any complex setup for a given locale. In fact, 68 * <code>ChoiceFormat</code> doesn't implement any locale specific behavior. 69 * 70 * <p> 71 * When creating a <code>ChoiceFormat</code>, you must specify an array of formats 72 * and an array of limits. The length of these arrays must be the same. 73 * For example, 74 * <ul> 75 * <li> 76 * <em>limits</em> = {1,2,3,4,5,6,7}<br> 77 * <em>formats</em> = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"} 78 * <li> 79 * <em>limits</em> = {0, 1, ChoiceFormat.nextDouble(1)}<br> 80 * <em>formats</em> = {"no files", "one file", "many files"}<br> 81 * (<code>nextDouble</code> can be used to get the next higher double, to 82 * make the half-open interval.) 83 * </ul> 84 * 85 * <p> 86 * Here is a simple example that shows formatting and parsing: 87 * <blockquote> 88 * <pre>{@code 89 * double[] limits = {1,2,3,4,5,6,7}; 90 * String[] dayOfWeekNames = {"Sun","Mon","Tue","Wed","Thur","Fri","Sat"}; 91 * ChoiceFormat form = new ChoiceFormat(limits, dayOfWeekNames); 92 * ParsePosition status = new ParsePosition(0); 93 * for (double i = 0.0; i <= 8.0; ++i) { 94 * status.setIndex(0); 95 * System.out.println(i + " -> " + form.format(i) + " -> " 96 * + form.parse(form.format(i),status)); 97 * } 98 * }</pre> 99 * </blockquote> 100 * Here is a more complex example, with a pattern format: 101 * <blockquote> 102 * <pre>{@code 103 * double[] filelimits = {0,1,2}; 104 * String[] filepart = {"are no files","is one file","are {2} files"}; 105 * ChoiceFormat fileform = new ChoiceFormat(filelimits, filepart); 106 * Format[] testFormats = {fileform, null, NumberFormat.getInstance()}; 107 * MessageFormat pattform = new MessageFormat("There {0} on {1}"); 108 * pattform.setFormats(testFormats); 109 * Object[] testArgs = {null, "ADisk", null}; 110 * for (int i = 0; i < 4; ++i) { 111 * testArgs[0] = new Integer(i); 112 * testArgs[2] = testArgs[0]; 113 * System.out.println(pattform.format(testArgs)); 114 * } 115 * }</pre> 116 * </blockquote> 117 * <p> 118 * Specifying a pattern for ChoiceFormat objects is fairly straightforward. 119 * For example: 120 * <blockquote> 121 * <pre>{@code 122 * ChoiceFormat fmt = new ChoiceFormat( 123 * "-1#is negative| 0#is zero or fraction | 1#is one |1.0<is 1+ |2#is two |2<is more than 2."); 124 * System.out.println("Formatter Pattern : " + fmt.toPattern()); 125 * 126 * System.out.println("Format with -INF : " + fmt.format(Double.NEGATIVE_INFINITY)); 127 * System.out.println("Format with -1.0 : " + fmt.format(-1.0)); 128 * System.out.println("Format with 0 : " + fmt.format(0)); 129 * System.out.println("Format with 0.9 : " + fmt.format(0.9)); 130 * System.out.println("Format with 1.0 : " + fmt.format(1)); 131 * System.out.println("Format with 1.5 : " + fmt.format(1.5)); 132 * System.out.println("Format with 2 : " + fmt.format(2)); 133 * System.out.println("Format with 2.1 : " + fmt.format(2.1)); 134 * System.out.println("Format with NaN : " + fmt.format(Double.NaN)); 135 * System.out.println("Format with +INF : " + fmt.format(Double.POSITIVE_INFINITY)); 136 * }</pre> 137 * </blockquote> 138 * And the output result would be like the following: 139 * <blockquote> 140 * <pre>{@code 141 * Format with -INF : is negative 142 * Format with -1.0 : is negative 143 * Format with 0 : is zero or fraction 144 * Format with 0.9 : is zero or fraction 145 * Format with 1.0 : is one 146 * Format with 1.5 : is 1+ 147 * Format with 2 : is two 148 * Format with 2.1 : is more than 2. 149 * Format with NaN : is negative 150 * Format with +INF : is more than 2. 151 * }</pre> 152 * </blockquote> 153 * 154 * <h3><a name="synchronization">Synchronization</a></h3> 155 * 156 * <p> 157 * Choice formats are not synchronized. 158 * It is recommended to create separate format instances for each thread. 159 * If multiple threads access a format concurrently, it must be synchronized 160 * externally. 