I have written a web app that uses Spring MVC libraries and Spring JDBC to connect to an Oracle DB. (I don't use any ORM type libraries as I create stored procedures on Oracle that do my stuff and I'm quite happy with that.) I use a connection pool to Oracle managed by the Tomcat container The app generally works absolutely fine by the way! BUT... I noticed the other day when I tried to set up the app on another Tomcat instance that I had forgotten to configure the connection pool and obviously the app could not get hold of an org.apache.commons.dbcp.BasicDataSource object, so it crashed. I define the pool params in the tomcat "context.conf" In my "web.xml" I have: <servlet> <servlet-name>appServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/Spring/appServlet/servlet-context.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>appServlet</servlet-name> <!-- Map *everything* to appServlet --> <url-pattern>/</url-pattern> </servlet-mapping> <resource-ref> <description>Oracle Datasource example</description> <res-ref-name>jdbc/ora1</res-ref-name> <res-type>org.apache.commons.dbcp.BasicDataSource</res-type> <res-auth>Container</res-auth> </resource-ref> And I have a Spring "servlet-context.xml" where JNDI is used to map the data source object provided by the connection pool to a Spring bean with the ID of "dataSource": <jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/ora1" resource-ref="true" /> Here's the question: Where do I trap the case where the database cannot be accessed for whatever reason? I don't want the user to see a yard-and-a-half of Java stack trace in their browser, rather a nicer message that tells them there is a database problem etc. It seems that my app tries to configure the "dataSource" bean (in "servlet-context.xml") before any code has tested it can actually provide a dataSource object from the pool?! Maybe I'm not fully understanding exactly what is going on in these stages of the app firing up ... Thanks for any advice!