Acceptable input arguments are Strings or Objects. The Java API provides the method pare with one overload. The result is a member of the UCollationResult or EComparisonResult enums. Acceptable input arguments are UChar * with length of strings, or UnicodeString instances. The C++ API offers the method Collator::compare with several overloads. The result is a UCollationResult constant, which can be one of UCOL_LESS, UCOL_EQUAL or UCOL_GREATER. It requires two UChar * strings and their lengths as parameters, as well as a pointer to a valid UCollator instance. The C API used for comparing two strings is ucol_strcoll. In all other cases (such as quick sort or bubble sort of a moderately-sized list of strings), comparing strings works very well. However, if comparisons should be done repeatedly on a very large number of strings, generating and storing sort keys can improve performance. Comparing two strings is much faster than calculating sort keys for both of them. The ucol_compare function compares one pair of strings at a time. Please refer to the section below on CollationElementIterator for more details. This example demonstrates the instantiation of a collator.įor more sophisticated usage, such as user-controlled language-sensitive text searching, an iterating interface to collation is provided. (The deprecated attributes kh/colHiraganaQuaternary and vt/variableTop are not supported.)įor the old locale extension syntax, the data file’s alias names are used (first alias, if defined, otherwise the name): the language tag syntax, the non-alias names are used, and “true” values can be omitted: “de-u-co-phonebk-kc-kv-space” See the LDML Collation spec, Collation Settings, and the data file listing the valid collation keywords and their values. Keywords and values are case-insensitive. Starting with ICU 54, collation attributes can be specified via locale keywords as well, in the old locale extension syntax or in language tag syntax (“el-u-kf-upper”). See also the list of available collation tailorings in the online ICU Collation Demo. The C API takes a locale ID (or language tag) string argument, C++ takes a Locale object, and Java takes a Locale or ULocale.įor some languages, multiple collation types are available for example, “de-u-co-phonebk” / They can be enumerated via Collator::getKeywordValuesForLocale(). To instantiate a predefined collator, use the APIs ucol_open, createInstance and getInstance for C, C++ and Java codes respectively. (For example, there are no tailorings for the standard sort orders for English, German, French, etc.) The default sort order itself is designed to work well for many languages. In the worst case, the CLDR default set of rules, which is mostly equivalent to the UCA default ordering (DUCET), is used.

Most of the ICU locales have a predefined collator. ICU comes with a large set of already predefined collators that are suited for specific locales. The Collator can then be closed and removed. The Collator can be repeatedly referenced until all collation activities have been performed. The Collator defines the properties and behavior of the sort ordering. To use the Collation Service, you must instantiate a Collator. This section describes some of the usage conventions for the ICU Collation Service API. Instantiating Collators Using Custom Rules.This site uses Just the Docs, a documentation theme for Jekyll. Updating MeasureUnit with new CLDR data.

Macports mingw icu