org.unitConverter.unit

Class Unit

java.lang.Object

org.unitConverter.unit.Unit

Direct Known Subclasses:

BaseUnit, LinearUnit

public abstract class Unit
extends java.lang.Object

A unit that is composed of base units.

Since:

2019-10-16

Author:

Adrien Hopkins

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Unit(ObjectProduct<BaseUnit> unitBase, NameSymbol ns) Creates the AbstractUnit.

Method Summary

Modifier and Type	Method and Description
boolean	canConvertTo(Unit other) Checks if a value expressed in this unit can be converted to a value expressed in other
protected abstract double	convertFromBase(double value) Converts from a value expressed in this unit's base unit to a value expressed in this unit.
double	convertTo(Unit other, double value) Converts a value expressed in this unit to a value expressed in other.
protected abstract double	convertToBase(double value) Converts from a value expressed in this unit to a value expressed in this unit's base unit.
static Unit	fromConversionFunctions(ObjectProduct<BaseUnit> base, java.util.function.DoubleUnaryOperator converterFrom, java.util.function.DoubleUnaryOperator converterTo) Returns a unit from its base and the functions it uses to convert to and from its base.
static Unit	fromConversionFunctions(ObjectProduct<BaseUnit> base, java.util.function.DoubleUnaryOperator converterFrom, java.util.function.DoubleUnaryOperator converterTo, NameSymbol ns) Returns a unit from its base and the functions it uses to convert to and from its base.
ObjectProduct<BaseUnit>	getBase()
ObjectProduct<BaseDimension>	getDimension()
java.util.Set<java.lang.String>	getOtherNames()
java.util.Optional<java.lang.String>	getPrimaryName()
java.util.Optional<java.lang.String>	getSymbol()
java.lang.String	toString()
Unit	withName(NameSymbol ns)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Unit

protected Unit(ObjectProduct<BaseUnit> unitBase,
               NameSymbol ns)

Creates the AbstractUnit.

Parameters:

unitBase - base of unit

ns - names and symbol of unit

Throws:

java.lang.NullPointerException - if unitBase or ns is null

Since:

2019-10-16

Method Detail

fromConversionFunctions

public static final Unit fromConversionFunctions(ObjectProduct<BaseUnit> base,
                                                 java.util.function.DoubleUnaryOperator converterFrom,
                                                 java.util.function.DoubleUnaryOperator converterTo)

Returns a unit from its base and the functions it uses to convert to and from its base.

For example, to get a unit representing the degree Celsius, the following code can be used: Unit.fromConversionFunctions(SI.KELVIN, tempK -> tempK - 273.15, tempC -> tempC + 273.15);

Parameters:

base - unit's base

converterFrom - function that accepts a value expressed in the unit's base and returns that value expressed in this unit.

converterTo - function that accepts a value expressed in the unit and returns that value expressed in the unit's base.

Returns:

a unit that uses the provided functions to convert.

Throws:

java.lang.NullPointerException - if any argument is null

Since:

2019-05-22

fromConversionFunctions

public static final Unit fromConversionFunctions(ObjectProduct<BaseUnit> base,
                                                 java.util.function.DoubleUnaryOperator converterFrom,
                                                 java.util.function.DoubleUnaryOperator converterTo,
                                                 NameSymbol ns)

Returns a unit from its base and the functions it uses to convert to and from its base.

For example, to get a unit representing the degree Celsius, the following code can be used: Unit.fromConversionFunctions(SI.KELVIN, tempK -> tempK - 273.15, tempC -> tempC + 273.15);

Parameters:

base - unit's base

converterFrom - function that accepts a value expressed in the unit's base and returns that value expressed in this unit.

converterTo - function that accepts a value expressed in the unit and returns that value expressed in the unit's base.

ns - names and symbol of unit

Returns:

a unit that uses the provided functions to convert.

Throws:

java.lang.NullPointerException - if any argument is null

Since:

2019-05-22

canConvertTo

public final boolean canConvertTo(Unit other)

Checks if a value expressed in this unit can be converted to a value expressed in other

Parameters:

other - unit to test with

Returns:

true if the units are compatible

Throws:

java.lang.NullPointerException - if other is null

Since:

2019-01-13, v0.1.0

convertFromBase

protected abstract double convertFromBase(double value)

Converts from a value expressed in this unit's base unit to a value expressed in this unit.

This must be the inverse of convertToBase, so convertFromBase(convertToBase(value)) must be equal to value for any value, ignoring precision loss by roundoff error.

If this unit is a base unit, this method should return value.

Parameters:

value - value expressed in base unit

Returns:

value expressed in this unit

Since:

2018-12-22, v0.1.0

Implementation Requirements:

This method is used by convertTo(org.unitConverter.unit.Unit, double), and its behaviour affects the behaviour of convertTo.

convertTo

public final double convertTo(Unit other,
                              double value)

Converts a value expressed in this unit to a value expressed in other.

Parameters:

other - unit to convert to

value - value to convert

Returns:

converted value

Throws:

java.lang.IllegalArgumentException - if other is incompatible for conversion with this unit (as tested by canConvertTo(org.unitConverter.unit.Unit)).

java.lang.NullPointerException - if other is null

Since:

2019-05-22

Implementation Requirements:

If unit conversion is possible, this implementation returns other.convertFromBase(this.convertToBase(value)). Therefore, overriding either of those methods will change the output of this method.

convertToBase

protected abstract double convertToBase(double value)

Converts from a value expressed in this unit to a value expressed in this unit's base unit.

This must be the inverse of convertFromBase, so convertToBase(convertFromBase(value)) must be equal to value for any value, ignoring precision loss by roundoff error.

If this unit is a base unit, this method should return value.

Parameters:

value - value expressed in this unit

Returns:

value expressed in base unit

Since:

2018-12-22, v0.1.0

Implementation Requirements:

This method is used by convertTo(org.unitConverter.unit.Unit, double), and its behaviour affects the behaviour of convertTo.

getBase

public final ObjectProduct<BaseUnit> getBase()

Returns:

combination of units that this unit is based on

Since:

2018-12-22, v0.1.0

getDimension

public final ObjectProduct<BaseDimension> getDimension()

Returns:

dimension measured by this unit

Since:

2018-12-22, v0.1.0

getOtherNames

public final java.util.Set<java.lang.String> getOtherNames()

Returns:

additionalNames

Since:

2019-10-21

getPrimaryName

public final java.util.Optional<java.lang.String> getPrimaryName()

Returns:

primaryName

Since:

2019-10-21

getSymbol

public final java.util.Optional<java.lang.String> getSymbol()

Returns:

symbol

Since:

2019-10-21

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

withName

public Unit withName(NameSymbol ns)

Parameters:

ns - name(s) and symbol to use

Returns:

a copy of this unit with provided name(s) and symbol

Throws:

java.lang.NullPointerException - if ns is null

Since:

2019-10-21