- /* ====================================================================
- * The Apache Software License, Version 1.1
- *
- * Copyright (c) 2002-2003 The Apache Software Foundation. All rights
- * reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. The end-user documentation included with the redistribution, if
- * any, must include the following acknowledgement:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowledgement may appear in the software itself,
- * if and wherever such third-party acknowledgements normally appear.
- *
- * 4. The names "The Jakarta Project", "Commons", and "Apache Software
- * Foundation" must not be used to endorse or promote products derived
- * from this software without prior written permission. For written
- * permission, please contact apache@apache.org.
- *
- * 5. Products derived from this software may not be called "Apache"
- * nor may "Apache" appear in their names without prior written
- * permission of the Apache Software Foundation.
- *
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
- * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * ====================================================================
- *
- * This software consists of voluntary contributions made by many
- * individuals on behalf of the Apache Software Foundation. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- */
- package org.apache.commons.lang.math;
-
- import java.io.Serializable;
-
- /**
- * <p><code>Fraction</code> is a <code>Number</code> implementation that
- * stores fractions accurately.</p>
- *
- * <p>This class is immutable, and interoperable with most methods that accept
- * a <code>Number</code>.</p>
- *
- * @author Travis Reeder
- * @author Stephen Colebourne
- * @author Tim O'Brien
- * @author Pete Gieser
- * @since 2.0
- * @version $Id: Fraction.java,v 1.11 2003/08/18 02:22:24 bayard Exp $
- */
- public final class Fraction extends Number implements Serializable, Comparable {
-
- /** Serialization lock, Lang version 2.0 */
- private static final long serialVersionUID = 65382027393090L;
-
- /**
- * <code>Fraction</code> representation of 0.
- */
- public static final Fraction ZERO = new Fraction(0, 1);
- /**
- * <code>Fraction</code> representation of 1.
- */
- public static final Fraction ONE = new Fraction(1, 1);
- /**
- * <code>Fraction</code> representation of 1/2.
- */
- public static final Fraction ONE_HALF = new Fraction(1, 2);
- /**
- * <code>Fraction</code> representation of 1/3.
- */
- public static final Fraction ONE_THIRD = new Fraction(1, 3);
- /**
- * <code>Fraction</code> representation of 2/3.
- */
- public static final Fraction TWO_THIRDS = new Fraction(2, 3);
- /**
- * <code>Fraction</code> representation of 1/4.
- */
- public static final Fraction ONE_QUARTER = new Fraction(1, 4);
- /**
- * <code>Fraction</code> representation of 2/4.
- */
- public static final Fraction TWO_QUARTERS = new Fraction(2, 4);
- /**
- * <code>Fraction</code> representation of 3/4.
- */
- public static final Fraction THREE_QUARTERS = new Fraction(3, 4);
- /**
- * <code>Fraction</code> representation of 1/5.
- */
- public static final Fraction ONE_FIFTH = new Fraction(1, 5);
- /**
- * <code>Fraction</code> representation of 2/5.
- */
- public static final Fraction TWO_FIFTHS = new Fraction(2, 5);
- /**
- * <code>Fraction</code> representation of 3/5.
- */
- public static final Fraction THREE_FIFTHS = new Fraction(3, 5);
- /**
- * <code>Fraction</code> representation of 4/5.
- */
- public static final Fraction FOUR_FIFTHS = new Fraction(4, 5);
-
-
- /**
- * The numerator number part of the fraction (the three in three sevenths).
- */
- private final int numerator;
- /**
- * The denominator number part of the fraction (the seven in three sevenths).
- */
- private final int denominator;
-
- /**
- * Cached output hashCode (class is immutable).
- */
- private transient int hashCode = 0;
- /**
- * Cached output toString (class is immutable).
- */
- private transient String toString = null;
- /**
- * Cached output toProperString (class is immutable).
