Can I use transactions within a servlet?

[Joseph Magerramov]

Our software doesn't use EJBs but rather accesses database directly. For example, a certain servlet could call several methods, each of them obtaining a separate connection from the datasource and using it to update database.
Since there are several connections, connection.setAutoCommit(false) obviously won't work. I was wondering if it's possible to execute all this db calls as part of one transaction. Any suggestions or samples would be appreciated.

[David O'Meara]

Check out UserTransactions and TransactionManager. I haven't tried it in WebSphere, let alone in a Servlet or library code, but from memory something like this may work:
The UserTranaction is an interface, the factory to obtain one is registered in JNDI.
It would look like this:

Context ctx = new InitialContext();
UserTransaction ut = (UserTransaction)ctx.lookup("javax.jts.UserTransaction");
ut.begin
try
{
    //do lots of database stuff.
    //the UserTransaction makes sure they happen in a single Transaction
    //commit the transaction at the end
    ut.commit();
}
catch(SQLException sqle)
{
    ut.rollback();
}

Also be aware that it may be bound in JNDI as javax.transaction.UserTransaction, I can't remember...
It is also a common practice to wrap the ut.begin/commit around a single method that does all the SQL.

[David O'Meara]

My appologies, it may also be "java:comp/UserTransaction". I wish I'd written it down. You may want to go looking for it

[Joseph Magerramov]

Thank you David.