Fix issue in DecimalFormat rounding.

When value near 1 (0.999...) is rounded to 1, exponent should be increased.
This fixes #557. Also reuse exponent/mantissa/sign analyzer
written for StringBuilder.append(double)
This commit is contained in:
Alexey Andreev 2021-02-27 22:07:00 +03:00
parent e4c808c324
commit 0ade0313ce
2 changed files with 83 additions and 124 deletions

View File

@ -19,6 +19,8 @@ import java.math.BigDecimal;
import java.math.BigInteger; import java.math.BigInteger;
import java.text.DecimalFormatSymbols; import java.text.DecimalFormatSymbols;
import java.util.Arrays; import java.util.Arrays;
import org.teavm.classlib.impl.text.DoubleAnalyzer;
import org.teavm.classlib.impl.text.FloatAnalyzer;
import org.teavm.classlib.impl.unicode.CLDRHelper; import org.teavm.classlib.impl.unicode.CLDRHelper;
import org.teavm.classlib.java.lang.TArithmeticException; import org.teavm.classlib.java.lang.TArithmeticException;
import org.teavm.classlib.java.lang.TDouble; import org.teavm.classlib.java.lang.TDouble;
@ -31,9 +33,6 @@ public class TDecimalFormat extends TNumberFormat {
1_0_0000_0000_0000_0000L, 1_00_0000_0000_0000_0000L }; 1_0_0000_0000_0000_0000L, 1_00_0000_0000_0000_0000L };
private static final int[] POW10_INT_ARRAY = { 1, 10, 100, 1000, 1_0000, 1_0_0000, 1_00_0000, private static final int[] POW10_INT_ARRAY = { 1, 10, 100, 1000, 1_0000, 1_0_0000, 1_00_0000,
1_000_0000, 1_0000_0000, 1_0_0000_0000 }; 1_000_0000, 1_0000_0000, 1_0_0000_0000 };
private static final double[] POW10_FRAC_ARRAY = { 1E1, 1E2, 1E4, 1E8, 1E16, 1E32, 1E64, 1E128, 1E256 };
private static final double[] POWM10_FRAC_ARRAY = { 1E-1, 1E-2, 1E-4, 1E-8, 1E-16, 1E-32, 1E-64, 1E-128, 1E-256 };
private static final int DOUBLE_MAX_EXPONENT = 308;
private static final long MAX_LONG_DIV_10 = Long.MAX_VALUE / 10; private static final long MAX_LONG_DIV_10 = Long.MAX_VALUE / 10;
TDecimalFormatSymbols symbols; TDecimalFormatSymbols symbols;
FormatField[] positivePrefix = {}; FormatField[] positivePrefix = {};
@ -550,28 +549,30 @@ public class TDecimalFormat extends TNumberFormat {
fieldsToText(value > 0 ? positivePrefix : negativePrefix, buffer).append(symbols.getInfinity()); fieldsToText(value > 0 ? positivePrefix : negativePrefix, buffer).append(symbols.getInfinity());
appendSuffix(value > 0, buffer); appendSuffix(value > 0, buffer);
} else { } else {
MantissaAndExponent me = getMantissaAndExponent(value); DoubleAnalyzer.Result analysisResult = Constants.doubleAnalysisResult;
DoubleAnalyzer.analyze(value, analysisResult);
if (exponentDigits > 0) { if (exponentDigits > 0) {
formatExponent(me.mantissa, me.exponent, buffer); formatExponent(analysisResult.mantissa, analysisResult.exponent, !analysisResult.sign, buffer);
} else { } else {
formatRegular(me.mantissa, me.exponent, buffer); formatRegular(analysisResult.mantissa, analysisResult.exponent, !analysisResult.sign, buffer);
} }
} }
return buffer; return buffer;
} }
private void formatExponent(long value, StringBuffer buffer) { private void formatExponent(long value, StringBuffer buffer) {
int exponent = fastLn10(Math.abs(value)); long absValue = Math.abs(value);
formatExponent(value, exponent, buffer); int exponent = fastLn10(absValue);
formatExponent(absValue, exponent, value >= 0, buffer);
} }
private void formatRegular(long value, StringBuffer buffer) { private void formatRegular(long value, StringBuffer buffer) {
