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| 1 | /* | ||
| 2 | * Copyright (c) 1996, 2006, 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.math.BigDecimal; | ||
| 42 | import java.math.BigInteger; | ||
| 43 | import java.math.RoundingMode; | ||
| 44 | |||
| 45 | /** | ||
| 46 | * Digit List. Private to DecimalFormat. | ||
| 47 | * Handles the transcoding | ||
| 48 | * between numeric values and strings of characters. Only handles | ||
| 49 | * non-negative numbers. The division of labor between DigitList and | ||
| 50 | * DecimalFormat is that DigitList handles the radix 10 representation | ||
| 51 | * issues; DecimalFormat handles the locale-specific issues such as | ||
| 52 | * positive/negative, grouping, decimal point, currency, and so on. | ||
| 53 | * | ||
| 54 | * A DigitList is really a representation of a floating point value. | ||
| 55 | * It may be an integer value; we assume that a double has sufficient | ||
| 56 | * precision to represent all digits of a long. | ||
| 57 | * | ||
| 58 | * The DigitList representation consists of a string of characters, | ||
| 59 | * which are the digits radix 10, from '0' to '9'. It also has a radix | ||
| 60 | * 10 exponent associated with it. The value represented by a DigitList | ||
| 61 | * object can be computed by mulitplying the fraction f, where 0 <= f < 1, | ||
| 62 | * derived by placing all the digits of the list to the right of the | ||
| 63 | * decimal point, by 10^exponent. | ||
| 64 | * | ||
| 65 | * @see Locale | ||
| 66 | * @see Format | ||
| 67 | * @see NumberFormat | ||
| 68 | * @see DecimalFormat | ||
| 69 | * @see ChoiceFormat | ||
| 70 | * @see MessageFormat | ||
| 71 | * @author Mark Davis, Alan Liu | ||
| 72 | */ | ||
| 73 | final class DigitList implements Cloneable { | ||
| 74 | /** | ||
| 75 | * The maximum number of significant digits in an IEEE 754 double, that | ||
| 76 | * is, in a Java double. This must not be increased, or garbage digits | ||
| 77 | * will be generated, and should not be decreased, or accuracy will be lost. | ||
| 78 | */ | ||
| 79 | public static final int MAX_COUNT = 19; // == Long.toString(Long.MAX_VALUE).length() | ||
| 80 | |||
| 81 | /** | ||
| 82 | * These data members are intentionally public and can be set directly. | ||
| 83 | * | ||
| 84 | * The value represented is given by placing the decimal point before | ||
| 85 | * digits[decimalAt]. If decimalAt is < 0, then leading zeros between | ||
| 86 | * the decimal point and the first nonzero digit are implied. If decimalAt | ||
| 87 | * is > count, then trailing zeros between the digits[count-1] and the | ||
| 88 | * decimal point are implied. | ||
| 89 | * | ||
| 90 | * Equivalently, the represented value is given by f * 10^decimalAt. Here | ||
| 91 | * f is a value 0.1 <= f < 1 arrived at by placing the digits in Digits to | ||
| 92 | * the right of the decimal. | ||
| 93 | * | ||
| 94 | * DigitList is normalized, so if it is non-zero, figits[0] is non-zero. We | ||
| 95 | * don't allow denormalized numbers because our exponent is effectively of | ||
| 96 | * unlimited magnitude. The count value contains the number of significant | ||
| 97 | * digits present in digits[]. | ||
| 98 | * | ||
| 99 | * Zero is represented by any DigitList with count == 0 or with each digits[i] | ||
| 100 | * for all i <= count == '0'. | ||
| 101 | */ | ||
| 102 | public int decimalAt = 0; | ||
