Top Description Fields Constructors Methods
tech.units.indriya.unit

public final Class AlternateUnit<Q extends Quantity<Q>>

extends AbstractUnit<Q extends Quantity<Q>>
Class Inheritance
Imports
javax.measure.Dimension, .Quantity, .Unit, .UnitConverter, tech.units.indriya.AbstractUnit, java.util.Map, .Objects

This class represents units used in expressions to distinguish between quantities of a different nature but of the same dimensions.

Examples of alternate units:

Unit<Angle> RADIAN = AlternateUnit.of(ONE, "rad").asType(Angle.class);
Unit<Force> NEWTON = AlternateUnit.of(METRE.multiply(KILOGRAM).divide(SECOND.pow(2)), "N").asType(Force.class);
Unit<Pressure> PASCAL = AlternateUnit.of(NEWTON.divide(METRE.pow(2), "Pa").asType(Pressure.class);
Authors
Jean-Marie Dautelle, Werner Keil
Since
1.0
Version
2.1, October 3, 2024

Field Summary

Modifier and TypeField and Description
private final Unit<?>
parentUnit

Holds the parent unit (a system unit).

private static final long
serialVersionUID

Hides tech.units.indriya.AbstractUnit.serialVersionUID.

Inherited from tech.units.indriya.AbstractUnit:
ONEscaleSYMBOL_TO_UNIT

Constructor Summary

AccessConstructor and Description
public
AlternateUnit(Unit<?>
the system unit from which this alternate unit is derived.
parentUnit, String
the symbol for this alternate unit.
symbol)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

pack-priv
AlternateUnit(Unit<?>
the system unit from which this alternate unit is derived.
parentUnit, String
the symbol for this alternate unit.
symbol, String
the name for this alternate unit.
name)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

Method Summary

Modifier and TypeMethod and Description
public boolean
equals(Object
the reference object with which to compare.
obj)

Implements abstract tech.units.indriya.AbstractUnit.equals.

Indicates whether some other object is "equal to" this one.

public Map<? extends Unit<?>, Integer>
getBaseUnits()

Implements abstract tech.units.indriya.AbstractUnit.getBaseUnits.

Implements javax.measure.Unit.getBaseUnits.

Returns the base units and their exponent whose product is this unit, or null if this unit is a base unit (not a product of existing units).

public Dimension
getDimension()

Implements abstract tech.units.indriya.AbstractUnit.getDimension.

Implements javax.measure.Unit.getDimension.

Returns the dimension of this unit.

public Unit<?>

Returns:

the parent unit.
getParentUnit()

Returns the parent unit of this alternate unit, always a system unit and never an alternate unit.

public UnitConverter
getSystemConverter()

Implements abstract tech.units.indriya.AbstractUnit.getSystemConverter.

Returns the converter from this unit to its unscaled System Unit unit.

public int
hashCode()

Implements abstract tech.units.indriya.AbstractUnit.hashCode.

Returns a hash code value for this object.

public static <Q extends Quantity<Q>> AlternateUnit<Q>
of(Unit<?>
the system unit from which this alternate unit is derived.
parent, String
the symbol for this alternate unit.
symbol)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

public static <Q extends Quantity<Q>> AlternateUnit<Q>
of(Unit<?>
the system unit from which this alternate unit is derived.
parent, String
the symbol for this alternate unit.
symbol, String
the name for this alternate unit.
name)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

public Unit<Q>
toSystemUnit()

Implements abstract tech.units.indriya.AbstractUnit.toSystemUnit.

Returns the unscaled SI unit from which this unit is derived.

Inherited from tech.units.indriya.AbstractUnit:
alternateannotateasTypecompareTodividedividedividegetActualTypegetConverterTogetConverterTogetConverterToAnygetConverterToAnygetNamegetSymbolgetSystemUnitinternalGetConverterToinverseisCompatibleisEquivalentToisSystemUnitmultiplymultiplymultiplyparsepowprefixrootsetNamesetSymbolshiftshifttoStringtransform

Field Detail

parentUnitback to summary
private final Unit<?> parentUnit

Holds the parent unit (a system unit).

serialVersionUIDback to summary
private static final long serialVersionUID

Hides tech.units.indriya.AbstractUnit.serialVersionUID.

Constructor Detail

AlternateUnitback to summary
public AlternateUnit(Unit<?> parentUnit, String symbol)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

Parameters
parentUnit:Unit<?>

the system unit from which this alternate unit is derived.

symbol:String

the symbol for this alternate unit.

