Special Edition Using Enterprise JavaBeans™ 2.0

System Exceptions

Any exception condition or error that isn’t an application exception is a system exception. This means that system exceptions are instances of RuntimeException, RemoteException, Error, and their subclasses. These exceptions report unexpected low-level problems that aren’t related to the application logic. Problems such as an inability to communicate with another EJB or an error obtaining a database connection are reported using system exceptions.

Other than RemoteException and its subclasses, system exceptions are unchecked exceptions, so you’re not expected to catch the majority of them. As you were reminded earlier, an unchecked exception represents a problem that either shouldn’t happen in a correct program or is severe ...