-package tim.prune.jpeg.drew;\r
-\r
-/**\r
- * Immutable class for holding a rational number without loss of precision.\r
- * Based on Drew Noakes' Metadata extractor at http://drewnoakes.com\r
- */\r
-public class Rational\r
-{\r
- /** Holds the numerator */\r
- private final int _numerator;\r
-\r
- /** Holds the denominator */\r
- private final int _denominator;\r
-\r
- /**\r
- * Constructor\r
- * @param inNumerator numerator of fraction (upper number)\r
- * @param inDenominator denominator of fraction (lower number)\r
- */\r
- public Rational(int inNumerator, int inDenominator)\r
- {\r
- // Could throw exception if denominator is zero\r
- _numerator = inNumerator;\r
- _denominator = inDenominator;\r
- }\r
-\r
-\r
- /**\r
- * @return the value of the specified number as a <code>double</code>.\r
- * This may involve rounding.\r
- */\r
- public double doubleValue()\r
- {\r
- if (_denominator == 0) return 0.0;\r
- return (double)_numerator / (double)_denominator;\r
- }\r
-\r
- /**\r
- * @return the value of the specified number as an <code>int</code>.\r
- * This may involve rounding or truncation.\r
- */\r
- public final int intValue()\r
- {\r
- if (_denominator == 0) return 0;\r
- return _numerator / _denominator;\r
- }\r
-\r
- /**\r
- * @return the denominator.\r
- */\r
- public final int getDenominator()\r
- {\r
- return _denominator;\r
- }\r
-\r
- /**\r
- * @return the numerator.\r
- */\r
- public final int getNumerator()\r
- {\r
- return _numerator;\r
- }\r
-\r
- /**\r
- * Checks if this rational number is an Integer, either positive or negative\r
- * @return true if an integer\r
- */\r
- public boolean isInteger()\r
- {\r
- // number is integer if the denominator is 1, or if the remainder is zero\r
- return (_denominator == 1\r
- || (_denominator != 0 && (_numerator % _denominator == 0)));\r
- }\r
-\r
-\r
- /**\r
- * @return a string representation of the object of form <code>numerator/denominator</code>.\r
- */\r
- public String toString()\r
- {\r
- return "" + _numerator + "/" + _denominator;\r
- }\r
-\r
-\r
- /**\r
- * Compares two <code>Rational</code> instances, returning true if they are equal\r
- * @param inOther the Rational to compare this instance to.\r
- * @return true if instances are equal, otherwise false.\r
- */\r
- public boolean equals(Rational inOther)\r
- {\r
- // Could also attempt to simplify fractions to lowest common denominator before compare\r
- return _numerator == inOther._numerator && _denominator == inOther._denominator;\r
- }\r
-}
\ No newline at end of file
+package tim.prune.jpeg.drew;
+
+/**
+ * Immutable class for holding a rational number without loss of precision.
+ * Based on Drew Noakes' Metadata extractor at https://drewnoakes.com
+ */
+public class Rational
+{
+ /** Holds the numerator */
+ private final long _numerator;
+
+ /** Holds the denominator */
+ private final long _denominator;
+
+ /**
+ * Creates a new (immutable) instance of Rational.
+ */
+ public Rational(long numerator, long denominator)
+ {
+ _numerator = numerator;
+ _denominator = denominator;
+ }
+
+ /**
+ * @return the value of the specified number as a <code>double</code>.
+ * This may involve rounding.
+ */
+ public double doubleValue()
+ {
+ if (_denominator == 0L) return 0.0;
+ return (double)_numerator / (double)_denominator;
+ }
+
+ /**
+ * Returns the value of the specified number as an <code>int</code>.
+ */
+ public final int intValue()
+ {
+ return (int) longValue();
+ }
+
+ /**
+ * Returns the value of the specified number as a <code>long</code>.
+ * This may involve rounding or truncation.
+ * If the denominator is 0, returns 0 to avoid dividing by 0.
+ */
+ public final long longValue()
+ {
+ if (_denominator == 0L) return 0L;
+ return _numerator / _denominator;
+ }
+
+ /** Returns the denominator */
+ public final long getDenominator()
+ {
+ return _denominator;
+ }
+
+ /** Returns the numerator */
+ public final long getNumerator()
+ {
+ return _numerator;
+ }
+
+ /**
+ * @return the value of the specified number as a positive <code>double</code>.
+ * Prevents interpretation of 32 bit numbers as negative, and forces a positive answer.
+ * Needed?
+ */
+ public double convertToPositiveValue()
+ {
+ if (_denominator == 0L) return 0.0;
+ double numeratorDbl = _numerator;
+ double denomDbl = _denominator;
+ if (_numerator >= 0L) {
+ // Numerator is positive (but maybe denominator isn't?)
+ return numeratorDbl / denomDbl;
+ }
+ // Add 2^32 to negative doubles to make them positive
+ final double correction = Math.pow(2.0, 32);
+ numeratorDbl += correction;
+ if (_denominator < 0L) {
+ denomDbl += correction;
+ }
+ return numeratorDbl / denomDbl;
+ }
+
+ /**
+ * Returns a string representation of the object of form <code>numerator/denominator</code>.
+ */
+ @Override
+ public String toString()
+ {
+ return "" + _numerator + "/" + _denominator;
+ }
+
+ /**
+ * Compares two {@link Rational} instances, returning true if they are mathematically
+ * equivalent.
+ *
+ * @param obj the {@link Rational} to compare this instance to.
+ * @return true if instances are mathematically equivalent, otherwise false. Will also
+ * give false if <code>obj</code> is not an instance of {@link Rational}.
+ */
+ @Override
+ public boolean equals( Object obj)
+ {
+ if (obj==null || !(obj instanceof Rational))
+ return false;
+ Rational that = (Rational) obj;
+ return this.doubleValue() == that.doubleValue();
+ }
+}
projects / GpsPrune.git / blobdiff