/**
  * Checks whether this connection currently has an established and <em>active</em> session with
  * the peer.
  *
  * <p>An active session is one that can be used to exchange (application) data with the peer.
  *
  * @return <code>true</code> if an active session is established with the client
  */
 public boolean hasActiveEstablishedSession() {
   return establishedSession != null && establishedSession.isActive();
 }
 @Override
 public void sessionEstablished(Handshaker handshaker, DTLSSession establishedSession)
     throws HandshakeException {
   this.establishedSession = establishedSession;
   LOGGER.log(Level.FINE, "Session with [{0}] has been established", establishedSession.getPeer());
 }