The ant build.xml file takes care of copying some CLDR test data directories to both the ICU4C and ICU4J source trees. To add more directories to the list, modify the cldrTestData
fileset.
The cldr-to-icu directory contains tools to convert from CLDR's XML data to ICU resource files.
See cldr-to-icu/README.txt and cldr-icu-readme.txt for more information.