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Gotchas

The following are some “gotchas” to help you with your implementation:

• If writing CMTD Session beans, resource manager transaction methods (such as connection.commit()) must not be used.

• The ejbCreate() and ejbRemove() lifecycle methods for Session beans (and Message-driven beans) are performed with unspecified transaction context.

• The collection returned by the getter method for a cmr-field cannot be used outside of the transaction in which it was materialized (see EJB specification, section 10.3.8).

• If using a SQLj Part 0 compiler, make sure that the vendor offers adequate support for the generated code to run within the J2EE environment.

• If using SQLj Part 1 or Part 2, be sure to do some performance benchmarking first. This is a new technology ...