JDBC transactions

I wanted to make sure before I attempt it:

If I'm using the JDBC driver, I don't have to use explicit transaction
calls. That is, I don't have to sent the statements "BEGIN TRANSACTION" and
"END".

Instead, I have to do con.setAutoCommit(false), and then, the next SQL call
will initiate a transaction, which I end by using con.commit() or
con.rollback().

That's the documented behavior of JDBC, and what I'm asking is whether (a)
I'm correct in my interpretation, and (b) whether the current JDBC driver
provided with PostgreSQL 6.2.1 in fact behaves like this.

Herouth