161 * 162 * 163 * @see DecimalFormat 164 * @see MessageFormat 165 * @author Mark Davis 166 */ 167 public class ChoiceFormat extends NumberFormat { 168 169 // Proclaim serial compatibility with 1.1 FCS 170 private static final long serialVersionUID = 1795184449645032964L; 171 172 /** 173 * Sets the pattern. 174 * @param newPattern See the class description. 175 */ applyPattern(String newPattern)176 public void applyPattern(String newPattern) { 177 StringBuffer[] segments = new StringBuffer[2]; 178 for (int i = 0; i < segments.length; ++i) { 179 segments[i] = new StringBuffer(); 180 } 181 double[] newChoiceLimits = new double[30]; 182 String[] newChoiceFormats = new String[30]; 183 int count = 0; 184 int part = 0; 185 double startValue = 0; 186 double oldStartValue = Double.NaN; 187 boolean inQuote = false; 188 for (int i = 0; i < newPattern.length(); ++i) { 189 char ch = newPattern.charAt(i); 190 if (ch=='\'') { 191 // Check for "''" indicating a literal quote 192 if ((i+1)<newPattern.length() && newPattern.charAt(i+1)==ch) { 193 segments[part].append(ch); 194 ++i; 195 } else { 196 inQuote = !inQuote; 197 } 198 } else if (inQuote) { 199 segments[part].append(ch); 200 } else if (ch == '<' || ch == '#' || ch == '\u2264') { 201 if (segments[0].length() == 0) { 202 throw new IllegalArgumentException(); 203 } 204 try { 205 String tempBuffer = segments[0].toString(); 206 if (tempBuffer.equals("\u221E")) { 207 startValue = Double.POSITIVE_INFINITY; 208 } else if (tempBuffer.equals("-\u221E")) { 209 startValue = Double.NEGATIVE_INFINITY; 210 } else { 211 startValue = Double.parseDouble(segments[0].toString()); 212 } 213 } catch (Exception e) { 214 throw new IllegalArgumentException(); 215 } 216 if (ch == '<' && startValue != Double.POSITIVE_INFINITY && 217 startValue != Double.NEGATIVE_INFINITY) { 218 startValue = nextDouble(startValue); 219 } 220 if (startValue <= oldStartValue) { 221 throw new IllegalArgumentException(); 222 } 223 segments[0].setLength(0); 224 part = 1; 225 } else if (ch == '|') { 226 if (count == newChoiceLimits.length) { 227 newChoiceLimits = doubleArraySize(newChoiceLimits); 228 newChoiceFormats = doubleArraySize(newChoiceFormats); 229 } 230 newChoiceLimits[count] = startValue; 231 newChoiceFormats[count] = segments[1].toString(); 232 ++count; 233 oldStartValue = startValue; 234 segments[1].setLength(0); 235 part = 0; 236 } else { 237 segments[part].append(ch); 238 } 239 } 240 // clean up last one 241 if (part == 1) { 242 if (count == newChoiceLimits.length) { 243 newChoiceLimits = doubleArraySize(newChoiceLimits); 244 newChoiceFormats = doubleArraySize(newChoiceFormats); 245 } 246 newChoiceLimits[count] = startValue; 247 newChoiceFormats[count] = segments[1].toString(); 248 ++count; 249 } 250 choiceLimits = new double[count]; 251 System.arraycopy(newChoiceLimits, 0, choiceLimits, 0, count); 252 choiceFormats = new String[count]; 253 System.arraycopy(newChoiceFormats, 0, choiceFormats, 0, count); 254 } 255 256 /** 257 * Gets the pattern. 258 * 259 * @return the pattern string 260 */ toPattern()261 public String toPattern() { 262 StringBuffer result = new StringBuffer(); 263 for (int i = 0; i < choiceLimits.length; ++i) { 264 if (i != 0) { 265 result.append('|'); 266 } 267 // choose based upon which has less precision 268 // approximate that by choosing the closest one to an integer. 269 // could do better, but it's not worth it. 270 double less = previousDouble(choiceLimits[i]); 271 double tryLessOrEqual = Math.abs(Math.IEEEremainder(choiceLimits[i], 1.0d)); 272 double tryLess = Math.abs(Math.IEEEremainder(less, 1.0d)); 273 274 if (tryLessOrEqual < tryLess) { 275 result.append(""+choiceLimits[i]); 276 result.append('#'); 277 } else { 278 if (choiceLimits[i] == Double.POSITIVE_INFINITY) { 279 result.append("\u221E"); 280 } else if (choiceLimits[i] == Double.NEGATIVE_INFINITY) { 281 result.append("-\u221E"); 282 } else { 283 result.append(""+less); 284 } 285 result.append('<'); 286 } 287 // Append choiceFormats[i], using quotes if there are special characters. 