@Override
  public Block createForkBlock(Block parent) {
    try {
      List<Transaction> txes = new ArrayList<>();
      Map<ByteArrayWrapper, Long> nonces = new HashMap<>();
      Repository repoSnapshot =
          getBlockchain().getRepository().getSnapshotTo(parent.getStateRoot());
      for (PendingTx tx : submittedTxes) {
        ByteArrayWrapper senderW = new ByteArrayWrapper(tx.sender.getAddress());
        Long nonce = nonces.get(senderW);
        if (nonce == null) {
          BigInteger bcNonce = repoSnapshot.getNonce(tx.sender.getAddress());
          nonce = bcNonce.longValue();
        }
        nonces.put(senderW, nonce + 1);

        byte[] toAddress =
            tx.targetContract != null ? tx.targetContract.getAddress() : tx.toAddress;

        Transaction transaction =
            new Transaction(
                ByteUtil.longToBytesNoLeadZeroes(nonce),
                ByteUtil.longToBytesNoLeadZeroes(gasPrice),
                ByteUtil.longToBytesNoLeadZeroes(gasLimit),
                toAddress,
                ByteUtil.bigIntegerToBytes(tx.value),
                tx.data);
        transaction.sign(tx.sender.getPrivKeyBytes());
        if (tx.createdContract != null) {
          tx.createdContract.setAddress(transaction.getContractAddress());
        }
        txes.add(transaction);
      }
      Block b = getBlockchain().createNewBlock(parent, txes, Collections.EMPTY_LIST);
      Ethash.getForBlock(b.getNumber()).mineLight(b).get();
      ImportResult importResult = getBlockchain().tryToConnect(b);
      if (importResult != ImportResult.IMPORTED_BEST
          && importResult != ImportResult.IMPORTED_NOT_BEST) {
        throw new RuntimeException(
            "Invalid block import result " + importResult + " for block " + b);
      }
      submittedTxes.clear();
      return b;
    } catch (InterruptedException | ExecutionException e) {
      throw new RuntimeException(e);
    }
  }
 private void submitNewTx(PendingTx tx) {
   submittedTxes.add(tx);
   if (autoBlock) {
     createBlock();
   }
 }