xref: /aosp_15_r20/system/timezone/input_tools/android/tzlookup_generator/README.android (revision 2fd832c65f8b41db7ddb4ac802b9196762fe4888)
1This tool generates the tzlookup.xml file from the countryzones.txt (proto
2text) file. tzlookup.xml is used to associate zones with regions/countries. The
3tool uses ICU4J and IANA data to synthesize some time zone metadata.
4
5Besides tzlookup.xml, the tool also generates a tzids.prototxt file
6containing information about zone IDs, id links and "functionally identical"
7zones[1] within each known country. These can be used to map time zone IDs to
8Android's preferred set. This duplicates information from the tzlookup.xml, but
9it is easier to use from host tools than Android's tzlookup.xml's format.
10
11[1] i.e. zones that differed in the past but were "folded in" to other zones
12and are not distinct for future times according to IANA or ICU/CLDR.
13