WebLogic Server Internationalization (i18n) covers the internationalization of messages written to the WebLogic Server log.
Localization (l10n) of i18n text is supported through the Localizer interface. L10n support is provided in the form of ResourceBundles, which are derived from text-based message catalogs located in weblogic/msgcat.
The message catalogs are XML files that define each message. The catalogs for the base locale are defined by the msgcat.dtd document type definition. Catalogs which provide different localizations of the base catalogs are defined in msgcat subdirectories named after the locale (for example, weblogic/msgcat/ja), and use the l10n_msgcat.dtd document type definition.
A message catalog file may define log messages or simple text. A single catalog may not include definitions for more than one type of message. Each catalog should only contain message definitions for a particular subsystem. Subsystems can be further subdivided into smaller subsystems. For instance, The EJB messages might all be in a single subsystem or be further divided into the various EJB packages.
The weblogic.i18ngen utility is used to parse and process the message catalog files, producing Localizer classes for each catalog. Localizer classes are packaged according to the l10n_package attribute.
Localizer is a class used to look up the various elements of a message definition.