code: public char[] getID() {
          try {
              char[] keyChars = this.readKeyChars();
              NKey nkey =  NKey.fromSeed(keyChars);
              char[] pubKey = nkey.getPublicKey();
              nkey.clear();
              return pubKey;
          } catch (Exception exp) {
              throw new IllegalStateException("problem getting public key", exp);
          }
      }
docs: getID should return a public key associated with a client key known to the server.
  If the server is not in nonce-mode, this array can be empty.
  
  @return the public key as a char array