This directory is used for building our Android ICU data file.

1. To generate ICU data files:run the icu_dat_generator.py script.
   The command is:
     ./icu_dat_generator.py [-v] [-h]

2. To add a resource to Android ICU data file: insert an entry to
   icu-data-default.txt in external/icu4c/stubdata then
   run icu_dat_generator.py.
   For example, to add French collation, you need to
   a. Add an entry, "coll/fr.res", into external/icu4c/stubdata/icu-data-default.txt
   b. run "./icu_dat_generator.py".

3. Add a new resource or modify existing ICU resource definition:
   Note: This is a rare case. You should talk to ICU team first if it is a bug
   in ICU resource or a feature enhancement before making such changes.
   If you would like to add existing ICU resource to Android, please check #2.
   a. Create or change the text format resource files under external/icu4c/data.
   b. Make a temporary directory for ICU build.
      i.e. mkdir external/icu4c/icuBuild
   c. cd to ICU build directory.
      i.e. cd external/icu4c/icuBuild
   d. Run external/icu4c/runConfigureICU with "Linux" option to generate the
      makefile.
      i.e. $ANDROID_BUILD_TOP/external/icu4c/runConfigureICU Linux
   e. make -j2
   f. The new icudtXXl.dat is under data/out/tmp and the individual resources are
      under data/out/build/icudtXXl
      For example, you can find data/out/tmp/icudtXXl.dat and data/out/build/icudtXX48l/*.res.
   g. Copy the new icudtXXl.dat over $ANDROID_BUILD_TOP/external/icu4c/stubdata/icudtXXl-all.dat.
      i.e. cp data/out/tmp/icudtXXl.dat $ANDROID_BUILD_TOP/external/icu4c/stubdata/icudtXXl-all.dat.
   h. Check #1 or #2 to replace or add resource to ICU.
   i. Clean up ICU build directory.
   j. Discuss with icu-team how to include the change to public ICU.

Locale Resource Files:
- icudtXXl-all.dat contains the resources in packed
  form. It includes everything that comes with
  a vanilla ICU release. icu_dat_generator.py uses this file to generate
  custom build dat files.

- cnv/*.cnv are the additional encodings required by Android.
  These are
  - gsm-03.38-2000.cnv
  - iso-8859_16-2001.cnv
  - docomo-shift_jis-2012.cnv
  - kddi-jisx-208-2007.cnv
  - kddi-shift_jis-2012.cnv
  - softbank-jisx-208-2007.cnv
  - softbank-shift_jis-2012.cnv

- Text format ICU resource files are under external/icu4c/data directory.
  Binary resource files are packaged in external/icu4c/stubdata/icudtXXl-all.dat.
  If you have bug fixes to apply or want to examine individual resource sizes,
  you can run icupkg utility to extract icudtXXl-all.dat into a temporary directory.
  For example:
  cd $ANDROID_BUILD_TOP/external/icu4c/stubdata
  cp icudtXXl-all.dat icudtXXl.dat
  mkdir tempDir
  $ANDROID_BUILD_TOP/prebuilt/linux-x86_64/icu-4.8/icupkg  icudtXXl.dat -x "*" -d tempDir

Run ICU tests:
ICU tests are not part of Android build. If you change the ICU code or data,
it is highly recommended to run ICU tests.
 1. Remove the flag "-R" in external/icu4c/data/Makefile.in.
    "Reverse collation keys" tables are not included in ICU data on Android. To
    pass ICU collation tests, you need to delete the flag "-R" in Makefile.in.
    Search for " -R" under "### collation res" section in external/icu4c/data/Makefile.in,
    delete all of them.
 2. Make a temporary directory for ICU build.
    i.e. mkdir external/icu4c/icuBuild
 3. cd to ICU build directory.
    i.e. cd external/icu4c/icuBuild
 4. Run external/icu4c/runConfigureICU with "Linux" option to generate the makefile.
    i.e. $ANDROID_BUILD_TOP/external/icu4c/runConfigureICU Linux
 5. make -j2 check
 6. Check the result. Ignore the errors from tsconv.