CMT question.

Question

weblogic8.1's transaction setting always confuse me. I have some cases, hope I understand right.
          TxDataSource on 8.1, this is set when 'Honor Global Transactions' is set to true. Am I right? this will enable the transaction like what JAVA/JDBC transaction does--set the auto commit to false. This flag need to be set to true either for client initiate transaction using UserTransaction Interface or CMT when there is more than one database action(here I just want to talk about one database).
          Here is my question:
          1).when doing the Client Initiate Transaction, besides this flag, do I still need to set 'Emulate two-phase commit'? the transaction only access one datasource. I don't know how this flag helps since the Drive is non-XA driver.
          2).for CMT, all the user case action are in the Stateless bean method. I have DAO to access database. the DAO will get the connection from the pool. again all DAOs only access one database(DS). the driver is non-XA driver. when the bean method call multipule DAOs, since each DAO will get their own connection, Do I need to set ''Emulate two-phase commit', or Weblogic does some optimization
          3). Also for CMT. If 'Honor Global Transactions' is set to false. when there are multiple database actions in one bean method as in item 2). The transaction scope won't be defined by container, instead, there will be a commit after each DAO call.
          Thanks
          CC.

Answer 1

Vishal Jain - thanks for the reply.
1. The method name is misleading - there are only insert statements in this method.
2. I am using CMT to scope viewEmployee() method with RequiresNew attribute. This method calls DAO object method to do its work. The connection is obtained in the session bean and a reference is available in the DAO to enable it to connect.
3. the DAO never manipulates the connection - only fires SQL and returns - can throw an application or SQL Exception.
4. This will be caught in the session bean's handlers and context.setRollbackOnly(); will be called. This statement does not rollback the changes made to table data, infact it is throwing IllegalStateException - "Cannot call setRollbackOnly() current thread is NOT associated with a transaction"
Pls point out any possible causes.
Thanks in advance.