- */
- private transient String toProperString = null;
-
- /**
- * <p>Constructs a <code>Fraction</code> instance with the 2 parts
- * of a fraction Y/Z.</p>
- *
- * @param numerator the numerator, for example the three in 'three sevenths'
- * @param denominator the denominator, for example the seven in 'three sevenths'
- */
- private Fraction(int numerator, int denominator) {
- super();
- this.numerator = numerator;
- this.denominator = denominator;
- }
-
- /**
- * <p>Creates a <code>Fraction</code> instance with the 2 parts
- * of a fraction Y/Z.</p>
- *
- * <p>Any negative signs are resolved to be on the numerator.</p>
- *
- * @param numerator the numerator, for example the three in 'three sevenths'
- * @param denominator the denominator, for example the seven in 'three sevenths'
- * @return a new fraction instance
- * @throws ArithmeticException if the denomiator is <code>zero</code>
- */
- public static Fraction getFraction(int numerator, int denominator) {
- if (denominator == 0) {
- throw new ArithmeticException("The denominator must not be zero");
- }
- if (denominator < 0) {
- numerator = -numerator;
- denominator = -denominator;
- }
- return new Fraction(numerator, denominator);
- }
-
- /**
- * <p>Creates a <code>Fraction</code> instance with the 3 parts
- * of a fraction X Y/Z.</p>
- *
- * <p>The negative sign must be passed in on the whole number part.</p>
- *
- * @param whole the whole number, for example the one in 'one and three sevenths'
- * @param numerator the numerator, for example the three in 'one and three sevenths'
- * @param denominator the denominator, for example the seven in 'one and three sevenths'
- * @return a new fraction instance
- * @throws ArithmeticException if the denomiator is <code>zero</code>
- * @throws ArithmeticException if the denomiator is negative
- * @throws ArithmeticException if the numerator is negative
- * @throws ArithmeticException if the resulting numerator exceeds
- * <code>Integer.MAX_VALUE</code>
- */
- public static Fraction getFraction(int whole, int numerator, int denominator) {
- if (denominator == 0) {
- throw new ArithmeticException("The denominator must not be zero");
- }
- if (denominator < 0) {
- throw new ArithmeticException("The denominator must not be negative");
- }
- if (numerator < 0) {
- throw new ArithmeticException("The numerator must not be negative");
- }
- double numeratorValue = 0;
- if (whole < 0) {
- numeratorValue = (double) whole * denominator - numerator;
- } else {
- numeratorValue = (double) whole * denominator + numerator;
- }
- if (Math.abs(numeratorValue) > Integer.MAX_VALUE) {
- throw new ArithmeticException("Numerator too large to represent as an Integer.");
- }
- return new Fraction((int) numeratorValue, denominator);
- }
-
- /**
- * <p>Creates a <code>Fraction</code> instance with the 2 parts
- * of a fraction Y/Z.</p>
- *
- * <p>Any negative signs are resolved to be on the numerator.</p>
- *
- * @param numerator the numerator, for example the three in 'three sevenths'
- * @param denominator the denominator, for example the seven in 'three sevenths'
- * @return a new fraction instance, with the numerator and denominator reduced
- * @throws ArithmeticException if the denomiator is <code>zero</code>
- */
- public static Fraction getReducedFraction(int numerator, int denominator) {
- if (denominator == 0) {
- throw new ArithmeticException("The denominator must not be zero");
- }
- if (denominator < 0) {
- numerator = -numerator;
- denominator = -denominator;
- }
- int gcd = greatestCommonDivisor(Math.abs(numerator), denominator);
- return new Fraction(numerator / gcd, denominator / gcd);
- }
-
- /**
- * <p>Creates a <code>Fraction</code> instance from a <code>double</code> value.</p>
- *
- * <p>This method uses the <a href="http://archives.math.utk.edu/articles/atuyl/confrac/">
- * continued fraction algorithm</a>, computing a maximum of
- * 25 convergents and bounding the denominator by 10,000.</p>
- *
- * @param value the double value to convert
