static JsonArray parseJsonArray(String jsonString) throws JwtInvalidException {
    try {
      return JsonParser.parse(jsonString).getAsJsonArray();
    } catch (IllegalStateException | JsonParseException | IOException ex) {
      throw new JwtInvalidException("invalid JSON: " + ex);
    }
  }
Helper functions to parse JSON strings, and validate strings.
java_src/src/main/java/com/google/crypto/tink/jwt/JsonUtil.java