International Components for Unicode

Infobox_Software
name = International Components for Unicode



caption =
developer = IBM and many other companies.
latest_release_version = 4.0
latest_release_date = release date|2008|07|02
latest_preview_version =
latest_preview_date =
operating_system = Cross-platform
programming_language = C/C++ and Java
genre = libraries for Unicode and Globalization
license = MIT License
website = http://www.icu-project.org/

International Components for Unicode (ICU) is an open source project of mature C/C++ and Java libraries for Unicode support, software internationalization and software globalization. ICU is widely portable to many operating systems and environments. It gives applications the same results on all platforms and between C/C++ and Java software. The ICU project is an open source development project that is sponsored, supported and used by IBM and many other companies.

Some of the services that it provides are the following.

* Text: Unicode text handling, full character properties and character set conversions
* Analysis: Unicode regular expressions; full Unicode sets; character, word and line boundaries
* Comparison: Language sensitive collation and searching
* Transformations: normalization, upper/lowercase, script transliterations
* Locales: Comprehensive locale data and resource bundle architecture, via the Common Locale Data Repository
* Complex Text Layout: Arabic, Hebrew, Indic and Thai
* Time: Multi-calendar and time zone
* Formatting and Parsing: dates, times, numbers, currencies, messages and rule based

ICU provides much richer internationalization facilities than the standard libraries for C or C++, and most operating systems.

Origin and Development

ICU is descended from C++ frameworks produced by Taligent in the mid 1990s. Soon after Taligent became part of IBM in early 1996, Sun Microsystems decided that Java, then in its infancy, "was missing international support. Taligent had great international technology, talented engineers, and a location about 100 meters from Sun's JavaSoft division in Cupertino, California. IBM arranged for Taligent's Text and International group to contribute international classes to Sun's Java Development Kit."cite web |url=http://www.icu-project.org/docs/papers/history_of_java_internationalization.html | title=Getting Java ready for the world: A brief history of IBM and Sun's internationalization efforts |author=Laura Werner |year=1999] Some of the code for text processing, date formatting, etc., was rewritten in Java and became the JDK 1.1 internationalization APIs. A large portion of this code still exists in the Javadoc:SE|package=java.text|java/text and Javadoc:SE|package=java.util|java/util packages. Further internationalization features were added with each later release of Java.

IBM programmers then rewrote the Java internationalization classes in C++ and later ported some classes to C. The C++/C version of ICU is known as ICU4C. The ICU project also provides ICU4J ("ICU for Java"), which adds features not present in the standard Java libraries. ICU4C and ICU4J are kept as similar as possible (though not identical — for example, ICU4C includes a character converter API). Both have been enhanced over time to support new facilities and new features of Unicode. ICU was released as an open source project in 1999 under the name "IBM Classes for Unicode." It was later renamed to "International Components For Unicode."

See also

* Uniscribe
* OpenType
* Apple Advanced Typography
* Pango
* Graphite (SIL)

References

External links

* [http://www.icu-project.org/ ICU website]