title: Tomcat complains about a thread not being stopped
body: <p>I'm getting exceptions about threads being started and not ending or being stopped. The WebappClassLoader complains that these threads will cause a memory leak.</p>
  
  <p>What is happening here?</p>
  
  <ol>
  <li>Is it likely such threads will cause a memory leak? Or just possible?</li>
  <li>Is Catalina being overly sensitive?</li>
  <li>Is this even a valid programming technique?</li>
  </ol>
  
  <p>(Managing this aspect of a Tomcat application is new to me. But I have to learn it as the webapp is running out of database connections under high load and this needs to be solved. Searching for memory leaks is one of a number of things we're looking into.)</p>