org.apache.sis.measure

Class RangeFormat

Object

Format

RangeFormat

All Implemented Interfaces:

Serializable, Cloneable

public class RangeFormat
extends Format

Parses and formats Range instances according the given locale. This class complies to the format described in the ISO 31-11 standard, except that the minimal and maximal values are separated by the "…" character instead than coma. More specifically, the format is defined as below:

• If the range is empty, then the range is represented by "{}".
• Otherwise if the minimal value is equals to the maximal value, then that single value is formatted inside braces as in "{value}".
• Otherwise the minimal and maximal values are formatted inside bracket or parenthesis, depending on whether each endpoint is inclusive or exclusive:
  • "[min … max]" if both endpoints are inclusive (closed interval);
  • "(min … max)" if both endpoints are exclusive (open interval);
  • or a mix of both styles if an endpoint is inclusive while the other is exclusive.
  The "∞" symbol is used in place of min or max for unbounded ranges.

If the range to format is an instance of Measurement­Range, then the unit of measurement is appended except for empty ranges.

Lenient parsing

At parsing time, the above formatting rules are relaxed as below:

• Empty ranges can be represented by "[]"or "()" in addition to the standard "{}".
• The braces are optional for singleton values, i.e. "value" is accepted as well as "{value}".

Range type and type of range elements

The kind of ranges created by the parse(…) methods is determined by the type of range elements:

• If the elements type is assignable to Date, then the parse(…) methods will create Range<Date> objects.
• If the elements type is assignable to Number, then:
  • If the text to parse contains a unit of measurement, then the parse(…) methods will create Measurement­Range objects.
  • Otherwise the parse(…) methods will create Number­Range objects.

Since:

0.3

See Also:

Range.to­String(), Wikipedia: ISO 31-11, Serialized Form

Defined in the sis-utility module

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RangeFormat.Field Constants that are used as attribute keys in the iterator returned from format­To­Character­Iterator(Object).

Field Summary

Fields

Modifier and Type	Field and Description
protected Format	elementFormat The format to use for parsing and formatting the range components.
protected Class<?>	elementType The type of the range components.
protected UnitFormat	unitFormat The format for unit of measurement, or null if none.

Constructor Summary

Constructors

Constructor and Description
RangeFormat() Creates a new format for parsing and formatting number ranges using the default locale.
RangeFormat(Locale locale) Creates a new format for parsing and formatting number ranges using the given locale.
RangeFormat(Locale locale, Class<?> elementType) Creates a new format for parsing and formatting ranges of the given element type using the given locale.
RangeFormat(Locale locale, TimeZone timezone) Creates a new format for parsing and formatting Range<Date> using the given locale and timezone.

Method Summary

Modifier and Type	Method and Description
RangeFormat	clone() Returns a clone of this range format.
StringBuffer	format(Object range, StringBuffer toAppendTo, FieldPosition pos) Formats a Range and appends the resulting text to a given string buffer.
AttributedCharacterIterator	formatToCharacterIterator(Object range) Formats a range as an attributed character iterator.
String	getElementPattern(boolean localized) Returns the pattern used by element­Format for formatting the minimum and maximum values.
boolean	isAlternateForm() Returns true if this Range­Format shall use the alternate form at formatting time.
Range<?>	parse(String source) Parses text from the given string to produce a range.
Range<?>	parse(String source, ParsePosition pos) Parses text from a string to produce a range.
Object	parseObject(String source) Parses text from a string to produce a range.
Object	parseObject(String source, ParsePosition pos) Parses text from a string to produce a range.
void	setAlternateForm(boolean alternateForm) Sets whether this Range­Format shall use the alternate form at formatting time.
void	setElementPattern(String pattern, boolean localized) Sets the pattern to be used by element­Format for formatting the minimum and maximum values.

Methods inherited from class Format

format

Methods inherited from class Object

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

Field Detail

elementType

protected final Class<?> elementType

The type of the range components. Valid types are Number, Angle, Date or a subclass of those types. This value determines the kind of range to be created by the parse method:

• Number­Range<?> if the element type is assignable to Number or Angle.
• Range<Date> if the element type is assignable to Date.

See Also:

Range.get­Element­Type()

elementFormat

protected final Format elementFormat

The format to use for parsing and formatting the range components. The format is determined from the element type:

• Angle­Format if the element type is assignable to Angle.
• Number­Format if the element type is assignable to Number.
• Date­Format if the element type is assignable to Date.

unitFormat

protected final UnitFormat unitFormat

The format for unit of measurement, or null if none. This is non-null if and only if element­Type is assignable to Number but not to Angle.

Constructor Detail

RangeFormat

public RangeFormat()

Creates a new format for parsing and formatting number ranges using the default locale.

RangeFormat

public RangeFormat(Locale locale)

Creates a new format for parsing and formatting number ranges using the given locale.

Parameters:

locale - the locale for parsing and formatting range components.

RangeFormat

public RangeFormat(Locale locale,
                   TimeZone timezone)

Creates a new format for parsing and formatting Range<Date> using the given locale and timezone.

Parameters:

locale - the locale for parsing and formatting range components.

timezone - the timezone for the date to be formatted.

RangeFormat

public RangeFormat(Locale locale,
                   Class<?> elementType)
            throws IllegalArgumentException

Creates a new format for parsing and formatting ranges of the given element type using the given locale. The element type is typically Date.class or some subclass of Number.class.

