diff --git a/src/main/java/org/apache/commons/lang3/math/Fraction.java b/src/main/java/org/apache/commons/lang3/math/Fraction.java index 5ef12b461..100bd1680 100644 --- a/src/main/java/org/apache/commons/lang3/math/Fraction.java +++ b/src/main/java/org/apache/commons/lang3/math/Fraction.java @@ -143,8 +143,7 @@ public final class Fraction extends Number implements Comparable { throw new ArithmeticException("The denominator must not be zero"); } if (denominator < 0) { - if (numerator==Integer.MIN_VALUE || - denominator==Integer.MIN_VALUE) { + if (numerator == Integer.MIN_VALUE || denominator == Integer.MIN_VALUE) { throw new ArithmeticException("overflow: can't negate"); } numerator = -numerator; @@ -181,12 +180,11 @@ public final class Fraction extends Number implements Comparable { } long numeratorValue; if (whole < 0) { - numeratorValue = whole * (long)denominator - numerator; + numeratorValue = whole * (long) denominator - numerator; } else { - numeratorValue = whole * (long)denominator + numerator; + numeratorValue = whole * (long) denominator + numerator; } - if (numeratorValue < Integer.MIN_VALUE || - numeratorValue > Integer.MAX_VALUE) { + if (numeratorValue < Integer.MIN_VALUE || numeratorValue > Integer.MAX_VALUE) { throw new ArithmeticException("Numerator too large to represent as an Integer."); } return new Fraction((int) numeratorValue, denominator); @@ -210,16 +208,16 @@ public final class Fraction extends Number implements Comparable { if (denominator == 0) { throw new ArithmeticException("The denominator must not be zero"); } - if (numerator==0) { + if (numerator == 0) { return ZERO; // normalize zero. } // allow 2^k/-2^31 as a valid fraction (where k>0) - if (denominator==Integer.MIN_VALUE && (numerator&1)==0) { - numerator/=2; denominator/=2; + if (denominator == Integer.MIN_VALUE && (numerator & 1) == 0) { + numerator /= 2; + denominator /= 2; } if (denominator < 0) { - if (numerator==Integer.MIN_VALUE || - denominator==Integer.MIN_VALUE) { + if (numerator == Integer.MIN_VALUE || denominator == Integer.MIN_VALUE) { throw new ArithmeticException("overflow: can't negate"); } numerator = -numerator; @@ -249,19 +247,18 @@ public final class Fraction extends Number implements Comparable { public static Fraction getFraction(double value) { final int sign = value < 0 ? -1 : 1; value = Math.abs(value); - if (value > Integer.MAX_VALUE || Double.isNaN(value)) { - throw new ArithmeticException - ("The value must not be greater than Integer.MAX_VALUE or NaN"); + if (value > Integer.MAX_VALUE || Double.isNaN(value)) { + throw new ArithmeticException("The value must not be greater than Integer.MAX_VALUE or NaN"); } final int wholeNumber = (int) value; value -= wholeNumber; - - int numer0 = 0; // the pre-previous - int denom0 = 1; // the pre-previous - int numer1 = 1; // the previous - int denom1 = 0; // the previous - int numer2 = 0; // the current, setup in calculation - int denom2 = 0; // the current, setup in calculation + + int numer0 = 0; // the pre-previous + int denom0 = 1; // the pre-previous + int numer1 = 1; // the previous + int denom1 = 0; // the previous + int numer2 = 0; // the current, setup in calculation + int denom2 = 0; // the current, setup in calculation int a1 = (int) value; int a2 = 0; double x1 = 1; @@ -271,7 +268,7 @@ public final class Fraction extends Number implements Comparable { double delta1, delta2 = Double.MAX_VALUE; double fraction; int i = 1; -// System.out.println("---"); + // System.out.println("---"); do { delta1 = delta2; a2 = (int) (x1 / y1); @@ -281,7 +278,7 @@ public final class Fraction extends Number implements Comparable { denom2 = a1 * denom1 + denom0; fraction = (double) numer2 / (double) denom2; delta2 = Math.abs(value - fraction); -// System.out.println(numer2 + " " + denom2 + " " + fraction + " " + delta2 + " " + y1); + // System.out.println(numer2 + " " + denom2 + " " + fraction + " " + delta2 + " " + y1); a1 = a2; x1 = x2; y1 = y2; @@ -290,7 +287,7 @@ public final class Fraction extends Number implements Comparable { numer1 = numer2; denom1 = denom2; i++; -// System.out.println(">>" + delta1 +" "+ delta2+" "+(delta1 > delta2)+" "+i+" "+denom2); + // System.out.println(">>" + delta1 +" "+ delta2+" "+(delta1 > delta2)+" "+i+" "+denom2); } while (delta1 > delta2 && denom2 <= 10000 && denom2 > 0 && i < 25); if (i == 25) { throw new ArithmeticException("Unable to convert double to fraction"); @@ -546,16 +543,16 @@ public final class Fraction extends Number implements Comparable { } else if (power == 0) { return