I cannot tell just from this information with certainty, but it appears that you are attempting to inject a DBCP Connection into the Managed Bean and it looks like the Connection factory could not provide a valid Connection object. Most likely, either it attempted to create a new Connection and failed, or it attempted to pull an existing Connection that was broken - which usually happens when the Connection's network linkage times out.
If the connection has timed out, you need to add some extra directives to your
Tomcat Connection Pool definition to ensure that the Pool Manager discards old broken Connections or keeps them alive. The exact directives required for this vary depending on the database, so read the Tomcat documentation.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.