OpenJDK / jdk / hs
changeset 23934:e99a4768951e
6375303: Review use of caching in BigDecimal
Summary: Clean up of various items discovered during review of caching.
Reviewed-by: mduigou, psandoz
| author | bpb |
|---|---|
| date | Wed, 16 Apr 2014 12:59:41 -0700 |
| parents | 0c547f072113 |
| children | 4daeffbde72f |
| files | jdk/src/share/classes/java/math/BigDecimal.java |
| diffstat | 1 files changed, 90 insertions(+), 82 deletions(-) [+] |
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--- a/jdk/src/share/classes/java/math/BigDecimal.java Wed Apr 16 11:56:58 2014 +0100 +++ b/jdk/src/share/classes/java/math/BigDecimal.java Wed Apr 16 12:59:41 2014 -0700 @@ -29,8 +29,8 @@ package java.math; +import static java.math.BigInteger.LONG_MASK; import java.util.Arrays; -import static java.math.BigInteger.LONG_MASK; /** * Immutable, arbitrary-precision signed decimal numbers. A @@ -283,7 +283,7 @@ }; // Cache of common small BigDecimal values. - private static final BigDecimal zeroThroughTen[] = { + private static final BigDecimal ZERO_THROUGH_TEN[] = { new BigDecimal(BigInteger.ZERO, 0, 0, 1), new BigDecimal(BigInteger.ONE, 1, 0, 1), new BigDecimal(BigInteger.valueOf(2), 2, 0, 1), @@ -299,7 +299,7 @@ // Cache of zero scaled by 0 - 15 private static final BigDecimal[] ZERO_SCALED_BY = { - zeroThroughTen[0], + ZERO_THROUGH_TEN[0], new BigDecimal(BigInteger.ZERO, 0, 1, 1), new BigDecimal(BigInteger.ZERO, 0, 2, 1), new BigDecimal(BigInteger.ZERO, 0, 3, 1), @@ -328,7 +328,7 @@ * @since 1.5 */ public static final BigDecimal ZERO = - zeroThroughTen[0]; + ZERO_THROUGH_TEN[0]; /** * The value 1, with a scale of 0. @@ -336,7 +336,7 @@ * @since 1.5 */ public static final BigDecimal ONE = - zeroThroughTen[1]; + ZERO_THROUGH_TEN[1]; /** * The value 10, with a scale of 0. @@ -344,7 +344,7 @@ * @since 1.5 */ public static final BigDecimal TEN = - zeroThroughTen[10]; + ZERO_THROUGH_TEN[10]; // Constructors @@ -920,20 +920,20 @@ significand >>= 1; exponent++; } - int scale = 0; + int scl = 0; // Calculate intVal and scale - BigInteger intVal; + BigInteger rb; long compactVal = sign * significand; if (exponent == 0) { - intVal = (compactVal == INFLATED) ? INFLATED_BIGINT : null; + rb = (compactVal == INFLATED) ? INFLATED_BIGINT : null; } else { if (exponent < 0) { - intVal = BigInteger.valueOf(5).pow(-exponent).multiply(compactVal); - scale = -exponent; + rb = BigInteger.valueOf(5).pow(-exponent).multiply(compactVal); + scl = -exponent; } else { // (exponent > 0) - intVal = BigInteger.valueOf(2).pow(exponent).multiply(compactVal); + rb = BigInteger.valueOf(2).pow(exponent).multiply(compactVal); } - compactVal = compactValFor(intVal); + compactVal = compactValFor(rb); } int prec = 0; int mcp = mc.precision; @@ -941,16 +941,16 @@ int mode = mc.roundingMode.oldMode; int drop; if (compactVal == INFLATED) { - prec = bigDigitLength(intVal); + prec = bigDigitLength(rb); drop = prec - mcp; while (drop > 0) { - scale = checkScaleNonZero((long) scale - drop); - intVal = divideAndRoundByTenPow(intVal, drop, mode); - compactVal = compactValFor(intVal); + scl = checkScaleNonZero((long) scl - drop); + rb = divideAndRoundByTenPow(rb, drop, mode); + compactVal = compactValFor(rb); if (compactVal != INFLATED) { break; } - prec = bigDigitLength(intVal); + prec = bigDigitLength(rb); drop = prec - mcp; } } @@ -958,17 +958,17 @@ prec = longDigitLength(compactVal); drop = prec - mcp; while (drop > 0) { - scale = checkScaleNonZero((long) scale - drop); + scl = checkScaleNonZero((long) scl - drop); compactVal = divideAndRound(compactVal, LONG_TEN_POWERS_TABLE[drop], mc.roundingMode.oldMode); prec = longDigitLength(compactVal); drop = prec - mcp; } - intVal = null; + rb = null; } } - this.intVal = intVal; + this.intVal = rb; this.intCompact = compactVal; - this.scale = scale; + this.scale = scl; this.precision = prec; } @@ -1098,13 +1098,13 @@ public BigDecimal(int val, MathContext mc) { int mcp = mc.precision; long compactVal = val; - int scale = 0; + int scl = 0; int prec = 0; if (mcp > 0) { // do rounding prec = longDigitLength(compactVal); int drop = prec - mcp; // drop can't be more than 18 while (drop > 0) { - scale = checkScaleNonZero((long) scale - drop); + scl = checkScaleNonZero((long) scl - drop); compactVal = divideAndRound(compactVal, LONG_TEN_POWERS_TABLE[drop], mc.roundingMode.oldMode); prec = longDigitLength(compactVal); drop = prec - mcp; @@ -1112,7 +1112,7 @@ } this.intVal = null; this.intCompact = compactVal; - this.scale = scale; + this.scale = scl; this.precision = prec; } @@ -1144,20 +1144,20 @@ int mcp = mc.precision; int mode = mc.roundingMode.oldMode; int prec = 0; - int scale = 0; - BigInteger intVal = (val == INFLATED) ? INFLATED_BIGINT : null; + int scl = 0; + BigInteger rb = (val == INFLATED) ? INFLATED_BIGINT : null; if (mcp > 0) { // do rounding if (val == INFLATED) { prec = 19; int drop = prec - mcp; while (drop > 0) { - scale = checkScaleNonZero((long) scale - drop); - intVal = divideAndRoundByTenPow(intVal, drop, mode); - val = compactValFor(intVal); + scl = checkScaleNonZero((long) scl - drop); + rb = divideAndRoundByTenPow(rb, drop, mode); + val = compactValFor(rb); if (val != INFLATED) { break; } - prec = bigDigitLength(intVal); + prec = bigDigitLength(rb); drop = prec - mcp; } } @@ -1165,17 +1165,17 @@ prec = longDigitLength(val); int drop = prec - mcp; while (drop > 0) { - scale = checkScaleNonZero((long) scale - drop); + scl = checkScaleNonZero((long) scl - drop); val = divideAndRound(val, LONG_TEN_POWERS_TABLE[drop], mc.roundingMode.oldMode); prec = longDigitLength(val); drop = prec - mcp; } - intVal = null; + rb = null; } } - this.intVal = intVal; + this.intVal = rb; this.intCompact = val; - this.scale = scale; + this.scale = scl; this.precision = prec; } @@ -1215,16 +1215,16 @@ * @return a {@code BigDecimal} whose value is {@code val}. */ public static BigDecimal valueOf(long val) { - if (val >= 0 && val < zeroThroughTen.length) - return zeroThroughTen[(int)val]; + if (val >= 0 && val < ZERO_THROUGH_TEN.length) + return ZERO_THROUGH_TEN[(int)val]; else if (val != INFLATED) return new BigDecimal(null, val, 0, 0); return new BigDecimal(INFLATED_BIGINT, val, 0, 0); } static BigDecimal valueOf(long unscaledVal, int scale, int prec) { - if (scale == 0 && unscaledVal >= 0 && unscaledVal < zeroThroughTen.length) { - return zeroThroughTen[(int) unscaledVal]; + if (scale == 0 && unscaledVal >= 0 && unscaledVal < ZERO_THROUGH_TEN.length) { + return ZERO_THROUGH_TEN[(int) unscaledVal]; } else if (unscaledVal == 0) { return zeroValueOf(scale); } @@ -1236,8 +1236,8 @@ long val = compactValFor(intVal); if (val == 0) { return zeroValueOf(scale); - } else if (scale == 0 && val >= 0 && val < zeroThroughTen.length) { - return zeroThroughTen[(int) val]; + } else if (scale == 0 && val >= 0 && val < ZERO_THROUGH_TEN.length) { + return ZERO_THROUGH_TEN[(int) val]; } return new BigDecimal(intVal, val, scale, prec); } @@ -2620,6 +2620,7 @@ * @return -1, 0, or 1 as this {@code BigDecimal} is numerically * less than, equal to, or greater than {@code val}. */ + @Override public int compareTo(BigDecimal val) { // Quick path for equal scale and non-inflated case. if (scale == val.scale) { @@ -2659,14 +2660,13 @@ return -1; if (xae > yae) return 1; - BigInteger rb = null; if (sdiff < 0) { // The cases sdiff <= Integer.MIN_VALUE intentionally fall through. if ( sdiff > Integer.MIN_VALUE && (xs == INFLATED || (xs = longMultiplyPowerTen(xs, (int)-sdiff)) == INFLATED) && ys == INFLATED) { - rb = bigMultiplyPowerTen((int)-sdiff); + BigInteger rb = bigMultiplyPowerTen((int)-sdiff); return rb.compareMagnitude(val.intVal); } } else { // sdiff > 0 @@ -2675,7 +2675,7 @@ (ys == INFLATED || (ys = longMultiplyPowerTen(ys, (int)sdiff)) == INFLATED) && xs == INFLATED) { - rb = val.bigMultiplyPowerTen((int)sdiff); + BigInteger rb = val.bigMultiplyPowerTen((int)sdiff); return this.intVal.compareMagnitude(rb); } } @@ -2880,8 +2880,9 @@ @Override public String toString() { String sc = stringCache; - if (sc == null) + if (sc == null) { stringCache = sc = layoutChars(true); + } return sc; } @@ -2958,18 +2959,19 @@ if(signum()==0) { return "0"; } - int tailingZeros = checkScaleNonZero((-(long)scale)); + int trailingZeros = checkScaleNonZero((-(long)scale)); StringBuilder buf; if(intCompact!=INFLATED) { - buf = new StringBuilder(20+tailingZeros); + buf = new StringBuilder(20+trailingZeros); buf.append(intCompact); } else { String str = intVal.toString(); - buf = new StringBuilder(str.length()+tailingZeros); + buf = new StringBuilder(str.length()+trailingZeros); buf.append(str); } - for (int i = 0; i < tailingZeros; i++) + for (int i = 0; i < trailingZeros; i++) { buf.append('0'); + } return buf.toString(); } String str ; @@ -2996,8 +2998,9 @@ } else { /* We must insert zeros between point and intVal */ buf = new StringBuilder(3-insertionPoint + intString.length()); buf.append(signum<0 ? "-0." : "0."); - for (int i=0; i<-insertionPoint; i++) + for (int i=0; i<-insertionPoint; i++) { buf.append('0'); + } buf.append(intString); } return buf.toString(); @@ -3056,6 +3059,7 @@ * * @return this {@code BigDecimal} converted to a {@code long}. */ + @Override public long longValue(){ return (intCompact != INFLATED && scale == 0) ? intCompact: @@ -3124,6 +3128,7 @@ * * @return this {@code BigDecimal} converted to an {@code int}. */ + @Override public int intValue() { return (intCompact != INFLATED && scale == 0) ? (int)intCompact : @@ -3206,6 +3211,7 @@ * * @return this {@code BigDecimal} converted to a {@code float}. */ + @Override public float floatValue(){ if(intCompact != INFLATED) { if (scale == 0) { @@ -3221,10 +3227,10 @@ // Don't have too guard against // Math.abs(MIN_VALUE) because of outer check // against INFLATED. - if (scale > 0 && scale < float10pow.length) { - return (float)intCompact / float10pow[scale]; - } else if (scale < 0 && scale > -float10pow.length) { - return (float)intCompact * float10pow[-scale]; + if (scale > 0 && scale < FLOAT_10_POW.length) { + return (float)intCompact / FLOAT_10_POW[scale]; + } else if (scale < 0 && scale > -FLOAT_10_POW.length) { + return (float)intCompact * FLOAT_10_POW[-scale]; } } } @@ -3249,6 +3255,7 @@ * * @return this {@code BigDecimal} converted to a {@code double}. */ + @Override public double doubleValue(){ if(intCompact != INFLATED) { if (scale == 0) { @@ -3264,10 +3271,10 @@ // Don't have too guard against // Math.abs(MIN_VALUE) because of outer check // against INFLATED. - if (scale > 0 && scale < double10pow.length) { - return (double)intCompact / double10pow[scale]; - } else if (scale < 0 && scale > -double10pow.length) { - return (double)intCompact * double10pow[-scale]; + if (scale > 0 && scale < DOUBLE_10_POW.length) { + return (double)intCompact / DOUBLE_10_POW[scale]; + } else if (scale < 0 && scale > -DOUBLE_10_POW.length) { + return (double)intCompact * DOUBLE_10_POW[-scale]; } } } @@ -3280,7 +3287,7 @@ * Powers of 10 which can be represented exactly in {@code * double}. */ - private static final double double10pow[] = { + private static final double DOUBLE_10_POW[] = { 1.0e0, 1.0e1, 1.0e2, 1.0e3, 1.0e4, 1.0e5, 1.0e6, 1.0e7, 