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 quantity 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 number quantities.
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.
| Modifier and Type | Field and 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).
|
| Modifier | Constructor and Description |
|---|---|
protected |
AbstractQuantity(javax.measure.Unit<Q> unit)
Constructor.
|
protected |
AbstractQuantity(javax.measure.Unit<Q> unit,
javax.measure.Quantity.Scale sca)
Constructor.
|
| Modifier and Type | Method and Description |
|---|---|
<T extends javax.measure.Quantity<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>> |
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(BigDecimal value) |
protected boolean |
hasFraction(double value) |
int |
hashCode()
Returns the hash code for this quantity.
|
<T extends javax.measure.Quantity<T>> |
inverse(Class<T> quantityClass)
invert and already cast to defined quantityClass
|
boolean |
isEquivalentTo(javax.measure.Quantity<Q> that) |
boolean |
isGreaterThan(javax.measure.Quantity<Q> that)
Compares two instances of
|
boolean |
isGreaterThanOrEqualTo(javax.measure.Quantity<Q> that)
Compares two instances of
|
boolean |
isLessThan(javax.measure.Quantity<Q> that)
Compares two instances of
|
boolean |
isLessThanOrEqualTo(javax.measure.Quantity<Q> that)
Compares two instances of
|
<T extends javax.measure.Quantity<T>,E extends javax.measure.Quantity<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. |
clone, finalize, getClass, notify, notifyAll, wait, wait, waitpublic static final javax.measure.Quantity<javax.measure.quantity.Dimensionless> NONE
public static final javax.measure.Quantity<javax.measure.quantity.Dimensionless> ONE
protected AbstractQuantity(javax.measure.Unit<Q> unit, javax.measure.Quantity.Scale sca)
unit - a unitsca - the scale, absolute or relativeprotected AbstractQuantity(javax.measure.Unit<Q> unit)
ABSOLUTE Scale if none was given.unit - a unitpublic javax.measure.Quantity.Scale getScale()
public ComparableQuantity<Q> to(javax.measure.Unit<Q> anotherUnit)
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.to in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>to in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>to in interface tech.uom.lib.common.function.QuantityConverter<Q extends javax.measure.Quantity<Q>>anotherUnit - the unit in which the returned quantity is stated.ArithmeticException - if the result is inexact and the quotient has a non-terminating decimal expansion.Quantity.to(Unit)public boolean isGreaterThan(javax.measure.Quantity<Q> that)
ComparableQuantityisGreaterThan in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>that - the quantity<Q> to be compared with this instance.true if that > this.public boolean isGreaterThanOrEqualTo(javax.measure.Quantity<Q> that)
ComparableQuantityisGreaterThanOrEqualTo in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>that - the quantity<Q> to be compared with this instance.true if that >= this.public boolean isLessThan(javax.measure.Quantity<Q> that)
ComparableQuantityisLessThan in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>that - the quantity<Q> to be compared with this instance.true if that < this.public boolean isLessThanOrEqualTo(javax.measure.Quantity<Q> that)
ComparableQuantityisLessThanOrEqualTo in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>that - the quantity<Q> to be compared with this instance.true if that < this.public boolean isEquivalentTo(javax.measure.Quantity<Q> that)
public int compareTo(javax.measure.Quantity<Q> that)
AbstractQuantity#doubleValue(Unit)
of both this quantity and the specified quantity stated in the same unit (this quantity's unit).compareTo in interface Comparable<javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>>tech.uom.lib.common.util.NaturalQuantityComparator NaturalQuantityComparator}public boolean equals(Object obj)
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.
public int hashCode()
public String toString()
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.public <T extends javax.measure.Quantity<T>,E extends javax.measure.Quantity<E>> ComparableQuantity<E> divide(javax.measure.Quantity<T> that, Class<E> asTypeQuantity)
ComparableQuantityComparableQuantitydivide in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>that - quantity to be multipliedasTypeQuantity - quantity to be convertedQuantity.divide(Quantity),
Quantity.asType(Class)public <T extends javax.measure.Quantity<T>,E extends javax.measure.Quantity<E>> ComparableQuantity<E> multiply(javax.measure.Quantity<T> that, Class<E> asTypeQuantity)
ComparableQuantityComparableQuantitymultiply in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>that - quantity to be dividedasTypeQuantity - quantity to be convertedQuantityOperations,
QuantityOperations#of(Quantity, Class),
Quantity.asType(Class),
Quantity.multiply(Quantity)public <T extends javax.measure.Quantity<T>> ComparableQuantity<T> inverse(Class<T> quantityClass)
ComparableQuantityinverse in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>quantityClass - Quantity to be convertedQuantity.inverse(),
Quantity.asType(Class)public final <T extends javax.measure.Quantity<T>> ComparableQuantity<T> asType(Class<T> type) throws ClassCastException
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);
asType in interface javax.measure.Quantity<Q extends javax.measure.Quantity<Q>>asType in interface ComparableQuantity<Q extends javax.measure.Quantity<Q>>type - the quantity class identifying the nature of the quantity.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.Unit.asType(Class)public static javax.measure.Quantity<?> parse(CharSequence csq)
Quantity proportion = AbstractQuantity.parse("0.234").asType(Dimensionless.class);
Note: This method handles only standard unit format. Locale-sensitive or mixed quantity parsing is currently not
supported by this class. If you need flexible parsing of both single and mixed quantities, please use getQuantity() method of the Quantities facade instead.
csq - the decimal value and its unit (if any) separated by space(s).SimpleQuantityFormat.getInstance().parse(csq)protected boolean hasFraction(double value)
protected boolean hasFraction(BigDecimal value)
protected NumberSystem numberSystem()
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