Restrictions on Read-Only EJBs

Chapter 8 Creating J2EE Applications for BEA WebLogic

Entity EJBs using the read-only concurrency strategy must observe the following restrictions:

They cannot require updates to the EJB data, because WebLogic Server never calls ejbStore() for read-only entity EJBs.
Their transaction attributes must be set to NotSupported (the beans cannot rely on a transaction).
The EJB's method calls must be idempotent. See EJBs in WebLogic Server Clusters for more information.
Because the bean's underlying data may be updated by an external source, calls to ejbLoad() are governed by the deployment parameter, read-timeout-seconds.