| 103 | public int count = 0; | ||
| 104 | public char[] digits = new char[MAX_COUNT]; | ||
| 105 | |||
| 106 | private char[] data; | ||
| 107 | private RoundingMode roundingMode = RoundingMode.HALF_EVEN; | ||
| 108 | private boolean isNegative = false; | ||
| 109 | |||
| 110 | /** | ||
| 111 | * Return true if the represented number is zero. | ||
| 112 | */ | ||
| 113 | boolean isZero() { | ||
| 114 | for (int i=0; i < count; ++i) { | ||
| 115 | if (digits[i] != '0') { | ||
| 116 | return false; | ||
| 117 | } | ||
| 118 | } | ||
| 119 | return true; | ||
| 120 | } | ||
| 121 | |||
| 122 | /** | ||
| 123 | * Set the rounding mode | ||
| 124 | */ | ||
| 125 | void setRoundingMode(RoundingMode r) { | ||
| 126 | roundingMode = r; | ||
| 127 | } | ||
| 128 | |||
| 129 | /** | ||
| 130 | * Clears out the digits. | ||
| 131 | * Use before appending them. | ||
| 132 | * Typically, you set a series of digits with append, then at the point | ||
| 133 | * you hit the decimal point, you set myDigitList.decimalAt = myDigitList.count; | ||
| 134 | * then go on appending digits. | ||
| 135 | */ | ||
| 136 | public void clear () { | ||
| 137 | decimalAt = 0; | ||
| 138 | count = 0; | ||
| 139 | } | ||
| 140 | |||
| 141 | /** | ||
| 142 | * Appends a digit to the list, extending the list when necessary. | ||
| 143 | */ | ||
| 144 | public void append(char digit) { | ||
| 145 | if (count == digits.length) { | ||
| 146 | char[] data = new char[count + 100]; | ||
| 147 | System.arraycopy(digits, 0, data, 0, count); | ||
| 148 | digits = data; | ||
| 149 | } | ||
| 150 | digits[count++] = digit; | ||
| 151 | } | ||
| 152 | |||
| 153 | /** | ||
| 154 | * Utility routine to get the value of the digit list | ||
| 155 | * If (count == 0) this throws a NumberFormatException, which | ||
| 156 | * mimics Long.parseLong(). | ||
| 157 | */ | ||
| 158 | public final double getDouble() { | ||
| 159 | if (count == 0) { | ||
| 160 | return 0.0; | ||
| 161 | } | ||
| 162 | |||
| 163 | StringBuffer temp = getStringBuffer(); | ||
| 164 | temp.append('.'); | ||
| 165 | temp.append(digits, 0, count); | ||
| 166 | temp.append('E'); | ||
| 167 | temp.append(decimalAt); | ||
| 168 | return Double.parseDouble(temp.toString()); | ||
| 169 | } | ||
| 170 | |||
| 171 | /** | ||
| 172 | * Utility routine to get the value of the digit list. | ||
| 173 | * If (count == 0) this returns 0, unlike Long.parseLong(). | ||
| 174 | */ | ||
| 175 | public final long getLong() { | ||
| 176 | // for now, simple implementation; later, do proper IEEE native stuff | ||
| 177 | |||
| 178 | if (count == 0) { | ||
| 179 | return 0; | ||
| 180 | } | ||
| 181 | |||
| 182 | // We have to check for this, because this is the one NEGATIVE value | ||
| 183 | // we represent. If we tried to just pass the digits off to parseLong, | ||
| 184 | // we'd get a parse failure. | ||
| 185 | if (isLongMIN_VALUE()) { | ||
| 186 | return Long.MIN_VALUE; | ||
| 187 | } | ||
| 188 | |||
| 189 | StringBuffer temp = getStringBuffer(); | ||
| 190 | temp.append(digits, 0, count); | ||
| 191 | for (int i = count; i < decimalAt; ++i) { | ||
| 192 | temp.append('0'); | ||
| 193 | } | ||
| 194 | return Long.parseLong(temp.toString()); | ||
| 195 | } | ||
| 196 | |||
| 197 | public final BigDecimal getBigDecimal() { | ||
| 198 | if (count == 0) { | ||
| 199 | if (decimalAt == 0) { | ||
| 200 | return BigDecimal.ZERO; | ||
| 201 | } else { | ||
