code: private static void outputFile(File dstFile, Map<String, SortedMap<String, ZoneRules>> allBuiltZones,
              Set<String> allRegionIds, Set<ZoneRules> allRules, SortedMap<LocalDate, Byte> leapSeconds) {
          JarOutputStream jos = null;
          try {
              jos = new JarOutputStream(new FileOutputStream(dstFile));
              outputTzdbEntry(jos, allBuiltZones, allRegionIds, allRules);
          } catch (Exception ex) {
              System.out.println("Failed: " + ex.toString());
              ex.printStackTrace();
              System.exit(1);
          } finally {
              if (jos != null) {
                  try {
                      jos.close();
                  } catch (IOException ex) {
                      // ignore
                  }
              }
          }
      }
docs: Outputs the file.