- * @return a new fraction instance that is close to the value
- * @throws ArithmeticException if <code>|value| > Integer.MAX_VALUE</code>
- * or <code>value = NaN</code>
- * @throws ArithmeticException if the calculated denomiator is <code>zero</code>
- * @throws ArithmeticException if the the algorithm does not converge
- */
- public static Fraction getFraction(double value) {
- 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");
- }
- 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 a1 = (int) value;
- int a2 = 0;
- double x1 = 1;
- double x2 = 0;
- double y1 = value - a1;
- double y2 = 0;
- double delta1, delta2 = Double.MAX_VALUE;
- double fraction;
- int i = 1;
- // System.out.println("---");
- do {
- delta1 = delta2;
- a2 = (int) (x1 / y1);
- x2 = y1;
- y2 = x1 - a2 * y1;
- numer2 = a1 * numer1 + numer0;
- denom2 = a1 * denom1 + denom0;
- fraction = (double) numer2 / (double) denom2;
- delta2 = Math.abs(value - fraction);
- // System.out.println(numer2 + " " + denom2 + " " + fraction + " " + delta2 + " " + y1);
- a1 = a2;
- x1 = x2;
- y1 = y2;
- numer0 = numer1;
- denom0 = denom1;
- numer1 = numer2;
- denom1 = denom2;
- i++;
- // 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");
- }
- return getReducedFraction((numer0 + wholeNumber * denom0) * sign, denom0);
- }
-
- /**
- * <p>Creates a Fraction from a <code>String</code>.</p>
- *
- * <p>The formats accepted are:</p>
- *
- * <p>
- * <ol>
- * <li><code>double</code> String containing a dot</li>
- * <li>'X Y/Z'</li>
- * <li>'Y/Z'</li>
- * </ol>
- * and a .</p>
- *
- * @param str the string to parse, must not be <code>null</code>
- * @return the new <code>Fraction</code> instance
- * @throws IllegalArgumentException if the string is <code>null</code>
- * @throws NumberFormatException if the number format is invalid
- */
- public static Fraction getFraction(String str) {
- if (str == null) {
- throw new IllegalArgumentException("The string must not be null");
- }
- // parse double format
- int pos = str.indexOf('.');
- if (pos >= 0) {
- return getFraction(Double.parseDouble(str));
- }
-
- // parse X Y/Z format
- pos = str.indexOf(' ');
- if (pos > 0) {
- int whole = Integer.parseInt(str.substring(0, pos));
- str = str.substring(pos + 1);
- pos = str.indexOf('/');
- if (pos < 0) {
- throw new NumberFormatException("The fraction could not be parsed as the format X Y/Z");
- } else {
- int denom = Integer.parseInt(str.substring(pos + 1));
- return getFraction(
- Integer.parseInt(str.substring(0, pos)) + whole * denom,
- denom
- );
- }
- }
-
- // parse Y/Z format
- pos = str.indexOf('/');
- if (pos < 0) {
- // simple whole number
- return getFraction(Integer.parseInt(str), 1);
- } else {
- return getFraction(
- Integer.parseInt(str.substring(0, pos)),
- Integer.parseInt(str.substring(pos + 1))
- );
- }
- }
-
- // Accessors
- //-------------------------------------------------------------------
-
- /**
- * <p>Gets the numerator part of the fraction.</p>
- *
- * <p>This method may return a value greater than the denominator, an
- * improper fraction, such as the seven in 7/4.</p>
- *
- * @return the numerator fraction part
- */
- public int getNumerator() {
- return numerator;
- }
-
- /**
- * <p>Gets the denominator part of the fraction.</p>
- *
- * @return the denominator fraction part
- */
- public int getDenominator() {
- return denominator;
- }
-
- /**
- * <p>Gets the proper numerator, always positive.</p>
- *
- * <p>An improper fraction 7/4 can be resolved into a proper one, 1 3/4.
- * This method returns the 3 from the proper fraction.</p>
- *
- * <p>If the fraction is negative such as -7/4, it can be resolved into
- * -1 3/4, so this method returns the positive proper numerator, 3.</p>
- *
- * @return the numerator fraction part of a proper fraction, always positive
- */
- public int getProperNumerator() {
- return Math.abs(numerator % denominator);
- }
-
- /**
- * <p>Gets the proper whole part of the fraction.</p>
- *
- * <p>An improper fraction 7/4 can be resolved into a proper one, 1 3/4.
