Package tech.units.indriya

Class AbstractQuantity<Q extends javax.measure.Quantity<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:
    NumberQuantity, 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:
    1.12, Jul 21, 2020
    Author:
    Werner Keil, Andi Huber
    See Also:
    Serialized Form

    • Nested Class Summary

      • Nested classes/interfaces inherited from interface javax.measure.Quantity

        javax.measure.Quantity.Scale

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static javax.measure.Quantity<javax.measure.quantity.Dimensionless> NONE
      Holds a dimensionless quantity of none (exact).
      static javax.measure.Quantity<javax.measure.quantity.Dimensionless> ONE
      Holds a dimensionless quantity of one (exact).

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      protected AbstractQuantity​(javax.measure.Unit<Q> unit)
      Constructor.
      protected AbstractQuantity​(javax.measure.Unit<Q> unit, javax.measure.Quantity.Scale sca)
      Constructor.

    • Method Summary

      Modifier and Type Method Description
      <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)
      FIXME[220] update java-doc Compares this quantity to the specified quantity.
      <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
      boolean equals​(Object obj)
      Compares this quantity against the specified object for strict equality (same unit and same amount).
      javax.measure.Quantity.Scale getScale()
      Returns the absolute or relative scale.
      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.
      <T extends javax.measure.Quantity<T>>
      ComparableQuantity<T>      		 inverse​(Class<T> quantityClass)
      invert and already cast to defined quantityClass
      boolean isEquivalentTo​(javax.measure.Quantity<Q> that)
      Compares two instances of Quantity <Q>, 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.
      <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
      protected NumberSystem numberSystem()  
      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> anotherUnit)
      Returns this quantity after conversion to specified unit.
      String toString()
      Returns the String representation of this quantity.

      • Methods inherited from interface javax.measure.Quantity

        negate, toSystemUnit

    • Field Detail

      • 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 Detail

      • AbstractQuantity

        protected AbstractQuantity​(javax.measure.Unit<Q> unit,
                           javax.measure.Quantity.Scale sca)
        Constructor.
        Parameters:
        unit - a unit
        sca - the scale, absolute or relative

      • AbstractQuantity

        protected AbstractQuantity​(javax.measure.Unit<Q> unit)
        Constructor. Applies ABSOLUTE Scale if none was given.
        Parameters:
        unit - a unit

    • Method Detail

      • 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.

      • getScale

        public javax.measure.Quantity.Scale getScale()
        Returns the absolute or relative scale.
        Specified by:
        getScale in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>
        Returns:
        the scale.

      • to

        public ComparableQuantity<Q> to​(javax.measure.Unit<Q> anotherUnit)
        Returns this quantity after conversion to specified unit. The default implementation returns NumberQuantity.of(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:
        anotherUnit - the unit in which the returned quantity 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.

      • compareTo

        public int compareTo​(javax.measure.Quantity<Q> that)
        FIXME[220] update java-doc Compares this quantity to the specified quantity. The default implementation compares the AbstractQuantity#doubleValue(Unit) of both this quantity and the specified quantity stated in the same unit (this quantity'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 quantity 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 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()) && this.getLevel().equals(obj.getLevel() && this.getValue().equals(obj.getValue())

      • hashCode

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

      • 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:
        SimpleQuantityFormat.getInstance().format(this)

      • 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:
        QuantityOperations, 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.
        Quantity proportion = AbstractQuantity.parse("0.234").asType(Dimensionless.class);

        Note: This method handles only 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)