288 // Single quotes themselves must be escaped in either case. 289 String text = choiceFormats[i]; 290 boolean needQuote = text.indexOf('<') >= 0 291 || text.indexOf('#') >= 0 292 || text.indexOf('\u2264') >= 0 293 || text.indexOf('|') >= 0; 294 if (needQuote) result.append('\''); 295 if (text.indexOf('\'') < 0) result.append(text); 296 else { 297 for (int j=0; j<text.length(); ++j) { 298 char c = text.charAt(j); 299 result.append(c); 300 if (c == '\'') result.append(c); 301 } 302 } 303 if (needQuote) result.append('\''); 304 } 305 return result.toString(); 306 } 307 308 /** 309 * Constructs with limits and corresponding formats based on the pattern. 310 * 311 * @param newPattern the new pattern string 312 * @see #applyPattern 313 */ ChoiceFormat(String newPattern)314 public ChoiceFormat(String newPattern) { 315 applyPattern(newPattern); 316 } 317 318 /** 319 * Constructs with the limits and the corresponding formats. 320 * 321 * @param limits limits in ascending order 322 * @param formats corresponding format strings 323 * @see #setChoices 324 */ ChoiceFormat(double[] limits, String[] formats)325 public ChoiceFormat(double[] limits, String[] formats) { 326 setChoices(limits, formats); 327 } 328 329 /** 330 * Set the choices to be used in formatting. 331 * @param limits contains the top value that you want 332 * parsed with that format, and should be in ascending sorted order. When 333 * formatting X, the choice will be the i, where 334 * limit[i] ≤ X {@literal <} limit[i+1]. 335 * If the limit array is not in ascending order, the results of formatting 336 * will be incorrect. 337 * @param formats are the formats you want to use for each limit. 338 * They can be either Format objects or Strings. 339 * When formatting with object Y, 340 * if the object is a NumberFormat, then ((NumberFormat) Y).format(X) 341 * is called. Otherwise Y.toString() is called. 342 */ setChoices(double[] limits, String formats[])343 public void setChoices(double[] limits, String formats[]) { 344 if (limits.length != formats.length) { 345 throw new IllegalArgumentException( 346 "Array and limit arrays must be of the same length."); 347 } 348 choiceLimits = Arrays.copyOf(limits, limits.length); 349 choiceFormats = Arrays.copyOf(formats, formats.length); 350 } 351 352 /** 353 * @return a copy of the {@code double[]} array supplied to the constructor or the most recent 354 * call to {@link #setChoices(double[], String[])}. 355 */ getLimits()356 public double[] getLimits() { 357 double[] newLimits = Arrays.copyOf(choiceLimits, choiceLimits.length); 358 return newLimits; 359 } 360 361 /** 362 * @return a copy of the {@code String[]} array supplied to the constructor or the most recent 363 * call to {@link #setChoices(double[], String[])}. 364 */ getFormats()365 public Object[] getFormats() { 366 Object[] newFormats = Arrays.copyOf(choiceFormats, choiceFormats.length); 367 return newFormats; 368 } 369 370 // Overrides 371 372 /** 373 * Specialization of format. This method really calls 374 * <code>format(double, StringBuffer, FieldPosition)</code> 375 * thus the range of longs that are supported is only equal to 376 * the range that can be stored by double. This will never be 377 * a practical limitation. 378 */ format(long number, StringBuffer toAppendTo, FieldPosition status)379 public StringBuffer format(long number, StringBuffer toAppendTo, 380 FieldPosition status) { 381 return format((double)number, toAppendTo, status); 382 } 383 384 /** 385 * Returns pattern with formatted double. 386 * @param number number to be formatted and substituted. 387 * @param toAppendTo where text is appended. 388 * @param status ignore no useful status is returned. 389 */ format(double number, StringBuffer toAppendTo, FieldPosition status)390 public StringBuffer format(double number, StringBuffer toAppendTo, 391 FieldPosition status) { 392 // find the number 393 int i; 394 for (i = 0; i < choiceLimits.length; ++i) { 395 if (!