| 202 | return new BigDecimal("0E" + decimalAt); | ||
| 203 | } | ||
| 204 | } | ||
| 205 | |||
| 206 | if (decimalAt == count) { | ||
| 207 | return new BigDecimal(digits, 0, count); | ||
| 208 | } else { | ||
| 209 | return new BigDecimal(digits, 0, count).scaleByPowerOfTen(decimalAt - count); | ||
| 210 | } | ||
| 211 | } | ||
| 212 | |||
| 213 | /** | ||
| 214 | * Return true if the number represented by this object can fit into | ||
| 215 | * a long. | ||
| 216 | * @param isPositive true if this number should be regarded as positive | ||
| 217 | * @param ignoreNegativeZero true if -0 should be regarded as identical to | ||
| 218 | * +0; otherwise they are considered distinct | ||
| 219 | * @return true if this number fits into a Java long | ||
| 220 | */ | ||
| 221 | boolean fitsIntoLong(boolean isPositive, boolean ignoreNegativeZero) { | ||
| 222 | // Figure out if the result will fit in a long. We have to | ||
| 223 | // first look for nonzero digits after the decimal point; | ||
| 224 | // then check the size. If the digit count is 18 or less, then | ||
| 225 | // the value can definitely be represented as a long. If it is 19 | ||
| 226 | // then it may be too large. | ||
| 227 | |||
| 228 | // Trim trailing zeros. This does not change the represented value. | ||
| 229 | while (count > 0 && digits[count - 1] == '0') { | ||
| 230 | --count; | ||
| 231 | } | ||
| 232 | |||
| 233 | if (count == 0) { | ||
| 234 | // Positive zero fits into a long, but negative zero can only | ||
| 235 | // be represented as a double. - bug 4162852 | ||
| 236 | return isPositive || ignoreNegativeZero; | ||
| 237 | } | ||
| 238 | |||
| 239 | if (decimalAt < count || decimalAt > MAX_COUNT) { | ||
| 240 | return false; | ||
| 241 | } | ||
| 242 | |||
| 243 | if (decimalAt < MAX_COUNT) return true; | ||
| 244 | |||
| 245 | // At this point we have decimalAt == count, and count == MAX_COUNT. | ||
| 246 | // The number will overflow if it is larger than 9223372036854775807 | ||
| 247 | // or smaller than -9223372036854775808. | ||
| 248 | for (int i=0; i<count; ++i) { | ||
| 249 | char dig = digits[i], max = LONG_MIN_REP[i]; | ||
| 250 | if (dig > max) return false; | ||
| 251 | if (dig < max) return true; | ||
| 252 | } | ||
| 253 | |||
| 254 | // At this point the first count digits match. If decimalAt is less | ||
| 255 | // than count, then the remaining digits are zero, and we return true. | ||
| 256 | if (count < decimalAt) return true; | ||
| 257 | |||
| 258 | // Now we have a representation of Long.MIN_VALUE, without the leading | ||
| 259 | // negative sign. If this represents a positive value, then it does | ||
| 260 | // not fit; otherwise it fits. | ||
| 261 | return !isPositive; | ||
| 262 | } | ||
| 263 | |||
| 264 | /** | ||
| 265 | * Set the digit list to a representation of the given double value. | ||
| 266 | * This method supports fixed-point notation. | ||
| 267 | * @param isNegative Boolean value indicating whether the number is negative. | ||
| 268 | * @param source Value to be converted; must not be Inf, -Inf, Nan, | ||
| 269 | * or a value <= 0. | ||
| 270 | * @param maximumFractionDigits The most fractional digits which should | ||
| 271 | * be converted. | ||
| 272 | */ | ||
| 273 | public final void set(boolean isNegative, double source, int maximumFractionDigits) { | ||
| 274 | set(isNegative, source, maximumFractionDigits, true); | ||
| 275 | } | ||
| 276 | |||
