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My first initial commit with all of mine experimental changes.

Dmitry Kabak (userdima committed 13 years ago

Commit d37b88d1 parent 3f5b46618352 files · +2598093 −-8690Browse files

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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+}