1.0e8, 1.0e9, 1.0e10, 1.0e11, 1.0e12, 1.0e13, 1.0e14, 1.0e15, 1.0e16, 1.0e17, @@ -3291,7 +3298,7 @@ * Powers of 10 which can be represented exactly in {@code * float}. */ - private static final float float10pow[] = { + private static final float FLOAT_10_POW[] = { 1.0e0f, 1.0e1f, 1.0e2f, 1.0e3f, 1.0e4f, 1.0e5f, 1.0e6f, 1.0e7f, 1.0e8f, 1.0e9f, 1.0e10f }; @@ -3504,8 +3511,9 @@ } else if (sig >= coeffLen) { // significand all in integer buf.append(coeff, offset, coeffLen); // may need some zeros, too - for (int i = sig - coeffLen; i > 0; i--) + for (int i = sig - coeffLen; i > 0; i--) { buf.append('0'); + } } else { // xx.xxE form buf.append(coeff, offset, sig); buf.append('.'); @@ -3559,11 +3567,13 @@ // to prevent multiple threads from expanding the same array. if (curLen <= n) { int newLen = curLen << 1; - while (newLen <= n) + while (newLen <= n) { newLen <<= 1; + } pows = Arrays.copyOf(pows, newLen); - for (int i = curLen; i < newLen; i++) + for (int i = curLen; i < newLen; i++) { pows[i] = pows[i - 1].multiply(BigInteger.TEN); + } // Based on the following facts: // 1. pows is a private local varible; // 2. the following store is a volatile store. @@ -3703,9 +3713,7 @@ * {@code BigDecimal}s to be aligned. */ private static void matchScale(BigDecimal[] val) { - if (val[0].scale == val[1].scale) { - return; - } else if (val[0].scale < val[1].scale) { + if (val[0].scale < val[1].scale) { val[0] = val[0].setScale(val[1].scale, ROUND_UNNECESSARY); } else if (val[1].scale < val[0].scale) { val[1] = val[1].setScale(val[0].scale, ROUND_UNNECESSARY); @@ -4209,16 +4217,16 @@ * do rounding based on the passed in roundingMode. */ private static BigInteger divideAndRound(BigInteger bdividend, long ldivisor, int roundingMode) { - boolean isRemainderZero; // record remainder is zero or not - int qsign; // quotient sign - long r = 0; // store quotient & remainder in long - MutableBigInteger mq = null; // store quotient // Descend into mutables for faster remainder checks MutableBigInteger mdividend = new MutableBigInteger(bdividend.mag); - mq = new MutableBigInteger(); - r = mdividend.divide(ldivisor, mq); - isRemainderZero = (r == 0); - qsign = (ldivisor < 0) ? -bdividend.signum : bdividend.signum; + // store quotient + MutableBigInteger mq = new MutableBigInteger(); + // store quotient & remainder in long + long r = mdividend.divide(ldivisor, mq); + // record remainder is zero or not + boolean isRemainderZero = (r == 0); + // quotient sign + int qsign = (ldivisor < 0) ? -bdividend.signum : bdividend.signum; if (!isRemainderZero) { if(needIncrement(ldivisor, roundingMode, qsign, mq, r)) { mq.add(MutableBigInteger.ONE); @@ -4238,16 +4246,16 @@ */ private static BigDecimal divideAndRound(BigInteger bdividend, long ldivisor, int scale, int roundingMode, int preferredScale) { - boolean isRemainderZero; // record remainder is zero or not - int qsign; // quotient sign - long r = 0; // store quotient & remainder in long - MutableBigInteger mq = null; // store quotient // Descend into mutables for faster remainder checks MutableBigInteger mdividend = new MutableBigInteger(bdividend.mag); - mq = new MutableBigInteger(); - r = mdividend.divide(ldivisor, mq); - isRemainderZero = (r == 0); - qsign = (ldivisor < 0) ? -bdividend.signum : bdividend.signum; + // store quotient + MutableBigInteger mq = new MutableBigInteger(); + // store quotient & remainder in long + long r = mdividend.divide(ldivisor, mq); + // record remainder is zero or not + boolean isRemainderZero = (r == 0); + // quotient sign + int qsign = (ldivisor < 0) ? -bdividend.signum : bdividend.signum; if (!isRemainderZero) { if(needIncrement(ldivisor, roundingMode, qsign, mq, r)) { mq.add(MutableBigInteger.ONE);