| 277 | /** | ||
| 278 | * Set the digit list to a representation of the given double value. | ||
| 279 | * This method supports both fixed-point and exponential notation. | ||
| 280 | * @param isNegative Boolean value indicating whether the number is negative. | ||
| 281 | * @param source Value to be converted; must not be Inf, -Inf, Nan, | ||
| 282 | * or a value <= 0. | ||
| 283 | * @param maximumDigits The most fractional or total digits which should | ||
| 284 | * be converted. | ||
| 285 | * @param fixedPoint If true, then maximumDigits is the maximum | ||
| 286 | * fractional digits to be converted. If false, total digits. | ||
| 287 | */ | ||
| 288 | final void set(boolean isNegative, double source, int maximumDigits, boolean fixedPoint) { | ||
| 289 | set(isNegative, Double.toString(source), maximumDigits, fixedPoint); | ||
| 290 | } | ||
| 291 | |||
| 292 | /** | ||
| 293 | * Generate a representation of the form DDDDD, DDDDD.DDDDD, or | ||
| 294 | * DDDDDE+/-DDDDD. | ||
| 295 | */ | ||
| 296 | final void set(boolean isNegative, String s, int maximumDigits, boolean fixedPoint) { | ||
| 297 | this.isNegative = isNegative; | ||
| 298 | int len = s.length(); | ||
| 299 | char[] source = getDataChars(len); | ||
| 300 | s.getChars(0, len, source, 0); | ||
| 301 | |||
| 302 | decimalAt = -1; | ||
| 303 | count = 0; | ||
| 304 | int exponent = 0; | ||
| 305 | // Number of zeros between decimal point and first non-zero digit after | ||
| 306 | // decimal point, for numbers < 1. | ||
| 307 | int leadingZerosAfterDecimal = 0; | ||
| 308 | boolean nonZeroDigitSeen = false; | ||
| 309 | |||
| 310 | for (int i = 0; i < len; ) { | ||
| 311 | char c = source[i++]; | ||
| 312 | if (c == '.') { | ||
| 313 | decimalAt = count; | ||
| 314 | } else if (c == 'e' || c == 'E') { | ||
| 315 | exponent = parseInt(source, i, len); | ||
| 316 | break; | ||
| 317 | } else { | ||
| 318 | if (!nonZeroDigitSeen) { | ||
| 319 | nonZeroDigitSeen = (c != '0'); | ||
| 320 | if (!nonZeroDigitSeen && decimalAt != -1) | ||
| 321 | ++leadingZerosAfterDecimal; | ||
| 322 | } | ||
| 323 | if (nonZeroDigitSeen) { | ||
| 324 | digits[count++] = c; | ||
| 325 | } | ||
| 326 | } | ||
| 327 | } | ||
| 328 | if (decimalAt == -1) { | ||
| 329 | decimalAt = count; | ||
| 330 | } | ||
| 331 | if (nonZeroDigitSeen) { | ||
| 332 | decimalAt += exponent - leadingZerosAfterDecimal; | ||
| 333 | } | ||
| 334 | |||
| 335 | if (fixedPoint) { | ||
| 336 | // The negative of the exponent represents the number of leading | ||
| 337 | // zeros between the decimal and the first non-zero digit, for | ||
| 338 | // a value < 0.1 (e.g., for 0.00123, -decimalAt == 2). If this | ||
| 339 | // is more than the maximum fraction digits, then we have an underflow | ||
| 340 | // for the printed representation. | ||
| 341 | if (-decimalAt > maximumDigits) { | ||
| 342 | // Handle an underflow to zero when we round something like | ||
| 343 | // 0.0009 to 2 fractional digits. | ||
| 344 | count = 0; | ||
| 345 | return; | ||
| 346 | } else if (-decimalAt == maximumDigits) { | ||
| 347 | // If we round 0.0009 to 3 fractional digits, then we have to | ||
| 348 | // create a new one digit in the least significant location. | ||
| 349 | if (shouldRoundUp(0)) { | ||
| 350 | count = 1; | ||
| 351 | ++decimalAt; | ||
| 352 | digits[0] = '1'; | ||
| 353 | } else { | ||
| 354 | count = 0; | ||
| 355 | } | ||
| 356 | return; | ||
