code: public synchronized boolean killConnectionListener(String id)
     {
        ConnectionListener cl = null;
        Iterator<ConnectionListener> it = listeners.keySet().iterator();
        while (cl == null && it.hasNext())
        {
           ConnectionListener l = it.next();
           if (Integer.toHexString(System.identityHashCode(l)).equals(id))
              cl = l;
        }
  
        if (cl != null)
        {
           try
           {
              pool.returnConnectionListener(cl, true);
           }
           catch (Exception e)
           {
              log.tracef(e, "killConnectionListener(%s)", id);
           }
  
           return true;
        }
        
        return false;
     }
docs: {@inheritDoc}