- * This method returns the 1 from the proper fraction.</p>
- *
- * <p>If the fraction is negative such as -7/4, it can be resolved into
- * -1 3/4, so this method returns the positive whole part -1.</p>
- *
- * @return the whole fraction part of a proper fraction, that includes the sign
- */
- public int getProperWhole() {
- return numerator / denominator;
- }
-
- // Number methods
- //-------------------------------------------------------------------
-
- /**
- * <p>Gets the fraction as an <code>int</code>. This returns the whole number
- * part of the fraction.</p>
- *
- * @return the whole number fraction part
- */
- public int intValue() {
- return numerator / denominator;
- }
-
- /**
- * <p>Gets the fraction as a <code>long</code>. This returns the whole number
- * part of the fraction.</p>
- *
- * @return the whole number fraction part
- */
- public long longValue() {
- return (long) numerator / denominator;
- }
-
- /**
- * <p>Gets the fraction as a <code>float</code>. This calculates the fraction
- * as the numerator divided by denominator.</p>
- *
- * @return the fraction as a <code>float</code>
- */
- public float floatValue() {
- return ((float) numerator) / ((float) denominator);
- }
-
- /**
- * <p>Gets the fraction as a <code>double</code>. This calculates the fraction
- * as the numerator divided by denominator.</p>
- *
- * @return the fraction as a <code>double</code>
- */
- public double doubleValue() {
- return ((double) numerator) / ((double) denominator);
- }
-
- // Calculations
- //-------------------------------------------------------------------
-
- /**
- * <p>Reduce the fraction to the smallest values for the numerator and
- * denominator, returning the result..</p>
- *
- * @return a new reduce fraction instance, or this if no simplification possible
- */
- public Fraction reduce() {
- int gcd = greatestCommonDivisor(Math.abs(numerator), denominator);
- return Fraction.getFraction(numerator / gcd, denominator / gcd);
- }
-
- /**
- * <p>Gets a fraction that is the invert (1/fraction) of this one.</p>
- *
- * <p>The returned fraction is not reduced.</p>
- *
- * @return a new fraction instance with the numerator and denominator inverted
- * @throws ArithmeticException if the numerator is <code>zero</code>
- */
- public Fraction invert() {
- if (numerator == 0) {
- throw new ArithmeticException("Unable to invert a fraction with a zero numerator");
- }
- return getFraction(denominator, numerator);
- }
-
- /**
- * <p>Gets a fraction that is the negative (-fraction) of this one.</p>
- *
- * <p>The returned fraction is not reduced.</p>
- *
- * @return a new fraction instance with the opposite signed numerator
- */
- public Fraction negate() {
- return getFraction(-numerator, denominator);
- }
-
- /**
- * <p>Gets a fraction that is the positive equivalent of this one.</p>
- * <p>More precisely: <pre>(fraction >= 0 ? this : -fraction)</pre></p>
- *
- * <p>The returned fraction is not reduced.</p>
- *
- * @return <code>this</code> if it is positive, or a new positive fraction
- * instance with the opposite signed numerator
- */
- public Fraction abs() {
- if (numerator >= 0) {
- return this;
- }
- return getFraction(-numerator, denominator);
- }
-
- /**
- * <p>Gets a fraction that is raised to the passed in power.</p>
- *
- * <p>The returned fraction is not reduced.</p>
- *
- * @param power the power to raise the fraction to
- * @return <code>this</code> if the power is one, <code>ONE</code> if the power
- * is zero (even if the fraction equals ZERO) or a new fraction instance
- * raised to the appropriate power
- * @throws ArithmeticException if the resulting numerator or denominator exceeds
- * <code>Integer.MAX_VALUE</code>
- */
- public Fraction pow(int power) {
- if (power == 1) {
- return this;
- } else if (power == 0) {
- return ONE;
- } else {
- double denominatorValue = Math.pow(denominator, power);
- double numeratorValue = Math.pow(numerator, power);
- if (numeratorValue > Integer.MAX_VALUE || denominatorValue > Integer.MAX_VALUE) {
- throw new ArithmeticException("Integer overflow");
- }
- if (power < 0) {
- return getFraction((int) Math.pow(denominator, -power),
- (int) Math.pow(numerator, -power));
- }
- return getFraction((int) Math.pow(numerator, power),
- (int) Math.pow(denominator, power));
- }
- }
-
- /**
- * <p>Gets the greatest common divisor of two numbers.</p>
- *
- * @param number1 a positive number
- * @param number2 a positive number
- * @return the greatest common divisor, never zero
- */
- private static int greatestCommonDivisor(int number1, int number2) {
- int remainder = number1 % number2;
- while (remainder != 0) {
