Figure showing a somewhat more complex EJB application, with several clients and a database. Three clients talk to a session bean called Calendar Manager, which initiates actions by three entity beans: Activity, User, and To Do Item. Those three entity beans and the EJB container talk to the database. A fourth client sends a message to a message queue. The message-driven bean Request Room picks up the message and initiates activity by a session bean called Meeting Scheduler. That session bean calls three entity beans: Activity, User, and Room. Those beans and the container talk to the database.