Parameters:

locale - the locale for parsing and formatting range components.

element­Type - the type of range components.

Throws:

Illegal­Argument­Exception - if the given type is not recognized by this constructor.

Method Detail

getElementPattern

public String getElementPattern(boolean localized)

Returns the pattern used by element­Format for formatting the minimum and maximum values. If the element format does not use pattern, returns null.

Parameters:

localized - true for returning the localized pattern, or false for the unlocalized one.

Returns:

the pattern, or null if the element­Format doesn't use pattern.

See Also:

Decimal­Format.to­Pattern(), Simple­Date­Format.to­Pattern(), Angle­Format.to­Pattern()

setElementPattern

public void setElementPattern(String pattern,
                              boolean localized)

Sets the pattern to be used by element­Format for formatting the minimum and maximum values.

Parameters:

pattern - the new pattern.

localized - true if the given pattern is localized.

Throws:

Illegal­State­Exception - if the element­Format does not use pattern.

See Also:

Decimal­Format.apply­Pattern(String), Simple­Date­Format.apply­Pattern(String), Angle­Format.apply­Pattern(String)

isAlternateForm

public boolean isAlternateForm()

Returns true if this Range­Format shall use the alternate form at formatting time. The alternate form expresses open intervals like ]a…b[ instead of (a…b).

This flag as no effect on parsing, since the parser accepts both forms.

Returns:

true for using the alternate format instead of the default format.

setAlternateForm

public void setAlternateForm(boolean alternateForm)

Sets whether this Range­Format shall use the alternate form at formatting time.

Parameters:

alternate­Form - true for using the alternate format, or false for using the default format.

format

public StringBuffer format(Object range,
                           StringBuffer toAppendTo,
                           FieldPosition pos)

Formats a Range and appends the resulting text to a given string buffer. See the class javadoc for a description of the format.

Specified by:

format in class Format

Parameters:

range - the Range object to format.

to­Append­To - where the text is to be appended.

pos - identifies a field in the formatted text, or null if none.

Returns:

the string buffer passed in as to­Append­To, with formatted text appended.

Throws:

Illegal­Argument­Exception - if this formatter can not format the given object.

formatToCharacterIterator

public AttributedCharacterIterator formatToCharacterIterator(Object range)

Formats a range as an attributed character iterator. Callers can iterate and queries the attribute values as in the following example:

AttributedCharacterIterator it = rangeFormat.formatToCharacterIterator(myRange);
for (char c=it.first(); c!=AttributedCharacterIterator.DONE; c=c.next()) {
    // 'c' is a character from the formatted string.
    if (it.getAttribute(RangeFormat.Field.MIN_VALUE) != null) {
        // If we enter this block, then the character 'c' is part of the minimal value,
        // This field extends from it.getRunStart(MIN_VALUE) to it.getRunLimit(MIN_VALUE).
    }
}

Alternatively, if the current iterator index is before the start of the minimum value field, then the starting position of that field can be obtained directly by it.get­Run­Limit(MIN_VALUE). If the current iterator index is inside the minimum value field, then the above method call will rather returns the end of that field. The same strategy works for other all fields too.

The returned character iterator contains all Number­Format.Field, Date­Format.Field or Angle­Format.Field attributes in addition to the Range­Format.Field ones. Consequently the same character may have more than one attribute.

In Apache SIS implementation, the returned character iterator also implements the Char­Sequence interface for convenience.

Overrides:

format­To­Character­Iterator in class Format

Parameters:

range - the Range object to format.

Returns:

a character iterator together with the attributes describing the formatted value.

Throws:

Illegal­Argument­Exception - if value if not an instance of Range.

parseObject

public Object parseObject(String source)
                   throws ParseException

Parses text from a string to produce a range. The default implementation delegates to parse(String) with no additional work.

Overrides:

parse­Object in class Format

Parameters:

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

Returns:

a range parsed from the string.

Throws:

Parse­Exception - if the given string can not be fully parsed.

parseObject

public Object parseObject(String source,
                          ParsePosition pos)

Parses text from a string to produce a range. The default implementation delegates to parse(String, Parse­Position) with no additional work.

Specified by:

parse­Object in class Format

Parameters:

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

pos - index and error index information as described above.

Returns:

a range parsed from the string, or null in case of error.

parse

public Range<?> parse(String source)
               throws ParseException

Parses text from the given string to produce a range. This method use the full string. If there is some unparsed characters after the parsed range, then this method thrown an exception.

Parameters:

source - the text to parse.

Returns:

the parsed range (never null).

Throws:

Parse­Exception - if the given string can not be fully parsed.

parse

public Range<?> parse(String source,
                      ParsePosition pos)

Parses text from a string to produce a range. The method attempts to parse text starting at the index given by pos. If parsing succeeds, then the index of pos is updated to the index after the last character used, and the parsed range is returned. If an error occurs, then the index of pos is not changed, the error index of pos is set to the index of the character where the error occurred, and null is returned.

Parameters:

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

pos - index and error index information as described above.

Returns:

a range parsed from the string, or null in case of error.

clone

public RangeFormat clone()

Returns a clone of this range format.

Overrides:

clone in class Format

Returns:

a clone of this range format.