SessionStateListener onMissedHeartBeat(), onHeartBeatTimeout() is called once network connection reestablishes after a disconnect

I need to implement the SessionStateListener in the Initiator to understand when there is a network disconnect event.

Firstly, I defined my Initiator to Implement SessionStateListener, Then I added the listener by:

Session.lookupSession(quickfixSessionID).addStateListener(fixInitiator);

and now trying to receive following callbacks to check if the network is down:
@Override
public void onMissedHeartBeat()

{ System.out.println("######onMissedHeartBeat"); }

@Override
public void onHeartBeatTimeout()

{ System.out.println("######Heartbeat time out"); }

But the onMissedHeartBeat() and OnHeartbeatTimeout() methods are called only once the network connection is reestablished. I need to understand when the network went down and when it came back.

Please send me if you have any solution for the above to [email protected]