Set this property to a supported locale name when using one of the Derby tools, if you want another locale than the system default locale. The locale determines the localized display format for numbers, dates, times and timestamps, as well as the language of the messages from the Derby tools. Note that some pages in the Derby documentation guides refer to a "locale" as a "territory".
where derbyval is a supported locale name, in the form ll_CC, where ll is the two-letter language code, and CC is the two-letter country code; for example, ja_JP.
The following command specifies to run ij using the Japanese territory (derby.ui.locale=ja_JP) using Japanese Latin Kanji mixed encoding (codeset=Cp939):
java -Dderby.ui.locale=ja_JP -Dderby.ui.codeset=Cp939 -Dij.protocol=jdbc:derby: org.apache.derby.tools.ij
To see a full list of ISO-639 codes, go to http://www.ics.uci.edu/pub/ietf/http/related/iso639.txt.
A copy of ISO-3166 can be found at http://www.chemie.fu-berlin.de/diverse/doc/ISO_3166.html.