ONE; } else if (power < 0) { - if (power==Integer.MIN_VALUE) { // MIN_VALUE can't be negated. - return this.invert().pow(2).pow(-(power/2)); + if (power == Integer.MIN_VALUE) { // MIN_VALUE can't be negated. + return this.invert().pow(2).pow(-(power / 2)); } return this.invert().pow(-power); } else { final Fraction f = this.multiplyBy(this); if (power % 2 == 0) { // if even... - return f.pow(power/2); + return f.pow(power / 2); } - return f.pow(power/2).multiplyBy(this); + return f.pow(power / 2).multiplyBy(this); } } @@ -577,7 +574,7 @@ public final class Fraction extends Number implements Comparable { } return Math.abs(u) + Math.abs(v); } - //if either operand is abs 1, return 1: + // if either operand is abs 1, return 1: if (Math.abs(u) == 1 || Math.abs(v) == 1) { return 1; } @@ -585,39 +582,45 @@ public final class Fraction extends Number implements Comparable { // -2^31, while positive numbers can only be as large as 2^31-1 // (i.e. we can't necessarily negate a negative number without // overflow) - if (u>0) { u=-u; } // make u negative - if (v>0) { v=-v; } // make v negative + if (u > 0) { + u = -u; + } // make u negative + if (v > 0) { + v = -v; + } // make v negative // B1. [Find power of 2] - int k=0; - while ((u&1)==0 && (v&1)==0 && k<31) { // while u and v are both even... - u/=2; v/=2; k++; // cast out twos. + int k = 0; + while ((u & 1) == 0 && (v & 1) == 0 && k < 31) { // while u and v are both even... + u /= 2; + v /= 2; + k++; // cast out twos. } - if (k==31) { + if (k == 31) { throw new ArithmeticException("overflow: gcd is 2^31"); } // B2. Initialize: u and v have been divided by 2^k and at least - // one is odd. - int t = (u&1)==1 ? v : -(u/2)/*B3*/; + // one is odd. + int t = (u & 1) == 1 ? v : -(u / 2)/* B3 */; // t negative: u was odd, v may be even (t replaces v) // t positive: u was even, v is odd (t replaces u) do { /* assert u<0 && v<0; */ // B4/B3: cast out twos from t. - while ((t&1)==0) { // while t is even.. - t/=2; // cast out twos + while ((t & 1) == 0) { // while t is even.. + t /= 2; // cast out twos } // B5 [reset max(u,v)] - if (t>0) { + if (t > 0) { u = -t; } else { v = t; } // B6/B3. at this point both u and v should be odd. - t = (v - u)/2; + t = (v - u) / 2; // |u| larger: t positive (replace u) // |v| larger: t negative (replace v) - } while (t!=0); - return -u*(1< { * an int */ private static int mulAndCheck(final int x, final int y) { - final long m = (long)x*(long)y; - if (m < Integer.MIN_VALUE || - m > Integer.MAX_VALUE) { + final long m = (long) x * (long) y; + if (m < Integer.MIN_VALUE || m > Integer.MAX_VALUE) { throw new ArithmeticException("overflow: mul"); } - return (int)m; + return (int) m; } /** @@ -652,11 +654,11 @@ public final class Fraction extends Number implements Comparable { */ private static int mulPosAndCheck(final int x, final int y) { /* assert x>=0 && y>=0; */ - final long m = (long)x*(long)y; + final long m = (long) x * (long) y; if (m > Integer.MAX_VALUE) { throw new ArithmeticException("overflow: mulPos"); } - return (int)m; + return (int) m; } /** @@ -669,12 +671,11 @@ public final class Fraction extends Number implements Comparable { * an int */ private static int addAndCheck(final int x, final int y) { - final long s = (long)x+(long)y; - if (s < Integer.MIN_VALUE || - s > Integer.MAX_VALUE) { + final long s = (long) x + (long) y; + if (s < Integer.MIN_VALUE || s > Integer.MAX_VALUE) { throw new ArithmeticException("overflow: add"); } - return (int)s; + return (int) s; } /** @@ -687,12 +688,11 @@ public final class Fraction extends Number implements Comparable { * an int */ private static int subAndCheck(final int x, final int y) { - final long s = (long)x-(long)y; - if (s < Integer.MIN_VALUE || - s > Integer.MAX_VALUE) { + final long s = (long) x - (long) y; + if (s < Integer.MIN_VALUE || s > Integer.MAX_VALUE) { throw new ArithmeticException("overflow: add"); } - return (int)s; + return (int) s; } /** @@ -743,40 +743,34 @@ public final class Fraction extends Number implements Comparable { } if (fraction.numerator == 0) { return this; - } + } // if denominators are randomly distributed, d1 will be 1 about 61% // of the time. final int d1 = greatestCommonDivisor(denominator, fraction.denominator); - if (d1==1) { + if (d1 == 1) { // result is ( (u*v' +/- u'v) / u'v') final int uvp = mulAndCheck(numerator, fraction.denominator); final int upv = mulAndCheck(fraction.numerator, denominator); - return new Fraction - (isAdd ? addAndCheck(uvp, upv) : subAndCheck(uvp, upv), - mulPosAndCheck(denominator, fraction.denominator)); + return