javax.measure.format

Interface UnitFormat

public interface UnitFormat

Formats instances of Unit to a String or Appendable and parses a CharSequence to a Unit.

Synchronization

Instances of this class are not required to be thread-safe. It is recommended to use separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

Since:

1.0

Version:

1.3, August 8, 2018

Author:

Jean-Marie Dautelle, Werner Keil

See Also:

Unit

Method Summary

Modifier and Type	Method and Description
java.lang.String	format(Unit<?> unit) Formats the specified Unit.
java.lang.Appendable	format(Unit<?> unit, java.lang.Appendable appendable) Formats the specified Unit.
default boolean	isLocaleSensitive() Returns true if this UnitFormat depends on a Locale to perform its tasks.
void	label(Unit<?> unit, java.lang.String label) Attaches a system-wide label to the specified unit.
Unit<?>	parse(java.lang.CharSequence csq) Parses the text into an instance of Unit.
Unit<?>	parse(java.lang.CharSequence csq, java.text.ParsePosition cursor) Parses a portion of the specified CharSequence from the specified position to produce a Unit.

Method Detail

format

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

Formats the specified Unit.

Parameters:

unit - the Unit to format, not null

appendable - the appendable destination.

Returns:

the appendable destination passed in with formatted text appended.

Throws:

java.io.IOException - if an error occurs while writing to the destination.

format

java.lang.String format(Unit<?> unit)

Formats the specified Unit.

Parameters:

unit - the Unit to format, not null

Returns:

the string representation using the settings of this UnitFormat.

label

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

Attaches a system-wide label to the specified unit.

If the specified label is already associated to a unit the previous association can be discarded or ignored. Depending on the UnitFormat implementation, this call may be ignored if the particular unit already has a label.

If a UnitFormat implementation is explicitly immutable, similar to e.g. the result of Collections.unmodifiableList(), then an UnsupportedOperationException may be thrown upon this call.

Since UnitFormat implementations often apply the Singleton pattern, system-wide means, the label applies to every instance of UnitFormatA implementing UnitFormat in this case, but not every instance of UnitFormatB or UnitFormatC both also implementing UnitFormat. If a UnitFormat #isLocaleSensitive() it is up to the implementation, whether the label is ignored, applied in a local-neutral manner (in addition to its local-sensitive information) or locale-specific.

Parameters:

unit - the unit being labeled.

label - the new label for this unit.

Throws:

java.lang.IllegalArgumentException - if the label is not a valid identifier. This may include characters not supported by a particular UnitFormat implementation (e.g. only ASCII characters for certain devices)

java.lang.UnsupportedOperationException - if the label operation is not supported by this UnitFormat

isLocaleSensitive

default boolean isLocaleSensitive()

Returns true if this UnitFormat depends on a Locale to perform its tasks.

In environments that do not support a Locale, e.g. Java ME, this usually returns false.

Returns:

Whether this format depends on the locale.

parse

Unit<?> parse(java.lang.CharSequence csq,
              java.text.ParsePosition cursor)
       throws java.lang.IllegalArgumentException,
              MeasurementParseException

Parses a portion of the specified CharSequence from the specified position to produce a Unit. If parsing succeeds, then the index of the cursor argument is updated to the index after the last character used.

Parameters:

csq - the CharSequence to parse.

cursor - the cursor holding the current parsing index.

Returns:

the unit parsed from the specified character sub-sequence.

Throws:

java.lang.IllegalArgumentException - if any problem occurs while parsing the specified character sequence (e.g. illegal syntax).

MeasurementParseException

parse

Unit<?> parse(java.lang.CharSequence csq)
       throws MeasurementParseException

Parses the text into an instance of Unit.

The parse must complete normally and parse the entire text. If the parse completes without reading the entire length of the text, an exception is thrown. If any other problem occurs during parsing, an exception is thrown.

Parameters:

csq - the CharSequence to parse.

Returns:

the unit parsed from the specified character sequence.

Throws:

MeasurementParseException - if any problem occurs while parsing the specified character sequence (e.g. illegal syntax).

java.lang.UnsupportedOperationException - if the UnitFormat is unable to parse.

Since:

2.0