AbstractQuantity (Units of Measurement Reference Implementation 2.0.2 API)

java.lang.Object
- tech.units.indriya.AbstractQuantity<Q>

All Implemented Interfaces:

Serializable, Comparable<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:

1.11, Jun 9, 2019

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

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
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 tech.units.indriya.ComparableQuantity
add, divide, divide, inverse, multiply, multiply, subtract

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

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.
  - isEquivalentTo
```
public boolean isEquivalentTo(javax.measure.Quantity<Q> that)
```
    Description copied from interface: ComparableQuantity
    
    Compares two instances of Quantity <Q>, doing the conversion of unit if necessary.
    
    Specified by:
    
    isEquivalentTo 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.
    
    See Also:
    
    Cambridge Dictionary: equivalent, LEXICO: equivalent
  - 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.
    Quatity 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)
```
  - hasFraction
```
protected boolean hasFraction(BigDecimal value)
```
  - numberSystem
```
protected NumberSystem numberSystem()
```

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

Nested Class Summary

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

Field Summary

Constructor Summary

Method Summary

Methods inherited from interface tech.units.indriya.ComparableQuantity

Methods inherited from class java.lang.Object

Methods inherited from interface javax.measure.Quantity

Field Detail

NONE

ONE

Constructor Detail

AbstractQuantity

AbstractQuantity

Method Detail

getValue

getUnit

getScale

to

isGreaterThan

isGreaterThanOrEqualTo

isLessThan

isLessThanOrEqualTo

isEquivalentTo

compareTo

equals

hashCode

toString

divide

multiply

inverse

asType

parse

hasFraction

hasFraction

numberSystem