code: import org.apache.lucene.util.fst.FST;
  import pl.sdadas.fstlexicon.fst.FSTUtils;
  
  import java.io.File;
  import java.io.IOException;
  import java.nio.charset.StandardCharsets;
  import java.nio.file.Files;
  import java.nio.file.StandardOpenOption;
  import java.util.SortedMap;
  import java.util.TreeMap;
  
  /**
   * @author Sławomir Dadas
   */
  public class CreateTestData {
  
      public static void main(String [] args) throws IOException {
          FST<Long> fst = FSTUtils.build(createMap());
          fst.save(new File("food.fst").toPath());
          byte[] meta = createMetaJson().getBytes(StandardCharsets.UTF_8);
          Files.write(new File("meta.json").toPath(), meta, StandardOpenOption.CREATE);
      }
  
      private static SortedMap<String, Long> createMap() {
          SortedMap<String, Long> res = new TreeMap<>();
          res.put("pizza", 0L);
          res.put("gnocchi", 0L);
          res.put("pasta", 0L);
          res.put("pierogi", 1L);
          res.put("bigos", 1L);
          res.put("kiełbasa", 1L);
          res.put("paella", 2L);
          res.put("gazpacho", 2L);
          res.put("chorizo", 2L);
          res.put("sushi", 3L);
          res.put("ramen", 3L);
          res.put("miso", 3L);
          return res;
      }
  
      private static String createMetaJson() {
          return "{\"food\":[\"italian\", \"polish\", \"spanish\", \"japanese\", \"other\"]}";
      }
  }
  