Enthuware

c.setAutoCommit(false) is set to false and we are neither setting it to true nor using c.commit(),will commit happen?

No, it will not be committed but the last comment in the given code says, "// continue with existing transaction", so you don't really have to worry about whether the transaction will be committed or not after that line.

Just to confirm, if there was no if statement at all and you had:

c.rollback(sp1); //*
c.rollback();

at the end, then line * would be redundant as the second line would just undo all?

Yes, that is correct.