| 357 | } | ||
| 358 | // else fall through | ||
| 359 | } | ||
| 360 | |||
| 361 | // Eliminate trailing zeros. | ||
| 362 | while (count > 1 && digits[count - 1] == '0') { | ||
| 363 | --count; | ||
| 364 | } | ||
| 365 | |||
| 366 | // Eliminate digits beyond maximum digits to be displayed. | ||
| 367 | // Round up if appropriate. | ||
| 368 | round(fixedPoint ? (maximumDigits + decimalAt) : maximumDigits); | ||
| 369 | } | ||
| 370 | |||
| 371 | /** | ||
| 372 | * Round the representation to the given number of digits. | ||
| 373 | * @param maximumDigits The maximum number of digits to be shown. | ||
| 374 | * Upon return, count will be less than or equal to maximumDigits. | ||
| 375 | */ | ||
| 376 | private final void round(int maximumDigits) { | ||
| 377 | // Eliminate digits beyond maximum digits to be displayed. | ||
| 378 | // Round up if appropriate. | ||
| 379 | if (maximumDigits >= 0 && maximumDigits < count) { | ||
| 380 | if (shouldRoundUp(maximumDigits)) { | ||
| 381 | // Rounding up involved incrementing digits from LSD to MSD. | ||
| 382 | // In most cases this is simple, but in a worst case situation | ||
| 383 | // (9999..99) we have to adjust the decimalAt value. | ||
| 384 | for (;;) { | ||
| 385 | --maximumDigits; | ||
| 386 | if (maximumDigits < 0) { | ||
| 387 | // We have all 9's, so we increment to a single digit | ||
| 388 | // of one and adjust the exponent. | ||
| 389 | digits[0] = '1'; | ||
| 390 | ++decimalAt; | ||
| 391 | maximumDigits = 0; // Adjust the count | ||
| 392 | break; | ||
| 393 | } | ||
| 394 | |||
| 395 | ++digits[maximumDigits]; | ||
| 396 | if (digits[maximumDigits] <= '9') break; | ||
| 397 | // digits[maximumDigits] = '0'; // Unnecessary since we'll truncate this | ||
| 398 | } | ||
| 399 | ++maximumDigits; // Increment for use as count | ||
| 400 | } | ||
| 401 | count = maximumDigits; | ||
| 402 | |||
| 403 | // Eliminate trailing zeros. | ||
| 404 | while (count > 1 && digits[count-1] == '0') { | ||
| 405 | --count; | ||
| 406 | } | ||
| 407 | } | ||
| 408 | } | ||
| 409 | |||
| 410 | |||
| 411 | /** | ||
| 412 | * Return true if truncating the representation to the given number | ||
| 413 | * of digits will result in an increment to the last digit. This | ||
| 414 | * method implements the rounding modes defined in the | ||
| 415 | * java.math.RoundingMode class. | ||
| 416 | * [bnf] | ||
| 417 | * @param maximumDigits the number of digits to keep, from 0 to | ||
| 418 | * <code>count-1</code>. If 0, then all digits are rounded away, and | ||
| 419 | * this method returns true if a one should be generated (e.g., formatting | ||
| 420 | * 0.09 with "#.#"). | ||
| 421 | * @exception ArithmeticException if rounding is needed with rounding | ||
| 422 | * mode being set to RoundingMode.UNNECESSARY | ||
| 423 | * @return true if digit <code>maximumDigits-1</code> should be | ||
| 424 | * incremented | ||
| 425 | */ | ||
| 426 | private boolean shouldRoundUp(int maximumDigits) { | ||
| 427 | if (maximumDigits < count) { | ||
| 428 | switch(roundingMode) { | ||
| 429 | case UP: | ||
| 430 | for (int i=maximumDigits; i<count; ++i) { | ||
| 431 | if (digits[i] != '0') { | ||
| 432 | return true; | ||
| 433 | } | ||
| 434 | } | ||
| 435 | break; | ||
| 436 | case DOWN: | ||
| 437 | break; | ||
| 438 | case CEILING: | ||
| 439 | for (int i=maximumDigits; i<count; ++i) { | ||
| 440 | if (digits[i] != '0') { | ||
