Class ICUCollationField


public class ICUCollationField extends FieldType
Field for collated sort keys. These can be used for locale-sensitive sort and range queries.

This field can be created in two ways:

  • Based upon a system collator associated with a Locale.
  • Based upon a tailored ruleset.

Using a System collator:

  • locale: RFC 3066 locale ID (mandatory)
  • strength: 'primary','secondary','tertiary', 'quaternary', or 'identical' (optional)
  • decomposition: 'no', or 'canonical' (optional)

Using a Tailored ruleset:

  • custom: UTF-8 text file containing rules supported by RuleBasedCollator (mandatory)
  • strength: 'primary','secondary','tertiary', 'quaternary', or 'identical' (optional)
  • decomposition: 'no' or 'canonical' (optional)

Expert options:

  • alternate: 'shifted' or 'non-ignorable'. Can be used to ignore punctuation/whitespace.
  • caseLevel: 'true' or 'false'. Useful with strength=primary to ignore accents but not case.
  • caseFirst: 'lower' or 'upper'. Useful to control which is sorted first when case is not ignored.
  • numeric: 'true' or 'false'. Digits are sorted according to numeric value, e.g. foobar-9 sorts before foobar-10
  • variableTop: single character or contraction. Controls what is variable for 'alternate'
See Also:
  • Collator
  • ULocale
  • RuleBasedCollator