javax.measure.unit

Class UnitFormat

java.lang.Object

java.text.Format

javax.measure.unit.UnitFormat

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public abstract class UnitFormat
extends java.text.Format

This class provides the interface for formatting and parsing units.

For all SI units, the 20 SI prefixes used to form decimal multiples and sub-multiples of SI units are recognized. NonSI units are directly recognized. For example:

        Unit.valueOf("m°C").equals(SI.MILLI(SI.CELSIUS))
        Unit.valueOf("kW").equals(SI.KILO(SI.WATT))
        Unit.valueOf("ft").equals(SI.METER.multiply(0.3048))

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class java.text.Format

java.text.Format.Field

Method Summary

Modifier and Type	Method and Description
abstract void	alias(Unit<?> unit, java.lang.String alias) Attaches a system-wide alias to this unit.
java.lang.StringBuffer	format(java.lang.Object unit, java.lang.StringBuffer toAppendTo, java.text.FieldPosition pos) Formats an unit and appends the resulting text to a given string buffer (implements java.text.Format).
abstract java.lang.Appendable	format(Unit<?> unit, java.lang.Appendable appendable) Formats the specified unit.
static UnitFormat	getInstance() Returns the unit format for the default locale (format used by Unit.valueOf(CharSequence) and Unit.toString()).
static UnitFormat	getInstance(java.util.Locale inLocale) Returns the unit format for the specified locale.
static UnitFormat	getUCUMInstance() Returns the UCUM international unit format; this format uses characters range 0000-007F exclusively and is not locale-sensitive.
abstract boolean	isValidIdentifier(java.lang.String name) Indicates if the specified name can be used as unit identifier.
abstract void	label(Unit<?> unit, java.lang.String label) Attaches a system-wide label to the specified unit.
Unit<?>	parseObject(java.lang.String source, java.text.ParsePosition pos) Parses the text from a string to produce an object (implements java.text.Format).
abstract Unit<? extends Quantity>	parseProductUnit(java.lang.CharSequence csq, java.text.ParsePosition pos) Parses a sequence of character to produce a unit or a rational product of unit.
abstract Unit<? extends Quantity>	parseSingleUnit(java.lang.CharSequence csq, java.text.ParsePosition pos) Parses a sequence of character to produce a single unit.

Methods inherited from class java.text.Format

clone, format, formatToCharacterIterator, parseObject

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static UnitFormat getInstance()

Returns the unit format for the default locale (format used by Unit.valueOf(CharSequence) and Unit.toString()).

Returns:

the default unit format (locale sensitive).

getInstance

public static UnitFormat getInstance(java.util.Locale inLocale)

Returns the unit format for the specified locale.

Returns:

the unit format for the specified locale.

getUCUMInstance

public static UnitFormat getUCUMInstance()

Returns the UCUM international unit format; this format uses characters range 0000-007F exclusively and is not locale-sensitive. For example: kg.m/s2

Returns:

the UCUM international format.

format

public abstract java.lang.Appendable format(Unit<?> unit,
                                            java.lang.Appendable appendable)
                                     throws java.io.IOException

Formats the specified unit.

Parameters:

unit - the unit to format.

appendable - the appendable destination.

Throws:

java.io.IOException - if an error occurs.

parseProductUnit

public abstract Unit<? extends Quantity> parseProductUnit(java.lang.CharSequence csq,
                                                          java.text.ParsePosition pos)
                                                   throws java.text.ParseException

Parses a sequence of character to produce a unit or a rational product of unit.

Parameters:

csq - the CharSequence to parse.

pos - an object holding the parsing index and error position.

Returns:

an Unit parsed from the character sequence.

Throws:

java.lang.IllegalArgumentException - if the character sequence contains an illegal syntax.

java.text.ParseException

parseSingleUnit

public abstract Unit<? extends Quantity> parseSingleUnit(java.lang.CharSequence csq,
                                                         java.text.ParsePosition pos)
                                                  throws java.text.ParseException

Parses a sequence of character to produce a single unit.

Parameters:

csq - the CharSequence to parse.

pos - an object holding the parsing index and error position.

Returns:

an Unit parsed from the character sequence.

Throws:

java.lang.IllegalArgumentException - if the character sequence does not contain a valid unit identifier.

java.text.ParseException

label

public abstract void label(Unit<?> unit,
                           java.lang.String label)

Attaches a system-wide label to the specified unit. For example:

     UnitFormat.getInstance().label(DAY.multiply(365), "year");
     UnitFormat.getInstance().label(METER.multiply(0.3048), "ft");
 

If the specified label is already associated to an unit the previous association is discarded or ignored.

Parameters:

unit - the unit being labelled.

label - the new label for this unit.

Throws:

java.lang.IllegalArgumentException - if the label is not a isValidIdentifier(String) valid identifier.

alias

public abstract void alias(Unit<?> unit,
                           java.lang.String alias)

Attaches a system-wide alias to this unit. Multiple aliases may be attached to the same unit. Aliases are used during parsing to recognize different variants of the same unit. For example:

     UnitFormat.getLocaleInstance().alias(METER.multiply(0.3048), "foot");
     UnitFormat.getLocaleInstance().alias(METER.multiply(0.3048), "feet");
     UnitFormat.getLocaleInstance().alias(METER, "meter");
     UnitFormat.getLocaleInstance().alias(METER, "metre");
 

If the specified label is already associated to an unit the previous association is discarded or ignored.

Parameters:

unit - the unit being aliased.

alias - the alias attached to this unit.

Throws:

java.lang.IllegalArgumentException - if the label is not a isValidIdentifier(String) valid identifier.

isValidIdentifier

public abstract boolean isValidIdentifier(java.lang.String name)

Indicates if the specified name can be used as unit identifier.

Parameters:

name - the identifier to be tested.

Returns:

true if the name specified can be used as label or alias for this format;false otherwise.

format

public final java.lang.StringBuffer format(java.lang.Object unit,
                                           java.lang.StringBuffer toAppendTo,
                                           java.text.FieldPosition pos)

Formats an unit and appends the resulting text to a given string buffer (implements java.text.Format).

Specified by:

format in class java.text.Format

Parameters:

unit - the unit to format.

toAppendTo - where the text is to be appended

pos - the field position (not used).

Returns:

toAppendTo

parseObject

public final Unit<?> parseObject(java.lang.String source,
                                 java.text.ParsePosition pos)

Parses the text from a string to produce an object (implements java.text.Format).

Specified by:

parseObject in class java.text.Format

Parameters:

source - the string source, part of which should be parsed.

pos - the cursor position.

Returns:

the corresponding unit or null if the string cannot be parsed.