Package tech.units.indriya

Class AbstractQuantity<Q extends javax.measure.Quantity<Q>>

java.lang.Object
tech.units.indriya.AbstractQuantity<Q>
All Implemented Interfaces:
Serializable, Comparable<javax.measure.Quantity<Q>>, javax.measure.Quantity<Q>, ComparableQuantity<Q>, tech.uom.lib.common.function.QuantityConverter<Q>, tech.uom.lib.common.function.UnitSupplier<Q>, tech.uom.lib.common.function.ValueSupplier<Number>
Direct Known Subclasses:
BigIntegerQuantity, ByteQuantity, DecimalQuantity, DoubleQuantity, FloatQuantity, IntegerQuantity, LongQuantity, NumberQuantity, ShortQuantity, TemporalQuantity, TimeUnitQuantity
public abstract class AbstractQuantity<Q extends javax.measure.Quantity<Q>> extends Object implements ComparableQuantity<Q>, tech.uom.lib.common.function.UnitSupplier<Q>, tech.uom.lib.common.function.ValueSupplier<Number>

This class represents the immutable result of a scalar measurement stated in a known unit.

To avoid any loss of precision, known exact quantities (e.g. physical constants) should not be created from double constants but from their decimal representation.
public static final Quantity<Velocity> C = NumberQuantity.parse("299792458 m/s").asType(Velocity.class); // Speed of Light (exact).

Quantities can be converted to different units.
Quantity<Velocity> milesPerHour = C.to(MILES_PER_HOUR); // Use double implementation (fast). System.out.println(milesPerHour); > 670616629.3843951 m/h

Applications may sub-class AbstractQuantity for particular quantity types.
// Quantity of type Mass based on double primitive types.
public class MassAmount extends AbstractQuantity<Mass> {
private final double kilograms; // Internal SI representation.
private Mass(double kg) { kilograms = kg; }
public static Mass of(double value, Unit<Mass> unit) {
return new Mass(unit.getConverterTo(SI.KILOGRAM).convert(value));
}
public Unit<Mass> getUnit() { return SI.KILOGRAM; }
public Double getValue() { return kilograms; }
...
}

// Complex numbers measurements.
public class ComplexQuantity <Q extends Quantity>extends AbstractQuantity <Q>{
public Complex getValue() { ... } // Assuming Complex is a Number.
...
}

// Specializations of complex numbers quantities.
public final class Current extends ComplexQuantity<ElectricCurrent> {...}
public final class Tension extends ComplexQuantity<ElectricPotential> {...}

All instances of this class shall be immutable.

Since:
1.0
Version:
1.3, April 13, 2018
See Also:

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    protected static final class 
    AbstractQuantity.Equalizer
    Utility class for number comparison and equality

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final javax.measure.Quantity<javax.measure.quantity.Dimensionless>
    NONE
    Holds a dimensionless quantity of none (exact).
    static final javax.measure.Quantity<javax.measure.quantity.Dimensionless>
    ONE
    Holds a dimensionless quantity of one (exact).
    private static final long
    serialVersionUID
     
    private final javax.measure.Unit<Q>
    unit
     

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    AbstractQuantity(javax.measure.Unit<Q> unit)
    constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    final <T extends javax.measure.Quantity<T>>
    ComparableQuantity<T>
    asType(Class<T> type)
    Casts this quantity to a parameterized quantity of specified nature or throw a ClassCastException if the dimension of the specified quantity and its unit's dimension do not match.
    int
    compareTo(javax.measure.Quantity<Q> that)
    Compares this measure to the specified Measurement quantity.
    abstract BigDecimal
    decimalValue(javax.measure.Unit<Q> unit)
     
