Checking Connection Pool Size

Is there a way I can check the status of the connection pool using JNDI?

I'm working on a web application using Tomcat and SQL Server with the JTDS driver and I'm having concerns that I may have some stray connections open or some performance issues that I want to tweak. I'd like to make a JSP/Servlet that I can get the health information (active connections, open connections etc) about the connection pool at any given time.

Any help on how to do such a thing?

Some pools or J2EE containers have the functionality built-in. Sometimes it is a config setting on the pool. Sometimes it is a JMX component exposing the runtime state of some kind of pool manager. I'd start by checking the documentation, admin gui, and any javadoc for stuff that sounds JMX-ish.

I looked into the JMX stuff and I've got Tomcat's manager app to at least display what I'm looking for.
I've been messing around with the query strings and came up with this one for now.
http://<server>/manager/jmxproxy/?qry=Catalina%3Atype%3DDataSource%2C*

Thanks.