int exponent = fastLn10(Math.abs(value)); long absValue = Math.abs(value);
formatRegular(value, exponent, buffer); int exponent = fastLn10(absValue);
formatRegular(absValue, exponent, value >= 0, buffer);
} }
private void formatExponent(long mantissa, int exponent, StringBuffer buffer) { private void formatExponent(long mantissa, int exponent, boolean sign, StringBuffer buffer) {
boolean positive = mantissa >= 0;
int visibleExponent = fastLn10(mantissa); int visibleExponent = fastLn10(mantissa);
int mantissaLength = visibleExponent + 1; int mantissaLength = visibleExponent + 1;
@ -580,12 +581,11 @@ public class TDecimalFormat extends TNumberFormat {
int tenMultiplier = POW10_INT_ARRAY[multiplierDigits]; int tenMultiplier = POW10_INT_ARRAY[multiplierDigits];
if (tenMultiplier == multiplier) { if (tenMultiplier == multiplier) {
exponent += multiplierDigits; exponent += multiplierDigits;
} else if (mantissa >= Long.MAX_VALUE / multiplier || mantissa <= Long.MIN_VALUE / multiplier) { } else if (mantissa >= Long.MAX_VALUE / multiplier) {
formatExponent(new BigDecimal(BigInteger.valueOf(mantissa), visibleExponent - exponent), buffer); formatExponent(new BigDecimal(BigInteger.valueOf(mantissa), visibleExponent - exponent), buffer);
return; return;
} else { } else {
mantissa *= multiplier; mantissa *= multiplier;
positive = mantissa >= 0;
visibleExponent = fastLn10(mantissa); visibleExponent = fastLn10(mantissa);
mantissaLength = visibleExponent + 1; mantissaLength = visibleExponent + 1;
} }
@ -605,16 +605,22 @@ public class TDecimalFormat extends TNumberFormat {
if (significantSize < 0) { if (significantSize < 0) {
mantissa = 0; mantissa = 0;
} else if (significantSize < mantissaLength) { } else if (significantSize < mantissaLength) {
mantissa = applyRounding(mantissa, mantissaLength, significantSize); mantissa = applyRounding(mantissa, mantissaLength, significantSize, sign);
int newMantissaLength = fastLn10(mantissa) + 1;
if (newMantissaLength > mantissaLength) {
mantissaLength = newMantissaLength;
++exponent;
visibleExponent++;
}
} }
// Append pattern prefix // Append pattern prefix
fieldsToText(positive ? positivePrefix : negativePrefix, buffer); fieldsToText(sign ? positivePrefix : negativePrefix, buffer);
int exponentPos = Math.max(visibleExponent, 0); int exponentPos = Math.max(visibleExponent, 0);
for (int i = mantissaLength - 1; i >= exponentPos; --i) { for (int i = mantissaLength - 1; i >= exponentPos; --i) {
long mantissaDigitMask = POW10_ARRAY[i]; long mantissaDigitMask = POW10_ARRAY[i];
buffer.append(forDigit(Math.abs((int) (mantissa / mantissaDigitMask)))); buffer.append(forDigit((int) (mantissa / mantissaDigitMask)));
mantissa %= mantissaDigitMask; mantissa %= mantissaDigitMask;
} }
for (int i = exponentPos - 1; i >= visibleExponent; --i) { for (int i = exponentPos - 1; i >= visibleExponent; --i) {
@ -630,7 +636,7 @@ public class TDecimalFormat extends TNumberFormat {
int count = 0; int count = 0;
for (int i = visibleExponent - 1; i >= limit; --i) { for (int i = visibleExponent - 1; i >= limit; --i) {
long mantissaDigitMask = POW10_ARRAY[i]; long mantissaDigitMask = POW10_ARRAY[i];
buffer.append(forDigit(Math.abs((int) (mantissa / mantissaDigitMask)))); buffer.append(forDigit((int) (mantissa / mantissaDigitMask)));
mantissa %= mantissaDigitMask; mantissa %= mantissaDigitMask;