    <T extends javax.measure.Quantity<T>, E extends javax.measure.Quantity<E>>
    ComparableQuantity<E>
    divide(javax.measure.Quantity<T> that, Class<E> asTypeQuantity)
    Multiply and cast the ComparableQuantity
    abstract double
    doubleValue(javax.measure.Unit<Q> unit)
     
    boolean
    equals(Object obj)
    Compares this quantity against the specified object for strict equality (same unit and same amount).
    boolean
    equals(AbstractQuantity<Q> that, double epsilon, javax.measure.Unit<Q> epsilonUnit)
    Compares this quantity and the specified quantity to the given accuracy.
    protected final float
    floatValue(javax.measure.Unit<Q> unit)
     
    javax.measure.Unit<Q>
    getUnit()
    Returns the measurement unit.
    abstract Number
    getValue()
    Returns the numeric value of the quantity.
    protected boolean
    hasFraction(double value)
     
    protected boolean
    hasFraction(BigDecimal value)
     
    int
    hashCode()
    Returns the hash code for this quantity.
    final int
    intValue(javax.measure.Unit<Q> unit)
     
    <T extends javax.measure.Quantity<T>>
    ComparableQuantity<T>
    inverse(Class<T> quantityClass)
    invert and already cast to defined quantityClass
    abstract boolean
    isBig()
     
    boolean
    isEquivalentOf(javax.measure.Quantity<Q> that)
    Compares two instances of , doing the conversion of unit if necessary.
    boolean
    isGreaterThan(javax.measure.Quantity<Q> that)
    Compares two instances of .
    boolean
    isGreaterThanOrEqualTo(javax.measure.Quantity<Q> that)
    Compares two instances of , doing the conversion of unit if necessary.
    boolean
    isLessThan(javax.measure.Quantity<Q> that)
    Compares two instances of , doing the conversion of unit if necessary.
    boolean
    isLessThanOrEqualTo(javax.measure.Quantity<Q> that)
    Compares two instances of , doing the conversion of unit if necessary.
    protected long
    longValue(javax.measure.Unit<Q> unit)
     
    <T extends javax.measure.Quantity<T>, E extends javax.measure.Quantity<E>>
    ComparableQuantity<E>
    multiply(javax.measure.Quantity<T> that, Class<E> asTypeQuantity)
    Divide and cast the ComparableQuantity
    static javax.measure.Quantity<?>
    parse(CharSequence csq)
    Returns the quantity of unknown type corresponding to the specified representation.
    ComparableQuantity<Q>
    to(javax.measure.Unit<Q> unit)
    Returns this quantity after conversion to specified unit.
    String
    toString()
    Returns the String representation of this quantity.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

    Methods inherited from interface tech.units.indriya.ComparableQuantity

    add, divide, divide, inverse, multiply, multiply, subtract

  • Field Details

    • serialVersionUID

      private static final long serialVersionUID
      See Also:

    • unit

      private final javax.measure.Unit<Q extends javax.measure.Quantity<Q>> unit

    • NONE

      public static final javax.measure.Quantity<javax.measure.quantity.Dimensionless> NONE
      Holds a dimensionless quantity of none (exact).

    • ONE

      public static final javax.measure.Quantity<javax.measure.quantity.Dimensionless> ONE
      Holds a dimensionless quantity of one (exact).

  • Constructor Details

    • AbstractQuantity

      protected AbstractQuantity(javax.measure.Unit<Q> unit)
      constructor.

  • Method Details

    • getValue

      public abstract Number getValue()
      Returns the numeric value of the quantity.
      Specified by:
      getValue in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>
      Specified by:
      getValue in interface tech.uom.lib.common.function.ValueSupplier<Q extends javax.measure.Quantity<Q>>
      Returns:
      the quantity value.

    • getUnit

      public javax.measure.Unit<Q> getUnit()
      Returns the measurement unit.
      Specified by:
      getUnit in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>
      Specified by:
      getUnit in interface tech.uom.lib.common.function.UnitSupplier<Q extends javax.measure.Quantity<Q>>
      Returns:
      the measurement unit.

    • to

      public ComparableQuantity<Q> to(javax.measure.Unit<Q> unit)
      Returns this quantity after conversion to specified unit. The default implementation returns Measure.valueOf(doubleValue(unit), unit) . If this quantity is already stated in the specified unit, then this quantity is returned and no conversion is performed.
      Specified by:
      to in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Specified by:
      to in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>
      Specified by:
      to in interface tech.uom.lib.common.function.QuantityConverter<Q extends javax.measure.Quantity<Q>>
      Parameters:
      unit - the unit in which the returned measure is stated.
      Returns:
      this quantity or a new quantity equivalent to this quantity stated in the specified unit.
      Throws:
      ArithmeticException - if the result is inexact and the quotient has a non-terminating decimal expansion.
      See Also:
      • Quantity.to(Unit)

    • isGreaterThan

      public boolean isGreaterThan(javax.measure.Quantity<Q> that)
      Description copied from interface: ComparableQuantity
      Compares two instances of . Conversion of unit can happen if necessary
      Specified by:
      isGreaterThan in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the quantity<Q> to be compared with this instance.
      Returns:
      true if that > this.

