@NotNull public static String sha1(@NotNull File keyStoreFile) throws Exception {
  return sha1(keyStoreFile,null,null);
}

@ NotNull public static String sha1 ( @ NotNull File keyStoreFile ) throws Exception { return sha1 ( keyStoreFile , null , null ) ; }
get the sha1 hash of the first signing certificate inside a keystore , encoded as base16 ( each byte separated by ' : ' ) .