(number >= choiceLimits[i])) { 396 // same as number < choiceLimits, except catchs NaN 397 break; 398 } 399 } 400 --i; 401 if (i < 0) i = 0; 402 // return either a formatted number, or a string 403 return toAppendTo.append(choiceFormats[i]); 404 } 405 406 /** 407 * Parses a Number from the input text. 408 * @param text the source text. 409 * @param status an input-output parameter. On input, the 410 * status.index field indicates the first character of the 411 * source text that should be parsed. On exit, if no error 412 * occurred, status.index is set to the first unparsed character 413 * in the source text. On exit, if an error did occur, 414 * status.index is unchanged and status.errorIndex is set to the 415 * first index of the character that caused the parse to fail. 416 * @return A Number representing the value of the number parsed. 417 */ parse(String text, ParsePosition status)418 public Number parse(String text, ParsePosition status) { 419 // find the best number (defined as the one with the longest parse) 420 int start = status.index; 421 int furthest = start; 422 double bestNumber = Double.NaN; 423 double tempNumber = 0.0; 424 for (int i = 0; i < choiceFormats.length; ++i) { 425 String tempString = choiceFormats[i]; 426 if (text.regionMatches(start, tempString, 0, tempString.length())) { 427 status.index = start + tempString.length(); 428 tempNumber = choiceLimits[i]; 429 if (status.index > furthest) { 430 furthest = status.index; 431 bestNumber = tempNumber; 432 if (furthest == text.length()) break; 433 } 434 } 435 } 436 status.index = furthest; 437 if (status.index == start) { 438 status.errorIndex = furthest; 439 } 440 return new Double(bestNumber); 441 } 442 443 /** 444 * Finds the least double greater than {@code d}. 445 * If {@code NaN}, returns same value. 446 * <p>Used to make half-open intervals. 447 * 448 * @param d the reference value 449 * @return the least double value greather than {@code d} 450 * @see #previousDouble 451 */ nextDouble(double d)452 public static final double nextDouble (double d) { 453 return nextDouble(d,true); 454 } 455 456 /** 457 * Finds the greatest double less than {@code d}. 458 * If {@code NaN}, returns same value. 459 * 460 * @param d the reference value 461 * @return the greatest double value less than {@code d} 462 * @see #nextDouble 463 */ previousDouble(double d)464 public static final double previousDouble (double d) { 465 return nextDouble(d,false); 466 } 467 468 /** 469 * Overrides Cloneable 470 */ clone()471 public Object clone() 472 { 473 ChoiceFormat other = (ChoiceFormat) super.clone(); 474 // for primitives or immutables, shallow clone is enough 475 other.choiceLimits = choiceLimits.clone(); 476 other.choiceFormats = choiceFormats.clone(); 477 return other; 478 } 479 480 /** 481 * Generates a hash code for the message format object. 482 */ hashCode()483 public int hashCode() { 484 int result = choiceLimits.length; 485 if (choiceFormats.length > 0) { 486 // enough for reasonable distribution 487 result ^= choiceFormats[choiceFormats.length-1].hashCode(); 488 } 489 return result; 490 } 491 492 /** 493 * Equality comparision between two 494 */ equals(Object obj)495 public boolean equals(Object obj) { 496 if (obj == null) return false; 497 if (this == obj) // quick check 498 return true; 499 if (getClass() != obj.getClass()) 500 return false; 501 ChoiceFormat other = (ChoiceFormat) obj; 502 return (Arrays.equals(choiceLimits, other.choiceLimits) 503 && Arrays.equals(choiceFormats, other.choiceFormats)); 504 } 505 506 /** 507 * After reading an object from the input stream, do a simple verification 508 * to maintain class invariants. 509 * @throws InvalidObjectException if the objects read from the stream is invalid. 