    • isGreaterThanOrEqualTo

      public boolean isGreaterThanOrEqualTo(javax.measure.Quantity<Q> that)
      Description copied from interface: ComparableQuantity
      Compares two instances of , doing the conversion of unit if necessary.
      Specified by:
      isGreaterThanOrEqualTo in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the quantity<Q> to be compared with this instance.
      Returns:
      true if that >= this.

    • isLessThan

      public boolean isLessThan(javax.measure.Quantity<Q> that)
      Description copied from interface: ComparableQuantity
      Compares two instances of , doing the conversion of unit if necessary.
      Specified by:
      isLessThan in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the quantity<Q> to be compared with this instance.
      Returns:
      true if that < this.

    • isLessThanOrEqualTo

      public boolean isLessThanOrEqualTo(javax.measure.Quantity<Q> that)
      Description copied from interface: ComparableQuantity
      Compares two instances of , doing the conversion of unit if necessary.
      Specified by:
      isLessThanOrEqualTo in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the quantity<Q> to be compared with this instance.
      Returns:
      true if that < this.

    • isEquivalentOf

      public boolean isEquivalentOf(javax.measure.Quantity<Q> that)
      Description copied from interface: ComparableQuantity
      Compares two instances of , doing the conversion of unit if necessary.
      Specified by:
      isEquivalentOf in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - the quantity<Q> to be compared with this instance.
      Returns:
      true if that < this.

    • compareTo

      public int compareTo(javax.measure.Quantity<Q> that)
      Compares this measure to the specified Measurement quantity. The default implementation compares the doubleValue(Unit) of both this measure and the specified Measurement stated in the same unit (this measure's unit).
      Specified by:
      compareTo in interface Comparable<Q extends javax.measure.Quantity<Q>>
      Returns:
      a negative integer, zero, or a positive integer as this measure is less than, equal to, or greater than the specified Measurement quantity.

    • equals

      public boolean equals(Object obj)
      Compares this quantity against the specified object for strict equality (same unit and same amount).

      Similarly to the BigDecimal.equals(java.lang.Object) method which consider 2.0 and 2.00 as different objects because of different internal scales, quantities such as Quantities.getQuantity(3.0, KILOGRAM) Quantities.getQuantity(3, KILOGRAM) and Quantities.getQuantity("3 kg") might not be considered equals because of possible differences in their implementations.

      To compare quantities stated using different units or using different amount implementations the compareTo or

      invalid reference 
      equals(Quantity, epsilon, epsilonUnit)
      methods should be used.

      Overrides:
      equals in class Object
      Parameters:
      obj - the object to compare with.
      Returns:
      this.getUnit.equals(obj.getUnit()) invalid input: '&'invalid input: '&' this.getValue().equals(obj.getValue())

    • equals

      public boolean equals(AbstractQuantity<Q> that, double epsilon, javax.measure.Unit<Q> epsilonUnit)
      Compares this quantity and the specified quantity to the given accuracy. Quantities are considered approximately equals if their absolute differences when stated in the same specified unit is less than the specified epsilon.
      Parameters:
      that - the quantity to compare with.
      epsilon - the absolute error stated in epsilonUnit.
      epsilonUnit - the epsilon unit.
      Returns:
      abs(this.doubleValue(epsilonUnit) - that.doubleValue(epsilonUnit)) <= epsilon

    • hashCode

      public int hashCode()
      Returns the hash code for this quantity.
      Overrides:
      hashCode in class Object
      Returns:
      the hash code value.

