docs: public static void delete(File f) {
          if (!f.exists()) {
              return;
          }
          File[] subFiles = f.listFiles();
          if (subFiles != null) {
              for (File sf : subFiles) {
                  delete(sf);
              }
          }
          if (!f.delete()) {
              throw new HazelcastException("Failed to delete " + f);
          }
      }