510 */ readObject(ObjectInputStream in)511 private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException { 512 in.defaultReadObject(); 513 if (choiceLimits.length != choiceFormats.length) { 514 throw new InvalidObjectException( 515 "limits and format arrays of different length."); 516 } 517 } 518 519 // ===============privates=========================== 520 521 /** 522 * A list of lower bounds for the choices. The formatter will return 523 * <code>choiceFormats[i]</code> if the number being formatted is greater than or equal to 524 * <code>choiceLimits[i]</code> and less than <code>choiceLimits[i+1]</code>. 525 * @serial 526 */ 527 private double[] choiceLimits; 528 529 /** 530 * A list of choice strings. The formatter will return 531 * <code>choiceFormats[i]</code> if the number being formatted is greater than or equal to 532 * <code>choiceLimits[i]</code> and less than <code>choiceLimits[i+1]</code>. 533 * @serial 534 */ 535 private String[] choiceFormats; 536 537 /* 538 static final long SIGN = 0x8000000000000000L; 539 static final long EXPONENT = 0x7FF0000000000000L; 540 static final long SIGNIFICAND = 0x000FFFFFFFFFFFFFL; 541 542 private static double nextDouble (double d, boolean positive) { 543 if (Double.isNaN(d) || Double.isInfinite(d)) { 544 return d; 545 } 546 long bits = Double.doubleToLongBits(d); 547 long significand = bits & SIGNIFICAND; 548 if (bits < 0) { 549 significand |= (SIGN | EXPONENT); 550 } 551 long exponent = bits & EXPONENT; 552 if (positive) { 553 significand += 1; 554 // FIXME fix overflow & underflow 555 } else { 556 significand -= 1; 557 // FIXME fix overflow & underflow 558 } 559 bits = exponent | (significand & ~EXPONENT); 560 return Double.longBitsToDouble(bits); 561 } 562 */ 563 564 static final long SIGN = 0x8000000000000000L; 565 static final long EXPONENT = 0x7FF0000000000000L; 566 static final long POSITIVEINFINITY = 0x7FF0000000000000L; 567 568 /** 569 * Finds the least double greater than {@code d} (if {@code positive} is 570 * {@code true}), or the greatest double less than {@code d} (if 571 * {@code positive} is {@code false}). 572 * If {@code NaN}, returns same value. 573 * 574 * Does not affect floating-point flags, 575 * provided these member functions do not: 576 * Double.longBitsToDouble(long) 577 * Double.doubleToLongBits(double) 578 * Double.isNaN(double) 579 * 580 * @param d the reference value 581 * @param positive {@code true} if the least double is desired; 582 * {@code false} otherwise 583 * @return the least or greater double value 584 */ nextDouble(double d, boolean positive)585 public static double nextDouble (double d, boolean positive) { 586 587 /* filter out NaN's */ 588 if (Double.isNaN(d)) { 589 return d; 590 } 591 592 /* zero's are also a special case */ 593 if (d == 0.0) { 594 double smallestPositiveDouble = Double.longBitsToDouble(1L); 595 if (positive) { 596 return smallestPositiveDouble; 597 } else { 598 return -smallestPositiveDouble; 599 } 600 } 601 602 /* if entering here, d is a nonzero value */ 603 604 /* hold all bits in a long for later use */ 605 long bits = Double.doubleToLongBits(d); 606 607 /* strip off the sign bit */ 608 long magnitude = bits & ~SIGN; 609 610 /* if next double away from zero, increase magnitude */ 611 if ((bits > 0) == positive) { 612 if (magnitude != POSITIVEINFINITY) { 613 magnitude += 1; 614 } 615 } 616 /* else decrease magnitude */ 617 else { 618 magnitude -= 1; 619 } 620 621 /* restore sign bit and return */ 622 long signbit = bits & SIGN; 623 return Double.longBitsToDouble (magnitude | signbit); 624 } 625 doubleArraySize(double[] array)626 private static double[] doubleArraySize(double[] array) { 627 int oldSize = array.length; 628 double[] newArray = new double[oldSize * 2]; 629 System.arraycopy(array, 0, newArray, 0, oldSize); 630 return newArray; 631 } 632 doubleArraySize(String[] array)633 private String[] doubleArraySize(String[] array) { 634 int oldSize = array.length; 635 String[] newArray = new String[oldSize * 2]; 636 System.arraycopy(array, 0, newArray, 0, oldSize); 637 return newArray; 638 } 639 640 } 641