Package tech.units.indriya.function

Class AbstractConverter

java.lang.Object

tech.units.indriya.function.AbstractConverter

All Implemented Interfaces:

Serializable, Comparable<javax.measure.UnitConverter>, javax.measure.UnitConverter, tech.uom.lib.common.function.Converter<Number,Number>

Direct Known Subclasses:

AbstractConverter.Pair, AddConverter, ExpConverter, LogConverter, PowerOfIntConverter, RationalConverter

public abstract class AbstractConverter
extends Object
implements javax.measure.UnitConverter, tech.uom.lib.common.function.Converter<Number,Number>, Serializable, Comparable<javax.measure.UnitConverter>

The base class for our UnitConverter implementations.

Since:

1.0

Version:

2.1, Mai 28, 2020

Author:

Jean-Marie Dautelle, Werner Keil, Andi Huber

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AbstractConverter.Pair	This class represents converters made up of two or more separate converters (in matrix notation [pair] = [left] x [right]).

Field Summary

Fields

Modifier and Type	Field	Description
protected List<? extends javax.measure.UnitConverter>	conversionSteps	memorization for getConversionSteps
static AbstractConverter	IDENTITY	Default identity converter implementing AbstractConverter.
static ConverterCompositionHandler	UNIT_COMPOSITION_HANDLER	Allows for plug in of a custom UnitCompositionHandler.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractConverter()	DefaultQuantityFactory constructor.

Method Summary

Modifier and Type	Method	Description
protected abstract boolean	canReduceWith(AbstractConverter that)	Non-API Guard for reduce(AbstractConverter)
javax.measure.UnitConverter	concatenate(javax.measure.UnitConverter converter)
double	convert(double value)
Number	convert(Number value)
protected abstract Number	convertWhenNotIdentity(Number value)	Non-API
abstract boolean	equals(Object cvtr)
List<? extends javax.measure.UnitConverter>	getConversionSteps()
abstract int	hashCode()
AbstractConverter	inverse()
protected abstract AbstractConverter	inverseWhenNotIdentity()	Non-API
Optional<Number>	linearFactor()	Even though transformations may be composed of addition and multiplication, the first derivative might just be a linear function.
protected AbstractConverter	reduce(AbstractConverter that)	Non-API Guarded by canReduceWith(AbstractConverter)
String	toString()
protected abstract String	transformationLiteral()	Non-API

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Comparable

compareTo

Methods inherited from interface javax.measure.UnitConverter

isIdentity, isLinear

Field Detail

IDENTITY

public static final AbstractConverter IDENTITY

Default identity converter implementing AbstractConverter.

Note: Checking whether a UnitConverter is an identity operator should be done with UnitConverter.isIdentity() rather than checking for object identity unitConverter == AbstractConverter.IDENTITY.

UNIT_COMPOSITION_HANDLER

public static ConverterCompositionHandler UNIT_COMPOSITION_HANDLER

Allows for plug in of a custom UnitCompositionHandler.

conversionSteps

protected List<? extends javax.measure.UnitConverter> conversionSteps

memorization for getConversionSteps

Constructor Detail

AbstractConverter

protected AbstractConverter()

DefaultQuantityFactory constructor.

Method Detail

equals

public abstract boolean equals(Object cvtr)

Overrides:

equals in class Object

hashCode

public abstract int hashCode()

Overrides:

hashCode in class Object

transformationLiteral

protected abstract String transformationLiteral()

Non-API

Returns a String describing the transformation that is represented by this converter. Contributes to converter's toString method. If null or empty toString output becomes simplified.

Returns:

toString

public final String toString()

Overrides:

toString in class Object

inverseWhenNotIdentity

protected abstract AbstractConverter inverseWhenNotIdentity()

Non-API

Returns an AbstractConverter that represents the inverse transformation of this converter, for cases where the transformation is not the identity transformation.

Returns:

inverse

public final AbstractConverter inverse()

Specified by:

inverse in interface javax.measure.UnitConverter

canReduceWith

protected abstract boolean canReduceWith(AbstractConverter that)

Non-API Guard for reduce(AbstractConverter)

Parameters:

that -

Returns:

whether or not a composition with given that is possible, such that no additional conversion steps are required, with respect to the steps already in place by this converter

reduce

protected AbstractConverter reduce(AbstractConverter that)

Non-API Guarded by canReduceWith(AbstractConverter)

Parameters:

that -

Returns:

a new AbstractConverter that adds no additional conversion steps, with respect to the steps already in place by this converter

concatenate

public final javax.measure.UnitConverter concatenate(javax.measure.UnitConverter converter)

Specified by:

concatenate in interface javax.measure.UnitConverter

getConversionSteps

public final List<? extends javax.measure.UnitConverter> getConversionSteps()

Specified by:

getConversionSteps in interface javax.measure.UnitConverter

convertWhenNotIdentity

protected abstract Number convertWhenNotIdentity(Number value)

Non-API

Parameters:

value -

Returns:

transformed value

convert

public final double convert(double value)

Specified by:

convert in interface javax.measure.UnitConverter

convert

public final Number convert(Number value)

Specified by:

convert in interface tech.uom.lib.common.function.Converter<Number,Number>

Specified by:

convert in interface javax.measure.UnitConverter

Throws:

IllegalArgumentException - if the value is null.

linearFactor

public Optional<Number> linearFactor()

Even though transformations may be composed of addition and multiplication, the first derivative might just be a linear function. This is strictly required for Quantities that are expressed with RELATIVE scope. Eg. Δ2°C or Δ2°F. Otherwise such deltas cannot be converted to ABSOLUTE scope without additional information.

Returns:

optionally the linear factor of this transformation's first derivative, based on whether this transformation allows for RELATIVE scaled Quantities