- number1 = number2;
- number2 = remainder;
- remainder = number1 % number2;
- }
- return number2;
- }
-
- // Arithmetic
- //-------------------------------------------------------------------
-
- /**
- * <p>Adds the value of this fraction to another, returning the result in
- * reduced form.</p>
- *
- * @param fraction the fraction to add, must not be <code>null</code>
- * @return a <code>Fraction</code> instance with the resulting values
- * @throws IllegalArgumentException if the fraction is <code>null</code>
- * @throws ArithmeticException if the resulting numerator or denominator exceeds
- * <code>Integer.MAX_VALUE</code>
- */
- public Fraction add(Fraction fraction) {
- if (fraction == null) {
- throw new IllegalArgumentException("The fraction must not be null");
- }
- if (numerator == 0) {
- return fraction;
- }
- if (fraction.numerator == 0) {
- return this;
- }
- // Compute lcd explicitly to limit overflow
- int gcd = greatestCommonDivisor(Math.abs(fraction.denominator), Math.abs(denominator));
- int thisResidue = denominatorgcd;
- int thatResidue = fraction.denominatorgcd;
- double denominatorValue = Math.abs((double) gcd * thisResidue * thatResidue);
- double numeratorValue = (double) numerator * thatResidue + fraction.numerator * thisResidue;
- if (Math.abs(numeratorValue) > Integer.MAX_VALUE ||
- Math.abs(denominatorValue) > Integer.MAX_VALUE) {
- throw new ArithmeticException("Integer overflow");
- }
- return Fraction.getReducedFraction((int) numeratorValue, (int) denominatorValue);
- }
-
- /**
- * <p>Subtracts the value of another fraction from the value of this one,
- * returning the result in reduced form.</p>
- *
- * @param fraction the fraction to subtract, must not be <code>null</code>
- * @return a <code>Fraction</code> instance with the resulting values
- * @throws IllegalArgumentException if the fraction is <code>null</code>
- * @throws ArithmeticException if the resulting numerator or denominator exceeds
- * <code>Integer.MAX_VALUE</code>
- */
- public Fraction subtract(Fraction fraction) {
- if (fraction == null) {
- throw new IllegalArgumentException("The fraction must not be null");
- }
- return add(fraction.negate());
- }
-
- /**
- * <p>Multiplies the value of this fraction by another, returning the result
- * in reduced form.</p>
- *
- * @param fraction the fraction to multipy by, must not be <code>null</code>
- * @return a <code>Fraction</code> instance with the resulting values
- * @throws IllegalArgumentException if the fraction is <code>null</code>
- * @throws ArithmeticException if the resulting numerator or denominator exceeds
- * <code>Integer.MAX_VALUE</code>
- */
- public Fraction multiplyBy(Fraction fraction) {
- if (fraction == null) {
- throw new IllegalArgumentException("The fraction must not be null");
- }
- if (numerator == 0 || fraction.numerator == 0) {
- return ZERO;
- }
- double numeratorValue = (double) numerator * fraction.numerator;
- double denominatorValue = (double) denominator * fraction.denominator;
- if (Math.abs(numeratorValue) > Integer.MAX_VALUE ||
- Math.abs(denominatorValue) > Integer.MAX_VALUE) {
- throw new ArithmeticException("Integer overflow");
- }
- return getReducedFraction((int) numeratorValue, (int) denominatorValue);
- }
-
- /**
- * <p>Divide the value of this fraction by another, returning the result
- * in reduced form.</p>
- *
- * @param fraction the fraction to divide by, must not be <code>null</code>
- * @return a <code>Fraction</code> instance with the resulting values
- * @throws IllegalArgumentException if the fraction is <code>null</code>
- * @throws ArithmeticException if the fraction to divide by is zero
- * @throws ArithmeticException if the resulting numerator or denominator exceeds
- * <code>Integer.MAX_VALUE</code>
- */
- public Fraction divideBy(Fraction fraction) {
- if (fraction == null) {
- throw new IllegalArgumentException("The fraction must not be null");
- }
- if (fraction.numerator == 0) {
- throw new ArithmeticException("The fraction to divide by must not be zero");
- }
- if (numerator == 0) {
- return ZERO;
- }
- double numeratorValue = (double) numerator * fraction.denominator;
- double denominatorValue = (double) denominator * fraction.numerator;
- if (Math.abs(numeratorValue) > Integer.MAX_VALUE ||
- Math.abs(denominatorValue) > Integer.MAX_VALUE) {
- throw new ArithmeticException("Integer overflow");
- }
- return getReducedFraction((int) numeratorValue, (int) denominatorValue);
- }
-
- // Basics
- //-------------------------------------------------------------------
-
- /**
- * <p>Compares this fraction to another object to test if they are equal.</p>.
