All enterprise bean container-managed persistence (CMP) beans under the EJB 2.x specification receive a standard EJB exception when an operation fails.
JDBC applications receive a standard SQL exception if any JDBC operation fails.
The product provides special exceptions for its relational resource adapter (RRA),
to indicate that the connection currently held is no longer valid. The
ConnectionWaitTimeout exception indicates that the application timed out trying to get a connection. The StaleConnection exception indicates that the connection is no longer valid.