private void handleNewExternalTransactionsInt(Collection<TransactionEx> transactions) throws WapiException { // Transform and put into two arrays with matching indexes ArrayList<TransactionEx> texArray = new ArrayList<TransactionEx>(transactions.size()); ArrayList<Transaction> txArray = new ArrayList<Transaction>(transactions.size()); for (TransactionEx tex : transactions) { try { txArray.add(Transaction.fromByteReader(new ByteReader(tex.binary))); texArray.add(tex); } catch (TransactionParsingException e) { // We hit a transaction that we cannot parse. Log but otherwise ignore it _logger.logError("Received transaction that we cannot parse: " + tex.txid.toString()); continue; } } // Grab and handle parent transactions fetchStoreAndValidateParentOutputs(txArray); // Store transaction locally for (int i = 0; i < txArray.size(); i++) { _backing.putTransaction(texArray.get(i)); onNewTransaction(texArray.get(i), txArray.get(i)); } }
protected void handleNewExternalTransactions(Collection<TransactionEx> transactions) throws WapiException { if (transactions.size() <= MAX_TRANSACTIONS_TO_HANDLE_SIMULTANEOUSLY) { handleNewExternalTransactionsInt(transactions); } else { // We have quite a list of transactions to handle, do it in batches ArrayList<TransactionEx> all = new ArrayList<TransactionEx>(transactions); for (int i = 0; i < all.size(); i += MAX_TRANSACTIONS_TO_HANDLE_SIMULTANEOUSLY) { int endIndex = Math.min(all.size(), i + MAX_TRANSACTIONS_TO_HANDLE_SIMULTANEOUSLY); List<TransactionEx> sub = all.subList(i, endIndex); handleNewExternalTransactionsInt(sub); } } }
protected boolean monitorYoungTransactions() { Collection<TransactionEx> list = _backing.getYoungTransactions(5, getBlockChainHeight()); if (list.isEmpty()) { return true; } List<Sha256Hash> txids = new ArrayList<Sha256Hash>(list.size()); for (TransactionEx tex : list) { txids.add(tex.txid); } CheckTransactionsResponse result; try { result = _wapi.checkTransactions(new CheckTransactionsRequest(txids)).getResult(); } catch (WapiException e) { postEvent(Event.SERVER_CONNECTION_ERROR); _logger.logError("Server connection failed with error code: " + e.errorCode, e); // We failed to check transactions return false; } for (TransactionStatus t : result.transactions) { if (!t.found) { // We have a transaction locally that does not exist in the // blockchain. Must be a residue due to double-spend or malleability _backing.deleteTransaction(t.txid); continue; } TransactionEx tex = _backing.getTransaction(t.txid); Preconditions.checkNotNull(tex); if (tex.height != t.height || tex.time != t.time) { // The transaction got a new height or timestamp. There could be // several reasons for that. It got a new timestamp from the server, // it confirmed, or might also be a reorg. TransactionEx newTex = new TransactionEx(tex.txid, t.height, t.time, tex.binary); System.out.println("Replacing:\n" + tex.toString() + "\nWith:\n" + newTex.toString()); postEvent(Event.TRANSACTION_HISTORY_CHANGED); _backing.deleteTransaction(tex.txid); _backing.putTransaction(newTex); } } return true; }
private void fetchStoreAndValidateParentOutputs(ArrayList<Transaction> transactions) throws WapiException { Map<Sha256Hash, TransactionEx> parentTransactions = new HashMap<Sha256Hash, TransactionEx>(); Map<OutPoint, TransactionOutputEx> parentOutputs = new HashMap<OutPoint, TransactionOutputEx>(); // Find list of parent outputs to fetch Collection<Sha256Hash> toFetch = new HashSet<Sha256Hash>(); for (Transaction t : transactions) { for (TransactionInput in : t.inputs) { if (in.outPoint.hash.equals(OutPoint.COINBASE_OUTPOINT.hash)) { // Coinbase input, so no parent continue; } TransactionOutputEx parentOutput = _backing.getParentTransactionOutput(in.outPoint); if (parentOutput != null) { // We already have the parent output, no need to fetch the entire // parent transaction parentOutputs.put(parentOutput.outPoint, parentOutput); continue; } TransactionEx parentTransaction = _backing.getTransaction(in.outPoint.hash); if (parentTransaction != null) { // We had the parent transaction in our own transactions, no need to // fetch it remotely parentTransactions.put(parentTransaction.txid, parentTransaction); } else { // Need to fetch it toFetch.add(in.outPoint.hash); } } } // Fetch missing parent transactions if (toFetch.size() > 0) { GetTransactionsResponse result = _wapi.getTransactions(new GetTransactionsRequest(Wapi.VERSION, toFetch)).getResult(); for (TransactionEx tx : result.transactions) { // Verify transaction hash. This is important as we don't want to // have a transaction output associated with an outpoint that // doesn't match. // This is the end users protection against a rogue server that lies // about the value of an output and makes you pay a large fee. Sha256Hash hash = HashUtils.doubleSha256(tx.binary).reverse(); if (hash.equals(tx.txid)) { parentTransactions.put(tx.txid, tx); } else { _logger.logError( "Failed to validate transaction hash from server. Expected: " + tx.txid + " Calculated: " + hash); throw new RuntimeException( "Failed to validate transaction hash from server. Expected: " + tx.txid + " Calculated: " + hash); } } } // We should now have all parent transactions or parent outputs. There is // a slight probability that one of them was not found due to double // spends and/or malleability and network latency etc. // Now figure out which parent outputs we need to persist List<TransactionOutputEx> toPersist = new LinkedList<TransactionOutputEx>(); for (Transaction t : transactions) { for (TransactionInput in : t.inputs) { if (in.outPoint.hash.equals(OutPoint.COINBASE_OUTPOINT.hash)) { // coinbase input, so no parent continue; } TransactionOutputEx parentOutput = parentOutputs.get(in.outPoint); if (parentOutput != null) { // We had it all along continue; } TransactionEx parentTex = parentTransactions.get(in.outPoint.hash); if (parentTex != null) { // Parent output not found, maybe we already have it parentOutput = TransactionEx.getTransactionOutput(parentTex, in.outPoint.index); toPersist.add(parentOutput); continue; } _logger.logError("Parent transaction not found: " + in.outPoint.hash); } } // Persist for (TransactionOutputEx output : toPersist) { _backing.putParentTransactionOutput(output); } }