Annotations
@SuppressWarnings:rawtypes
Exceptions
IllegalArgumentException:
if the specified parent unit is not an system unit
AlternateUnitback to summary
pack-priv AlternateUnit(Unit<?> parentUnit, String symbol, String name)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

Parameters
parentUnit:Unit<?>

the system unit from which this alternate unit is derived.

symbol:String

the symbol for this alternate unit.

name:String

the name for this alternate unit.

Exceptions
IllegalArgumentException:
if the specified parent unit is not an system unit
Since
2.0

Method Detail

equalsback to summary
public boolean equals(Object obj)

Implements abstract tech.units.indriya.AbstractUnit.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

  • It is reflexive: for any non-null reference value x, x.equals(x) should return true.
  • It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
  • It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
  • It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
  • For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
obj:Object

the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

Annotations
@SuppressWarnings:rawtypes
@Override
getBaseUnitsback to summary
public Map<? extends Unit<?>, Integer> getBaseUnits()

Implements abstract tech.units.indriya.AbstractUnit.getBaseUnits.

Implements javax.measure.Unit.getBaseUnits.

Doc from javax.measure.Unit.getBaseUnits.

Returns the base units and their exponent whose product is this unit, or null if this unit is a base unit (not a product of existing units).

Returns:Map<? extends Unit<?>, Integer>

the base units and their exponent making up this unit.

Annotations
@Override
getDimensionback to summary
public Dimension getDimension()

Implements abstract tech.units.indriya.AbstractUnit.getDimension.

Implements javax.measure.Unit.getDimension.

Doc from javax.measure.Unit.getDimension.

Returns the dimension of this unit. Two units u1 and u2 are compatible if and only if u1.getDimension().equals(u2.getDimension()).

Returns:Dimension

the dimension of this unit.

Annotations
@Override
getParentUnitback to summary
public Unit<?> getParentUnit()

Returns the parent unit of this alternate unit, always a system unit and never an alternate unit.

Returns:Unit<?>

the parent unit.

getSystemConverterback to summary
public UnitConverter getSystemConverter()

Implements abstract tech.units.indriya.AbstractUnit.getSystemConverter.

Doc from tech.units.indriya.AbstractUnit.getSystemConverter.

Returns the converter from this unit to its unscaled System Unit unit.

Returns:UnitConverter

getConverterTo(this.toSystemUnit())

Annotations
@SuppressWarnings:rawtypes
@Override
hashCodeback to summary
public int hashCode()

Implements abstract tech.units.indriya.AbstractUnit.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for this object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

  • Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
  • If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
  • It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns:int

a hash code value for this object

Annotations
@Override
ofback to summary
public static <Q extends Quantity<Q>> AlternateUnit<Q> of(Unit<?> parent, String symbol)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

Parameters
parent:Unit<?>

the system unit from which this alternate unit is derived.

symbol:String

the symbol for this alternate unit.

Exceptions
IllegalArgumentException:
if the specified parent unit is not an unscaled standard system unit.
MeasurementException:
if the specified symbol is not valid or is already associated to a different unit.
ofback to summary
public static <Q extends Quantity<Q>> AlternateUnit<Q> of(Unit<?> parent, String symbol, String name)

Creates an alternate unit for the specified system unit identified by the specified name and symbol.

Parameters
parent:Unit<?>

the system unit from which this alternate unit is derived.

symbol:String

the symbol for this alternate unit.

name:String

the name for this alternate unit.

Exceptions
IllegalArgumentException:
if the specified parent unit is not an unscaled standard system unit.
MeasurementException:
if the specified symbol is not valid or is already associated to a different unit.
Since
2.0
toSystemUnitback to summary
public Unit<Q> toSystemUnit()

Implements abstract tech.units.indriya.AbstractUnit.toSystemUnit.

Doc from tech.units.indriya.AbstractUnit.toSystemUnit.

Returns the unscaled SI unit from which this unit is derived. The SI unit can be be used to identify a quantity given the unit. For example: static boolean isAngularVelocity(AbstractUnit unit) { return unit.toSystemUnit().equals(RADIAN.divide(SECOND)); } assert(REVOLUTION.divide(MINUTE).isAngularVelocity()); // Returns true.

Returns:Unit<Q>

the unscaled metric unit from which this unit is derived.

Annotations
@Override