| 441 | return !isNegative; | ||
| 442 | } | ||
| 443 | } | ||
| 444 | break; | ||
| 445 | case FLOOR: | ||
| 446 | for (int i=maximumDigits; i<count; ++i) { | ||
| 447 | if (digits[i] != '0') { | ||
| 448 | return isNegative; | ||
| 449 | } | ||
| 450 | } | ||
| 451 | break; | ||
| 452 | case HALF_UP: | ||
| 453 | if (digits[maximumDigits] >= '5') { | ||
| 454 | return true; | ||
| 455 | } | ||
| 456 | break; | ||
| 457 | case HALF_DOWN: | ||
| 458 | if (digits[maximumDigits] > '5') { | ||
| 459 | return true; | ||
| 460 | } else if (digits[maximumDigits] == '5' ) { | ||
| 461 | for (int i=maximumDigits+1; i<count; ++i) { | ||
| 462 | if (digits[i] != '0') { | ||
| 463 | return true; | ||
| 464 | } | ||
| 465 | } | ||
| 466 | } | ||
| 467 | break; | ||
| 468 | case HALF_EVEN: | ||
| 469 | // Implement IEEE half-even rounding | ||
| 470 | if (digits[maximumDigits] > '5') { | ||
| 471 | return true; | ||
| 472 | } else if (digits[maximumDigits] == '5' ) { | ||
| 473 | for (int i=maximumDigits+1; i<count; ++i) { | ||
| 474 | if (digits[i] != '0') { | ||
| 475 | return true; | ||
| 476 | } | ||
| 477 | } | ||
| 478 | return maximumDigits > 0 && (digits[maximumDigits-1] % 2 != 0); | ||
| 479 | } | ||
| 480 | break; | ||
| 481 | case UNNECESSARY: | ||
| 482 | for (int i=maximumDigits; i<count; ++i) { | ||
| 483 | if (digits[i] != '0') { | ||
| 484 | throw new ArithmeticException( | ||
| 485 | "Rounding needed with the rounding mode being set to RoundingMode.UNNECESSARY"); | ||
| 486 | } | ||
| 487 | } | ||
| 488 | break; | ||
| 489 | default: | ||
| 490 | assert false; | ||
| 491 | } | ||
| 492 | } | ||
| 493 | return false; | ||
| 494 | } | ||
| 495 | |||
| 496 | /** | ||
| 497 | * Utility routine to set the value of the digit list from a long | ||
| 498 | */ | ||
| 499 | public final void set(boolean isNegative, long source) { | ||
| 500 | set(isNegative, source, 0); | ||
| 501 | } | ||
| 502 | |||
| 503 | /** | ||
| 504 | * Set the digit list to a representation of the given long value. | ||
| 505 | * @param isNegative Boolean value indicating whether the number is negative. | ||
| 506 | * @param source Value to be converted; must be >= 0 or == | ||
| 507 | * Long.MIN_VALUE. | ||
| 508 | * @param maximumDigits The most digits which should be converted. | ||
| 509 | * If maximumDigits is lower than the number of significant digits | ||
| 510 | * in source, the representation will be rounded. Ignored if <= 0. | ||
| 511 | */ | ||
| 512 | public final void set(boolean isNegative, long source, int maximumDigits) { | ||
| 513 | this.isNegative = isNegative; | ||
| 514 | |||
| 515 | // This method does not expect a negative number. However, | ||
| 516 | // "source" can be a Long.MIN_VALUE (-9223372036854775808), | ||
| 517 | // if the number being formatted is a Long.MIN_VALUE. In that | ||
| 518 | // case, it will be formatted as -Long.MIN_VALUE, a number | ||
| 519 | // which is outside the legal range of a long, but which can | ||
| 520 | // be represented by DigitList. | ||
| 521 | if (source <= 0) { | ||
| 522 | if (source == Long.MIN_VALUE) { | ||
| 523 | decimalAt = count = MAX_COUNT; | ||
| 524 | System.arraycopy(LONG_MIN_REP, 0, digits, 0, count); | ||
| 525 | } else { | ||
| 526 | decimalAt = count = 0; // Values <= 0 format as zero | ||
| 527 | } | ||
| 528 | } else { | ||
| 529 | // Rewritten to improve performance. I used to call | ||
