ome.units.unit

Class Unit<Q extends Quantity>

java.lang.Object

ome.units.unit.Unit<Q>

public class Unit<Q extends Quantity>
extends Object

Unit of measurement. The representation of a unit of measurement. This generic type is specialised by the dimension type for the unit; for example Length. A unit of measurement belongs to a measurement system with a corresponding symbol. Additionally, a scaling factor and offset provide the means to scale the unit to the base unit for the measuring system, and hence perform unit conversions. There is always one measurement system per dimension type, but additional systems may be added, and these may or may not be interconvertible. For example, an abstract length representation such as pixel size would not be convertible to the SI length units without an explicit conversion with a conversion factor.

Since:

5.1.0

Field Summary

Fields

Modifier and Type	Field and Description
private String	measurementSystem The measurement system for the dimension type
private Double	offset The conversion offset for this unit.
private Double	scaleFactor The conversion scaling factor for this unit.
private String	symbol The symbol for this unit.

Constructor Summary

Constructors

Modifier	Constructor and Description
private	Unit(String inSystem, String inSymbol, Double inScaleFactor, Double inOffset) Create a unit.

Method Summary

Methods

Modifier and Type	Method and Description
Unit<Q>	add(Double scalar) Increase the scaling offset in this unit by a scalar.
Unit<Q>	add(Integer scalar) Increase the scaling offset in this unit by a scalar.
Double	convertValue(Number inValue, Unit<Q> inUnit) Convert a value in this unit to the specified unit.
static <Q extends Quantity> Unit<Q>	CreateBaseUnit(String inMeasurementSystem, String inSymbol) Create the "base unit" for a given measurement system.
Unit<Q>	divide(Double scalar) Divide the scaling conversion factor in this unit by a scalar.
Unit<Q>	divide(Integer scalar) Divide the scaling conversion factor in this unit by a scalar.
Double	getOffset() Get the conversion offset for this unit.
Double	getScaleFactor() Get the conversion scaling factor for this unit.
String	getSymbol() Get the symbol for this unit.
Boolean	isConvertible(Unit<Q> inUnit) Check if this unit is convertible to another unit.
Unit<Q>	multiply(Double scalar) Multiply the scaling conversion factor in this unit by a scalar.
Unit<Q>	multiply(Integer scalar) Multiply the scaling conversion factor in this unit by a scalar.
Unit<Q>	prefixSymbol(String prefix) Add a prefix to the unit symbol in this unit.
Unit<Q>	setSymbol(String inSymbol) Change the unit symbol in this unit.

Methods inherited from class java.lang.Object

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

Field Detail

measurementSystem

private final String measurementSystem

The measurement system for the dimension type

symbol

private final String symbol

The symbol for this unit.

scaleFactor

private final Double scaleFactor

The conversion scaling factor for this unit.

offset

private final Double offset

The conversion offset for this unit.

Constructor Detail

Unit

private Unit(String inSystem,
    String inSymbol,
    Double inScaleFactor,
    Double inOffset)

Create a unit.

Parameters:

inSystem - the measurement system.

inSymbol - the unit symbol.

inScaleFactor - the conversion scaling factor (1.0 for base unit).

inOffset - the conversion offset (0.0 for base unit).

Method Detail

getSymbol

public String getSymbol()

Get the symbol for this unit.

Returns:

the symbol.

getScaleFactor

public Double getScaleFactor()

Get the conversion scaling factor for this unit.

Returns:

the scaling factor.

getOffset

public Double getOffset()

Get the conversion offset for this unit.

Returns:

the offset.

isConvertible

public Boolean isConvertible(Unit<Q> inUnit)

Check if this unit is convertible to another unit.

Parameters:

inUnit - the unit to which to convert.

Returns:

true if convertible or false if not convertible.

convertValue

public Double convertValue(Number inValue,
                  Unit<Q> inUnit)

Convert a value in this unit to the specified unit.

Parameters:

inValue - the value to convert.

inUnit - the unit to which to convert.

Returns:

the converted value

Throws:

ArithmeticException - if the conversion is not possible.

multiply

public Unit<Q> multiply(Integer scalar)

Multiply the scaling conversion factor in this unit by a scalar.

Parameters:

scalar - the multiplication factor.

Returns:

a new Unit containing the result of the multiplication.

multiply

public Unit<Q> multiply(Double scalar)

Multiply the scaling conversion factor in this unit by a scalar.

Parameters:

scalar - the multiplication factor.

Returns:

a new Unit with the result of the multiplication.

divide

public Unit<Q> divide(Integer scalar)

Divide the scaling conversion factor in this unit by a scalar.

Parameters:

scalar - the division factor.

Returns:

a new Unit with the result of the division.

divide

public Unit<Q> divide(Double scalar)

Divide the scaling conversion factor in this unit by a scalar.

Parameters:

scalar - the division factor.

Returns:

a new Unit with the result of the division.

add

public Unit<Q> add(Integer scalar)

Increase the scaling offset in this unit by a scalar.

Parameters:

scalar - the value to add.

Returns:

a new Unit with the result of the addition.

add

public Unit<Q> add(Double scalar)

Increase the scaling offset in this unit by a scalar.

Parameters:

scalar - the value to add.

Returns:

a new Unit with the result of the addition.

setSymbol

public Unit<Q> setSymbol(String inSymbol)

Change the unit symbol in this unit.

Parameters:

inSymbol - the new unit symbol.

Returns:

a new Unit with the result of the unit symbol change.

prefixSymbol

public Unit<Q> prefixSymbol(String prefix)

Add a prefix to the unit symbol in this unit.

Parameters:

prefix - the unit symbol prefix.

Returns:

a new Unit with the result of the unit symbol prefix addition.

CreateBaseUnit

public static <Q extends Quantity> Unit<Q> CreateBaseUnit(String inMeasurementSystem,
                                          String inSymbol)

Create the "base unit" for a given measurement system. This is the default or reference unit representing unity for the measurement system. For example, for a unit system representing length, the measurement system and symbol could be "SI.METRE" and "m", respectively.

Parameters:

inMeasurementSystem - the name of the measurement system.

inSymbol - the symbol of the base unit.