onSubscription method

Event handler that is called by Lightstreamer to notify that a Subscription has been successfully subscribed to through the Server.

This can happen multiple times in the life of a Subscription instance, in case the Subscription is performed multiple times through LightstreamerClient.unsubscribe and LightstreamerClient.subscribe. This can also happen multiple times in case of automatic recovery after a connection restart.
This notification is always issued before the other ones related to the same subscription. It invalidates all data that has been received previously.
Note that two consecutive calls to this method are not possible, as before a second onSubscription event is fired an onUnsubscription event is eventually fired.
If the involved Subscription has a two-level behavior enabled (see Subscription.setCommandSecondLevelFields and Subscription.setCommandSecondLevelFieldSchema) , second-level subscriptions are not notified.