| 530 | // Long.toString(), which was about 4x slower than this code. | ||
| 531 | int left = MAX_COUNT; | ||
| 532 | int right; | ||
| 533 | while (source > 0) { | ||
| 534 | digits[--left] = (char)('0' + (source % 10)); | ||
| 535 | source /= 10; | ||
| 536 | } | ||
| 537 | decimalAt = MAX_COUNT - left; | ||
| 538 | // Don't copy trailing zeros. We are guaranteed that there is at | ||
| 539 | // least one non-zero digit, so we don't have to check lower bounds. | ||
| 540 | for (right = MAX_COUNT - 1; digits[right] == '0'; --right) | ||
| 541 | ; | ||
| 542 | count = right - left + 1; | ||
| 543 | System.arraycopy(digits, left, digits, 0, count); | ||
| 544 | } | ||
| 545 | if (maximumDigits > 0) round(maximumDigits); | ||
| 546 | } | ||
| 547 | |||
| 548 | /** | ||
| 549 | * Set the digit list to a representation of the given BigDecimal value. | ||
| 550 | * This method supports both fixed-point and exponential notation. | ||
| 551 | * @param isNegative Boolean value indicating whether the number is negative. | ||
| 552 | * @param source Value to be converted; must not be a value <= 0. | ||
| 553 | * @param maximumDigits The most fractional or total digits which should | ||
| 554 | * be converted. | ||
| 555 | * @param fixedPoint If true, then maximumDigits is the maximum | ||
| 556 | * fractional digits to be converted. If false, total digits. | ||
| 557 | */ | ||
| 558 | final void set(boolean isNegative, BigDecimal source, int maximumDigits, boolean fixedPoint) { | ||
| 559 | String s = source.toString(); | ||
| 560 | extendDigits(s.length()); | ||
| 561 | |||
| 562 | set(isNegative, s, maximumDigits, fixedPoint); | ||
| 563 | } | ||
| 564 | |||
| 565 | /** | ||
| 566 | * Set the digit list to a representation of the given BigInteger value. | ||
| 567 | * @param isNegative Boolean value indicating whether the number is negative. | ||
| 568 | * @param source Value to be converted; must be >= 0. | ||
| 569 | * @param maximumDigits The most digits which should be converted. | ||
| 570 | * If maximumDigits is lower than the number of significant digits | ||
| 571 | * in source, the representation will be rounded. Ignored if <= 0. | ||
| 572 | */ | ||
| 573 | final void set(boolean isNegative, BigInteger source, int maximumDigits) { | ||
| 574 | this.isNegative = isNegative; | ||
| 575 | String s = source.toString(); | ||
| 576 | int len = s.length(); | ||
| 577 | extendDigits(len); | ||
| 578 | s.getChars(0, len, digits, 0); | ||
| 579 | |||
| 580 | decimalAt = len; | ||
| 581 | int right; | ||
| 582 | for (right = len - 1; right >= 0 && digits[right] == '0'; --right) | ||
| 583 | ; | ||
| 584 | count = right + 1; | ||
| 585 | |||
| 586 | if (maximumDigits > 0) { | ||
| 587 | round(maximumDigits); | ||
| 588 | } | ||
| 589 | } | ||
| 590 | |||
| 591 | /** | ||
| 592 | * equality test between two digit lists. | ||
| 593 | */ | ||
| 594 | public boolean equals(Object obj) { | ||
| 595 | if (this == obj) // quick check | ||
| 596 | return true; | ||
| 597 | if (!(obj instanceof DigitList)) // (1) same object? | ||
| 598 | return false; | ||
| 599 | DigitList other = (DigitList) obj; | ||
| 600 | if (count != other.count || | ||
| 601 | decimalAt != other.decimalAt) | ||
| 602 | return false; | ||
| 603 | for (int i = 0; i < count; i++) | ||
| 604 | if (digits[i] != other.digits[i]) | ||
| 605 | return false; | ||
| 606 | return true; | ||
| 607 | } | ||
| 608 | |||
| 609 | /** | ||
