⟩ Which of the following statements are true regarding MDBs (Message Driven Beans) on version 6.0 of WebLogic App Server?
a. MDBs support concurrent processing for both Topics and Queues.
b. MDBs support concurrent processing for only Topics.
c. MDBs support concurrent processing for only Queues.
d. MDBs support concurrent processing neither Topics nor Queues.
Choice A is correct. MDBs support concurrent processing for both Topics and Queues. Previously, only concurrent processing for Queues was supported. To ensure concurrency, change the weblogic-ejb-jar.xml deployment descriptor max-beans-in-free-pool setting to >1. If this element is set to more than one, the container will spawn as many threads as specified. WebLogic Server maintains a free pool of EJBs for every stateless session bean and message driven bean class.
The max-beans-in-free-pool element defines the size of this pool. By default, max-beans-in-free-pool has no limit; the maximum number of beans in the free pool is limited only by the available memory.
