code: private static void outputTzdbEntry(
              JarOutputStream jos, Map<String, SortedMap<String, ZoneRules>> allBuiltZones,
              Set<String> allRegionIds, Set<ZoneRules> allRules) {
          // this format is not publicly specified
          try {
              jos.putNextEntry(new ZipEntry("org/threeten/bp/TZDB.dat"));
              outputTzdbDat(jos, allBuiltZones, allRegionIds, allRules);
              jos.closeEntry();
          } catch (Exception ex) {
              System.out.println("Failed: " + ex.toString());
              ex.printStackTrace();
              System.exit(1);
          }
      }
docs: Outputs the timezone entry in the JAR file.