| 610 | * Generates the hash code for the digit list. | ||
| 611 | */ | ||
| 612 | public int hashCode() { | ||
| 613 | int hashcode = decimalAt; | ||
| 614 | |||
| 615 | for (int i = 0; i < count; i++) { | ||
| 616 | hashcode = hashcode * 37 + digits[i]; | ||
| 617 | } | ||
| 618 | |||
| 619 | return hashcode; | ||
| 620 | } | ||
| 621 | |||
| 622 | /** | ||
| 623 | * Creates a copy of this object. | ||
| 624 | * @return a clone of this instance. | ||
| 625 | */ | ||
| 626 | public Object clone() { | ||
| 627 | try { | ||
| 628 | DigitList other = (DigitList) super.clone(); | ||
| 629 | char[] newDigits = new char[digits.length]; | ||
| 630 | System.arraycopy(digits, 0, newDigits, 0, digits.length); | ||
| 631 | other.digits = newDigits; | ||
| 632 | other.tempBuffer = null; | ||
| 633 | return other; | ||
| 634 | } catch (CloneNotSupportedException e) { | ||
| 635 | throw new InternalError(); | ||
| 636 | } | ||
| 637 | } | ||
| 638 | |||
| 639 | /** | ||
| 640 | * Returns true if this DigitList represents Long.MIN_VALUE; | ||
| 641 | * false, otherwise. This is required so that getLong() works. | ||
| 642 | */ | ||
| 643 | private boolean isLongMIN_VALUE() { | ||
| 644 | if (decimalAt != count || count != MAX_COUNT) { | ||
| 645 | return false; | ||
| 646 | } | ||
| 647 | |||
| 648 | for (int i = 0; i < count; ++i) { | ||
| 649 | if (digits[i] != LONG_MIN_REP[i]) return false; | ||
| 650 | } | ||
| 651 | |||
| 652 | return true; | ||
| 653 | } | ||
| 654 | |||
| 655 | private static final int parseInt(char[] str, int offset, int strLen) { | ||
| 656 | char c; | ||
| 657 | boolean positive = true; | ||
| 658 | if ((c = str[offset]) == '-') { | ||
| 659 | positive = false; | ||
| 660 | offset++; | ||
| 661 | } else if (c == '+') { | ||
| 662 | offset++; | ||
| 663 | } | ||
| 664 | |||
| 665 | int value = 0; | ||
| 666 | while (offset < strLen) { | ||
| 667 | c = str[offset++]; | ||
| 668 | if (c >= '0' && c <= '9') { | ||
| 669 | value = value * 10 + (c - '0'); | ||
| 670 | } else { | ||
| 671 | break; | ||
| 672 | } | ||
| 673 | } | ||
| 674 | return positive ? value : -value; | ||
| 675 | } | ||
| 676 | |||
| 677 | // The digit part of -9223372036854775808L | ||
| 678 | private static final char[] LONG_MIN_REP = "9223372036854775808".toCharArray(); | ||
| 679 | |||
| 680 | public String toString() { | ||
| 681 | if (isZero()) { | ||
| 682 | return "0"; | ||
| 683 | } | ||
| 684 | StringBuffer buf = getStringBuffer(); | ||
| 685 | buf.append("0."); | ||
| 686 | buf.append(digits, 0, count); | ||
| 687 | buf.append("x10^"); | ||
| 688 | buf.append(decimalAt); | ||
| 689 | return buf.toString(); | ||
| 690 | } | ||
| 691 | |||
| 692 | private StringBuffer tempBuffer; | ||
| 693 | |||
| 694 | private StringBuffer getStringBuffer() { | ||
| 695 | if (tempBuffer == null) { | ||
| 696 | tempBuffer = new StringBuffer(MAX_COUNT); | ||
| 697 | } else { | ||
| 698 | tempBuffer.setLength(0); | ||
| 699 | } | ||
| 700 | return tempBuffer; | ||
| 701 | } | ||
| 702 | |||
| 703 | private void extendDigits(int len) { | ||
| 704 | if (len > digits.length) { | ||
| 705 | digits = new char[len]; | ||
| 706 | } | ||
| 707 | } | ||
| 708 | |||
| 709 | private final char[] getDataChars(int length) { | ||
| 710 | if (data == null || data.length < length) { | ||
| 711 | data = new char[length]; | ||
| 712 | } | ||
| 713 | return data; | ||
| 714 | } | ||
| 715 | } | ||