if (txId == null) {
Frame error = Frames.createErrorFrame("Missing transaction id", Headers.create(), "ABORT frames " +
"must contain the 'transaction' header.");
sf.connection().write(error).close();
return;
<BUG>}
Transaction transaction = sf.connection().handler().getTransaction(sf.connection(), txId);
if (transaction == null) {</BUG>
Frame error = Frames.createErrorFrame("Unknown transaction",
Headers.create(Frame.TRANSACTION, txId),

if (txId == null) {
Frame error = Frames.createErrorFrame("Missing transaction id", Headers.create(), "ABORT frames " +
"must contain the 'transaction' header.");
sf.connection().write(error).close();
return;
}
if (! Transactions.INSTANCE.unregisterTransaction(sf.connection(), txId)) {
Frame error = Frames.createErrorFrame("Unknown transaction",
Headers.create(Frame.TRANSACTION, txId),