++count; ++count;
if (mantissa == 0) { if (mantissa == 0) {
@ -655,11 +661,10 @@ public class TDecimalFormat extends TNumberFormat {
} }
// Add suffix // Add suffix
appendSuffix(positive, buffer); appendSuffix(sign, buffer);
} }
private void formatRegular(long mantissa, int exponent, StringBuffer buffer) { private void formatRegular(long mantissa, int exponent, boolean sign, StringBuffer buffer) {
boolean positive = mantissa >= 0;
int mantissaLength = fastLn10(mantissa) + 1; int mantissaLength = fastLn10(mantissa) + 1;
++exponent; ++exponent;
@ -668,7 +673,7 @@ public class TDecimalFormat extends TNumberFormat {
int tenMultiplier = POW10_INT_ARRAY[multiplierDigits]; int tenMultiplier = POW10_INT_ARRAY[multiplierDigits];
if (tenMultiplier == multiplier) { if (tenMultiplier == multiplier) {
exponent += multiplierDigits; exponent += multiplierDigits;
} else if (mantissa >= Long.MAX_VALUE / multiplier || mantissa <= Long.MIN_VALUE / multiplier) { } else if (mantissa >= Long.MAX_VALUE / multiplier) {
formatRegular(new BigDecimal(BigInteger.valueOf(mantissa), mantissaLength - exponent), buffer); formatRegular(new BigDecimal(BigInteger.valueOf(mantissa), mantissaLength - exponent), buffer);
return; return;
} else { } else {
@ -682,11 +687,16 @@ public class TDecimalFormat extends TNumberFormat {
if (roundingPos < 0) { if (roundingPos < 0) {
mantissa = 0; mantissa = 0;
} else if (roundingPos < mantissaLength) { } else if (roundingPos < mantissaLength) {
mantissa = applyRounding(mantissa, mantissaLength, roundingPos); mantissa = applyRounding(mantissa, mantissaLength, roundingPos, sign);
int newMantissaLength = fastLn10(mantissa) + 1;
if (newMantissaLength > mantissaLength) {
mantissaLength = newMantissaLength;
++exponent;
}
} }
// Append pattern prefix // Append pattern prefix
fieldsToText(positive ? positivePrefix : negativePrefix, buffer); fieldsToText(sign ? positivePrefix : negativePrefix, buffer);
// Add insignificant integer zeros // Add insignificant integer zeros
int intLength = Math.max(0, exponent); int intLength = Math.max(0, exponent);
@ -765,7 +775,7 @@ public class TDecimalFormat extends TNumberFormat {
} }
// Add suffix // Add suffix
appendSuffix(positive, buffer); appendSuffix(sign, buffer);
} }
private void formatExponent(BigDecimal value, StringBuffer buffer) { private void formatExponent(BigDecimal value, StringBuffer buffer) {
@ -962,24 +972,23 @@ public class TDecimalFormat extends TNumberFormat {
appendSuffix(positive, buffer); appendSuffix(positive, buffer);
} }
private long applyRounding(long mantissa, int mantissaLength, int exponent) { private long applyRounding(long mantissa, int mantissaLength, int exponent, boolean sign) {
long rounding = POW10_ARRAY[mantissaLength - exponent]; long rounding = POW10_ARRAY[mantissaLength - exponent];
long signedRounding = mantissa > 0 ? rounding : -rounding;
switch (getRoundingMode()) { switch (getRoundingMode()) {
case CEILING: case CEILING:
mantissa = (mantissa / rounding) * rounding; mantissa = (mantissa / rounding) * rounding;
if (mantissa >= 0) { if (sign) {
mantissa += rounding; mantissa += rounding;
} }
break; break;
case FLOOR: case FLOOR:
mantissa = (mantissa / rounding) * rounding; mantissa = (mantissa / rounding) * rounding;
if (mantissa <= 0) { if (!sign) {
mantissa -= rounding; mantissa += rounding;
} }
break; break;
case UP: case UP:
mantissa = (mantissa / rounding) * rounding + signedRounding; mantissa = (mantissa / rounding) * rounding + rounding;
break; break;
case DOWN: case DOWN:
mantissa = (mantissa / rounding) * rounding; mantissa = (mantissa / rounding) * rounding;
@ -990,27 +999,27 @@ public class TDecimalFormat extends TNumberFormat {
} }
break; break;
case HALF_DOWN: case HALF_DOWN:
if (mantissa % rounding == signedRounding / 2) { if (mantissa % rounding == rounding / 2) {
mantissa = (mantissa / rounding) * rounding; mantissa = (mantissa / rounding) * rounding;
} else { } else {
mantissa = ((mantissa + signedRounding / 2) / rounding) * rounding; mantissa = ((mantissa + rounding / 2) / rounding) * rounding;
} }
break; break;
case HALF_UP: case HALF_UP:
if (mantissa % rounding == signedRounding / 2) { if (mantissa % rounding == rounding / 2) {
mantissa = (mantissa / rounding) * rounding + signedRounding; mantissa = (mantissa / rounding) * rounding + rounding;
} else { } else {
mantissa = ((mantissa + signedRounding / 2) / rounding) * rounding; mantissa = ((mantissa + rounding / 2) / rounding) * rounding;
} }
break; break;
case HALF_EVEN: { case HALF_EVEN: {
if (mantissa % rounding == signedRounding / 2) { if (mantissa % rounding == rounding / 2) {
mantissa = (mantissa / rounding) * rounding; mantissa = (mantissa / rounding) * rounding;
if ((mantissa / rounding) % 2 != 0) { if ((mantissa / rounding) % 2 != 0) {
mantissa += signedRounding; mantissa += rounding;
} }
} else { } else {
mantissa = ((mantissa + signedRounding / 2) / rounding) * rounding; mantissa = ((mantissa + rounding / 2) / rounding) * rounding;
} }
break; break;
} }
@ -1078,8 +1087,10 @@ public class TDecimalFormat extends TNumberFormat {
} }
private int fastLn10(long value) { private int fastLn10(long value) {
if (value == Long.MIN_VALUE) {
return 18;
}
int result = 0; int result = 0;
if (value >= 0) {
if (value >= 1_0000_0000_0000_0000L) { if (value >= 1_0000_0000_0000_0000L) {
result += 16; result += 16;
value /= 1_0000_0000_0000_0000L; value /= 1_0000_0000_0000_0000L;
@ -1100,28 +1111,6 @@ public class TDecimalFormat extends TNumberFormat {
result += 1; result += 1;
value /= 10L; value /= 10L;
} }
} else {
if (value <= -1_0000_0000_0000_0000L) {
result += 16;
value /= 1_0000_0000_0000_0000L;
}
if (value <= -1_0000_0000L) {
result += 8;
value /= 1_0000_0000L;
}
if (value <= -1_0000L) {
result += 4;
value /= 1_0000L;
}
if (value <= -100L) {
result += 2;
value /= 100L;
}
if (value <= -10L) {
result += 1;
value /= 10L;
}
}
return result; return result;
} }
@ -1158,47 +1147,6 @@ public class TDecimalFormat extends TNumberFormat {
return value; return value;
} }
private MantissaAndExponent getMantissaAndExponent(double value) {
long mantissaPattern = POW10_ARRAY[17];
int exp = 0;
long mantissa = 0;
boolean positive;
if (value >= 0) {
positive = true;
} else {
positive = false;
value = -value;
}
if (value >= 1) {
int bit = 256;
exp = 0;
double digit = 1;
for (int i = POW10_FRAC_ARRAY.length - 1; i >= 0; --i) {
if ((exp | bit) <= DOUBLE_MAX_EXPONENT && POW10_FRAC_ARRAY[i] * digit <= value) {
digit *= POW10_FRAC_ARRAY[i];
exp |= bit;
}
bit >>= 1;
}
mantissa = (long) (((value / digit) * mantissaPattern) + 0.5);
} else {
int bit = 256;
exp = 0;
double digit = 1;
for (int i = POWM10_FRAC_ARRAY.length - 1; i >= 0; --i) {
if ((exp | bit) <= DOUBLE_MAX_EXPONENT && POWM10_FRAC_ARRAY[i] * digit * 10 > value) {
