ChoiceFormat ChoiceFormat is a concrete class used to map strings to ranges of numbers and to handle plural words and name series in user messages. Searching and Sorting Sorting and searching non-English text presents a number of challenges that many English speakers are unaware of. Sometimes the accented form of a letter is treated as a distinct letter for the purposes of comparison. In some cases, an accented letter is treated as if it were two letters. Searching and sorting is done through collation using the Collator class and its sub-classes RuleBasedCollator and CollationElementIterator as well as the CollationKey object.
Collation determines the proper sort sequence for two or more natural language strings.
It also can determine if two strings are equivalent for the purpose of searching. ICU provides four collation classes for sorting and searching natural language text according to locale-specific rules. Collator Collator is the abstract base class of all classes that compare strings. CollationElementIterator CollationElementIterator is a concrete iterator class that provides an iterator for stepping through each character of a locale-specific string according to the rules of a specific collator object. RuleBasedCollator RuleBasedCollator is the only built-in implementation of the collator.