new Fraction(isAdd ? addAndCheck(uvp, upv) : subAndCheck(uvp, upv), mulPosAndCheck(denominator, + fraction.denominator)); } // the quantity 't' requires 65 bits of precision; see knuth 4.5.1 - // exercise 7. we're going to use a BigInteger. + // exercise 7. we're going to use a BigInteger. // t = u(v'/d1) +/- v(u'/d1) - final BigInteger uvp = BigInteger.valueOf(numerator) - .multiply(BigInteger.valueOf(fraction.denominator/d1)); - final BigInteger upv = BigInteger.valueOf(fraction.numerator) - .multiply(BigInteger.valueOf(denominator/d1)); + final BigInteger uvp = BigInteger.valueOf(numerator).multiply(BigInteger.valueOf(fraction.denominator / d1)); + final BigInteger upv = BigInteger.valueOf(fraction.numerator).multiply(BigInteger.valueOf(denominator / d1)); final BigInteger t = isAdd ? uvp.add(upv) : uvp.subtract(upv); // but d2 doesn't need extra precision because // d2 = gcd(t,d1) = gcd(t mod d1, d1) final int tmodd1 = t.mod(BigInteger.valueOf(d1)).intValue(); - final int d2 = tmodd1==0?d1:greatestCommonDivisor(tmodd1, d1); + final int d2 = tmodd1 == 0 ? d1 : greatestCommonDivisor(tmodd1, d1); // result is (t/d2) / (u'/d1)(v'/d2) final BigInteger w = t.divide(BigInteger.valueOf(d2)); if (w.bitLength() > 31) { - throw new ArithmeticException - ("overflow: numerator too large after multiply"); + throw new ArithmeticException("overflow: numerator too large after multiply"); } - return new Fraction - (w.intValue(), - mulPosAndCheck(denominator/d1, fraction.denominator/d2)); + return new Fraction(w.intValue(), mulPosAndCheck(denominator / d1, fraction.denominator / d2)); } /** @@ -800,9 +794,8 @@ public final class Fraction extends Number implements Comparable { // make sure we don't overflow unless the result *must* overflow. final int d1 = greatestCommonDivisor(numerator, fraction.denominator); final int d2 = greatestCommonDivisor(fraction.numerator, denominator); - return getReducedFraction - (mulAndCheck(numerator/d1, fraction.numerator/d2), - mulPosAndCheck(denominator/d2, fraction.denominator/d1)); + return getReducedFraction(mulAndCheck(numerator / d1, fraction.numerator / d2), + mulPosAndCheck(denominator / d2, fraction.denominator / d1)); } /** @@ -845,8 +838,7 @@ public final class Fraction extends Number implements Comparable { return false; } final Fraction other = (Fraction) obj; - return getNumerator() == other.getNumerator() && - getDenominator() == other.getDenominator(); + return getNumerator() == other.getNumerator() && getDenominator() == other.getDenominator(); } /** @@ -877,7 +869,7 @@ public final class Fraction extends Number implements Comparable { */ @Override public int compareTo(final Fraction other) { - if (this==other) { + if (this == other) { return 0; } if (numerator == other.numerator && denominator == other.denominator) { @@ -906,10 +898,7 @@ public final class Fraction extends Number implements Comparable { @Override public String toString() { if (toString == null) { - toString = new StringBuilder(32) - .append(getNumerator()) - .append('/') - .append(getDenominator()).toString(); + toString = new StringBuilder(32).append(getNumerator()).append('/').append(getDenominator()).toString(); } return toString; } @@ -931,24 +920,21 @@ public final class Fraction extends Number implements Comparable { toProperString = "1"; } else if (numerator == -1 * denominator) { toProperString = "-1"; - } else if ((numerator>0?-numerator:numerator) < -denominator) { + } else if ((numerator > 0 ? -numerator : numerator) < -denominator) { // note that we do the magnitude comparison test above with // NEGATIVE (not positive) numbers, since negative numbers - // have a larger range. otherwise numerator==Integer.MIN_VALUE + // have a larger range. otherwise numerator==Integer.MIN_VALUE // is handled incorrectly. final int properNumerator = getProperNumerator(); if (properNumerator == 0) { toProperString = Integer.toString(getProperWhole()); } else { - toProperString = new StringBuilder(32) - .append(getProperWhole()).append(' ') - .append(properNumerator).append('/') - .append(getDenominator()).toString(); + toProperString = new StringBuilder(32).append(getProperWhole()).append(' ').append(properNumerator) + .append('/').append(getDenominator()).toString(); } } else { - toProperString = new StringBuilder(32) - .append(getNumerator()).append('/') - .append(getDenominator()).toString(); + toProperString = new StringBuilder(32).append(getNumerator()).append('/').append(getDenominator()) + .toString(); } } return toProperString;