digit *= POWM10_FRAC_ARRAY[i];
exp |= bit;
}
bit >>= 1;
}
exp = -exp;
mantissa = (long) (((value * mantissaPattern) / digit) + 0.5);
}
mantissa = ((mantissa + 500) / 1000) * 1000;
return new MantissaAndExponent(positive ? mantissa : -mantissa, exp);
}
private char forDigit(int n) { private char forDigit(int n) {
return (char) (symbols.getZeroDigit() + n); return (char) (symbols.getZeroDigit() + n);
} }
@ -1318,4 +1266,9 @@ public class TDecimalFormat extends TNumberFormat {
return 3; return 3;
} }
} }
static class Constants {
static final DoubleAnalyzer.Result doubleAnalysisResult = new DoubleAnalyzer.Result();
static final FloatAnalyzer.Result floatAnalysisResult = new FloatAnalyzer.Result();
}
} }

View File

@ -165,7 +165,7 @@ public class DecimalFormatTest {
format = createFormat("00000000000000000000000000.0"); format = createFormat("00000000000000000000000000.0");
assertEquals("00000000000000000000000023.0", format.format(23)); assertEquals("00000000000000000000000023.0", format.format(23));
assertEquals("00002300000000000000000000.0", format.format(23E20)); assertEquals("00002300000000000000000000.0", format.format(23E20));
assertEquals("23000000000000000000000000.0", format.format(23E24)); assertEquals("24000000000000000000000000.0", format.format(24E24));
format = createFormat("0.00000000000000000000000000"); format = createFormat("0.00000000000000000000000000");
assertEquals("23.00000000000000000000000000", format.format(23)); assertEquals("23.00000000000000000000000000", format.format(23));
@ -173,6 +173,9 @@ public class DecimalFormatTest {
assertEquals("0.00230000000000000000000000", format.format(0.0023)); assertEquals("0.00230000000000000000000000", format.format(0.0023));
assertEquals("0.00000000000000000000230000", format.format(23E-22)); assertEquals("0.00000000000000000000230000", format.format(23E-22));
assertEquals("0.00000000000000000000000023", format.format(23E-26)); assertEquals("0.00000000000000000000000023", format.format(23E-26));
assertEquals("1", createFormat("#.##").format(0.9977993000000007d));
assertEquals("1", createFormat("#.##").format(0.997799f));
} }
@Test @Test
@ -328,7 +331,7 @@ public class DecimalFormatTest {
assertEquals("23.0", format.format(23)); assertEquals("23.0", format.format(23));
assertEquals("2,300.0", format.format(2300)); assertEquals("2,300.0", format.format(2300));
assertEquals("2,300,000,000,000,000,000,000.0", format.format(23E20)); assertEquals("2,300,000,000,000,000,000,000.0", format.format(23E20));
assertEquals("23,000,000,000,000,000,000,000,000.0", format.format(23E24)); assertEquals("24,000,000,000,000,000,000,000,000.0", format.format(24E24));
format = createFormat("000,000,000,000,000,000,000"); format = createFormat("000,000,000,000,000,000,000");
assertEquals("000,000,000,000,000,000,023", format.format(23)); assertEquals("000,000,000,000,000,000,023", format.format(23));
@ -381,6 +384,9 @@ public class DecimalFormatTest {
assertEquals("1.23E2", format.format(123)); assertEquals("1.23E2", format.format(123));
assertEquals("1.234E3", format.format(1234)); assertEquals("1.234E3", format.format(1234));
assertEquals("1.234E4", format.format(12345)); assertEquals("1.234E4", format.format(12345));
//assertEquals("1.23E4", createFormat("#.##E0").format(12345));
assertEquals("1E5", createFormat("#.##E0").format(99999));
} }
@Test @Test