- *
- * <p>To be equal, both values must be equal. Thus 2/4 is not equal to 1/2.</p>
- *
- * @param obj the reference object with which to compare
- * @return <code>true</code> if this object is equal
- */
- public boolean equals(Object obj) {
- if (obj == this) {
- return true;
- }
- if (obj instanceof Fraction == false) {
- return false;
- }
- Fraction other = (Fraction) obj;
- return (numerator == other.numerator &&
- denominator == other.denominator);
- }
-
- /**
- * <p>Gets a hashCode for the fraction.</p>
- *
- * @return a hash code value for this object
- */
- public int hashCode() {
- if (hashCode == 0) {
- hashCode = 17;
- hashCode = 37 * hashCode + numerator;
- hashCode = 37 * hashCode + denominator;
- }
- return hashCode;
- }
-
- /**
- * <p>Compares this object to another based on size.</p>
- *
- * @param object the object to compare to
- * @return -1 if this is less, 0 if equal, +1 if greater
- * @throws ClassCastException if the object is not a <code>Fraction</code>
- * @throws NullPointerException if the object is <code>null</code>
- */
- public int compareTo(Object object) {
- Fraction other = (Fraction) object;
- if (numerator == other.numerator && denominator == other.denominator) {
- return 0;
- }
-
- // otherwise see which is less
- long first = (long) numerator * (long) other.denominator;
- long second = (long) other.numerator * (long) denominator;
- if (first == second) {
- return 0;
- } else if (first < second) {
- return -1;
- } else {
- return 1;
- }
- }
-
- /**
- * <p>Gets the fraction as a <code>String</code>.</p>
- *
- * <p>The format used is '<i>numerator</i>/<i>denominator</i>' always.
- *
- * @return a <code>String</code> form of the fraction
- */
- public String toString() {
- if (toString == null) {
- toString = new StringBuffer(32)
- .append(numerator)
- .append('/')
- .append(denominator).toString();
- }
- return toString;
- }
-
- /**
- * <p>Gets the fraction as a proper <code>String</code> in the format X Y/Z.</p>
- *
- * <p>The format used in '<i>wholeNumber</i> <i>numerator</i>/<i>denominator</i>'.
- * If the whole number is zero it will be ommitted. If the numerator is zero,
- * only the whole number is returned.</p>
- *
- * @return a <code>String</code> form of the fraction
- */
- public String toProperString() {
- if (toProperString == null) {
- if (numerator == 0) {
- toProperString = "0";
- } else if (numerator == denominator) {
- toProperString = "1";
- } else if (Math.abs(numerator) > denominator) {
- int properNumerator = getProperNumerator();
- if (properNumerator == 0) {
- toProperString = Integer.toString(getProperWhole());
- } else {
- toProperString = new StringBuffer(32)
- .append(getProperWhole()).append(' ')
- .append(properNumerator).append('/')
- .append(denominator).toString();
- }
- } else {
- toProperString = new StringBuffer(32)
- .append(numerator).append('/')
- .append(denominator).toString();
- }
- }
- return toProperString;
- }
-
- }