Using DataSource from a user-defined thread

Question

Using Websphere 5.1.1, I have a servlet that launches a special thread, which accesses a database (through a DataSource).
It's unusual, but it's a requirement.
So it would in the lines of (ommitting error handling):
public class MyServlet extends HttpServlet
    public void doGet(HttpServletRequest req, HttpServletResponse resp){
        InitialContext ctx=new InitialContext();
        final DataSource ds=(DataSource)
               ctx.lookup("java:comp/env/myDataSourceRef");
        new Thread(){
             public void run(){
                  Connection con=ds.getConnection();
                  ... run some JDBC code
                  con.close();
        }.start();
}When running this, I get a warning :
"J2CA0075W: An active transaction should be present while processing method initializeForUOW"
According to IBM, that follows J2EE spec, because
Eventually (i.e. J2EE 1.4) spun threads from a Servlet accessing a database outside of a transaction will not be supported(Quoting from: http://www-1.ibm.com/support/docview.wss?rs=180&context=SSEQTP&q=J2CA0075W&uid=swg21109248).
But then, if the problem is a lack of transaction, how can one guarantee a transaction is present ?
I have already tried the following, in vain:
1) Making sure the datasource is registered as a web reference (in web.xml), with transaction isloation level set to READ_COMMITTED.
2) Invoking con.setAutoCommit(false), which is probably not recommended, but I tried it anyway.
3) I've considered moving the call "con=ds.getConnection" out of the thread, and into "doGet". However, my application logic won't allow it.
Would anyone happen to know how to make sure such a transaction is present ?
Thanks very much.

Answer 1

A map with a constant or mapping input parameter that uses a function should call the function one time.
There was a bug(5663912) in 10.2.0.1 that was fixed in 10.2.0.2. If the SQL statement is using a PLSQL variable which has the initial value of the function result then this is working OK, if the SQL statement calls a 'GET_' function which in turn executes your function then you are not using the fix.
Cheers
David
(The intermediate code generation shown in the mapping editor is not the full blown code generator).