org.apache.sis.measure

Class UnitServices

Object

ServiceProvider

UnitServices

All Implemented Interfaces:

SystemOfUnitsService, UnitFormatService

public class UnitServices
extends ServiceProvider
implements SystemOfUnitsService, UnitFormatService

The central point from which all unit services (parsing, formatting, listing, etc) can be obtained. Apache SIS does not use this class (SIS rather uses Units pre-defined constants and Unit­Format directly since they are designed specifically for SIS needs). This class is provided for allowing other applications to discover Apache SIS implementation of JSR-363 without direct dependency. A Unit­Services instance can be obtained by call to Service­Provider.current().

Since:

0.8

Defined in the sis-utility module

Constructor Summary

Constructors

Constructor and Description
UnitServices() Creates a new service provider.

Method Summary

Modifier and Type	Method and Description
Set<String>	getAvailableFormatNames() Returns a list of available format names.
Collection<SystemOfUnits>	getAvailableSystemsOfUnits() Returns the list of all available systems of units.
<Q extends Quantity<Q>> QuantityFactory<Q>	getQuantityFactory(Class<Q> type) Return a factory for the given Quantity type.
SystemOfUnits	getSystemOfUnits() Returns the default system of units used by Apache SIS.
SystemOfUnits	getSystemOfUnits(String name) Returns the system of units having the specified name, or null if none.
SystemOfUnitsService	getSystemOfUnitsService() Returns the service to obtain a System­Of­Units instances.
UnitFormat	getUnitFormat() Returns an unit format instance for human-readable unit symbols in the default locale.
UnitFormat	getUnitFormat(String name) Returns the unit format for the given name.
UnitFormatService	getUnitFormatService() Returns the service to obtain a Unit­Format instances.

Methods inherited from class ServiceProvider

available, current, get­Priority, set­Current

Methods inherited from class Object

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

Constructor Detail

UnitServices

public UnitServices()

Creates a new service provider. Unit­Services should not be instantiated directly unless the caller wants specifically the Apache SIS implementation. For obtaining the default implementation, use Service­Provider.current() instead.

Method Detail

getSystemOfUnits

public SystemOfUnits getSystemOfUnits()

Returns the default system of units used by Apache SIS. This include the International System of Units (SI) together with some imperial units and other units. This system includes at least all the constants defined in the Units class.

Specified by:

get­System­Of­Units in interface System­Of­Units­Service

Returns:

the system of units used by Apache SIS.

getSystemOfUnits

public SystemOfUnits getSystemOfUnits(String name)

Returns the system of units having the specified name, or null if none. The argument can be any name in the following table:

Available system of units

Name	Examples
SI	m, km, m³, s, m∕s, K, °C, hPa, rad, µrad
SI + accepted	s, min, h, m∕s, km∕h, °, ′, ″, ha
Imperial	in, ft, mi (statute mile)
SI + other	m, m∕s, km∕h, ft, mi, M (nautical mile)

The search for name is case-insensitive and ignore whitespaces.

Specified by:

get­System­Of­Units in interface System­Of­Units­Service

Parameters:

name - the name of the desired system of units.

Returns:

the system of units for the given name, or null if none.

getAvailableSystemsOfUnits

public Collection<SystemOfUnits> getAvailableSystemsOfUnits()

Returns the list of all available systems of units.

Specified by:

get­Available­Systems­Of­Units in interface System­Of­Units­Service

Returns:

list of available systems of units.

getSystemOfUnitsService

public SystemOfUnitsService getSystemOfUnitsService()

Returns the service to obtain a System­Of­Units instances. The default implementation returns this since this Unit­Services class implements directly all relevant interfaces. The methods related to system of units are:

• get­System­Of­Units()
• get­System­Of­Units(String)
• get­Available­Systems­Of­Units()

Specified by:

get­System­Of­Units­Service in class Service­Provider

Returns:

the service to obtain a System­Of­Units, or null if none.

getUnitFormat

public UnitFormat getUnitFormat()

Returns an unit format instance for human-readable unit symbols in the default locale. The format style is Unit­Format.Style.SYMBOL. This style requires support for Unicode characters; for example square metres are formatted as “m²”, not “m2”.

Specified by:

get­Unit­Format in interface Unit­Format­Service

Returns:

a Unit­Format instance for unit symbols.

getUnitFormat

public UnitFormat getUnitFormat(String name)

Returns the unit format for the given name. The argument can be the name of any value in the Unit­Format.Style enumeration. The argument can be any name in the following table:

Available unit format name

Name	Examples
SYMBOL	km, m³, m∕s, N⋅m, K, °C, hPa, rad, µrad
UCUM	km, m3, m/s, N.m
NAME	kilometre, cubic metre, metres per second

The "NAME" format is locale-sensitive. The format locale can be modified by a call to Unit­Format.set­Locale(Locale) on the returned object.

Specified by:

get­Unit­Format in interface Unit­Format­Service

Parameters:

name - the name of the desired format.

Returns:

the corresponding unit format, or null if none.

getAvailableFormatNames

public Set<String> getAvailableFormatNames()

Returns a list of available format names. The default implementation returns the names of all values in the Unit­Format.Style enumeration.

Specified by:

get­Available­Format­Names in interface Unit­Format­Service

Returns:

list of available formats.

getUnitFormatService

public UnitFormatService getUnitFormatService()

Returns the service to obtain a Unit­Format instances. The default implementation returns this since this Unit­Services class implements directly all relevant interfaces. The methods related to unit formats are:

• get­Unit­Format()
• get­Unit­Format(String)
• get­Available­Format­Names()

Specified by:

get­Unit­Format­Service in class Service­Provider

Returns:

the service to obtain a Unit­Format, or null if none.

getQuantityFactory

public <Q extends Quantity<Q>> QuantityFactory<Q> getQuantityFactory(Class<Q> type)

Return a factory for the given Quantity type. In the particular case of Apache SIS implementation, Quantities.create(double, Unit) provides a more direct way to instantiate quantities.

Specified by:

get­Quantity­Factory in class Service­Provider

Type Parameters:

Q - compile-time value of the type argument.

Parameters:

type - type of the desired the quantity.

Returns:

the service to obtain Quantity instances, or null if none.

See Also:

Quantities.create(double, Unit)