title: c3p0: what does `maxIdleTime` really mean?
body: <p>in c3p0, maxIdleTime means:</p>
  
  <p><em>maxIdleTime: (Default: 0) Seconds a Connection can remain pooled but unused before being discarded. Zero means idle connections never expire.</em></p>
  
  <p>I don't get it. Let's say, if there are 10 awaiting connections in the connection pool, and after maxIdleTime has passed, there are still no new database requests, then all these connections should be discarded? then there will be 0 awaiting connections in the pool? </p>