    • isBig

      public abstract boolean isBig()

    • toString

      public String toString()
      Returns the String representation of this quantity. The string produced for a given quantity is always the same; it is not affected by locale. This means that it can be used as a canonical string representation for exchanging quantity, or as a key for a Hashtable, etc. Locale-sensitive quantity formatting and parsing is handled by the QuantityFormat implementations and its subclasses.
      Overrides:
      toString in class Object
      Returns:
      UnitFormat.getInternational().format(this)

    • decimalValue

      public abstract BigDecimal decimalValue(javax.measure.Unit<Q> unit) throws ArithmeticException
      Throws:
      ArithmeticException

    • doubleValue

      public abstract double doubleValue(javax.measure.Unit<Q> unit) throws ArithmeticException
      Throws:
      ArithmeticException

    • intValue

      public final int intValue(javax.measure.Unit<Q> unit) throws ArithmeticException
      Throws:
      ArithmeticException

    • longValue

      protected long longValue(javax.measure.Unit<Q> unit) throws ArithmeticException
      Throws:
      ArithmeticException

    • floatValue

      protected final float floatValue(javax.measure.Unit<Q> unit)

    • divide

      public <T extends javax.measure.Quantity<T>, E extends javax.measure.Quantity<E>> ComparableQuantity<E> divide(javax.measure.Quantity<T> that, Class<E> asTypeQuantity)
      Description copied from interface: ComparableQuantity
      Multiply and cast the ComparableQuantity
      Specified by:
      divide in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - quantity to be multiplied
      asTypeQuantity - quantity to be converted
      Returns:
      the QuantityOperations multiplied and converted
      See Also:
      • Quantity.divide(Quantity)
      • Quantity.asType(Class)

    • multiply

      public <T extends javax.measure.Quantity<T>, E extends javax.measure.Quantity<E>> ComparableQuantity<E> multiply(javax.measure.Quantity<T> that, Class<E> asTypeQuantity)
      Description copied from interface: ComparableQuantity
      Divide and cast the ComparableQuantity
      Specified by:
      multiply in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      that - quantity to be divided
      asTypeQuantity - quantity to be converted
      Returns:
      the QuantityOperations multiplied and converted
      See Also:
      • invalid reference 
        QuantityOperations
      • invalid reference 
        QuantityOperations#of(Quantity, Class)
      • Quantity.asType(Class)
      • Quantity.multiply(Quantity)

    • inverse

      public <T extends javax.measure.Quantity<T>> ComparableQuantity<T> inverse(Class<T> quantityClass)
      Description copied from interface: ComparableQuantity
      invert and already cast to defined quantityClass
      Specified by:
      inverse in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      quantityClass - Quantity to be converted
      See Also:
      • Quantity.inverse()
      • Quantity.asType(Class)

    • asType

      public final <T extends javax.measure.Quantity<T>> ComparableQuantity<T> asType(Class<T> type) throws ClassCastException
      Casts this quantity to a parameterized quantity of specified nature or throw a ClassCastException if the dimension of the specified quantity and its unit's dimension do not match. For example:
      Quantity length = AbstractQuantity.parse("2 km").asType(Length.class);
      Specified by:
      asType in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>
      Specified by:
      asType in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>
      Parameters:
      type - the quantity class identifying the nature of the quantity.
      Returns:
      this quantity parameterized with the specified type.
      Throws:
      ClassCastException - if the dimension of this unit is different from the specified quantity dimension.
      UnsupportedOperationException - if the specified quantity class does not have a public static field named "UNIT" holding the SI unit for the quantity.
      See Also:
      • Unit.asType(Class)

    • parse

      public static javax.measure.Quantity<?> parse(CharSequence csq)
      Returns the quantity of unknown type corresponding to the specified representation. This method can be used to parse dimensionless quantities.
      Quatity proportion = AbstractQuantity.parse("0.234").asType(Dimensionless.class);

      Note: This method handles only

      invalid reference 
      standard
      unit format. Locale-sensitive quantity parsing is currently not supported.

      Parameters:
      csq - the decimal value and its unit (if any) separated by space(s).
      Returns:
      QuantityFormat.getInstance().parse(csq)

    • hasFraction

      protected boolean hasFraction(double value)

    • hasFraction

      protected boolean hasFraction(BigDecimal value)