getItemGroup method
Inquiry method that can be used to read the item group specified for this MpnSubscription.
Note: if the MpnSubscription has been created by the client, such as when obtained through LightstreamerClient.getMpnSubscriptions, items are always expressed with an "Item Group"", even if originally the MPN subscription used an "Item List".
Lifecycle This method can only be called if the MpnSubscription has been initialized using an "Item Group"
Returns the "Item Group" to be subscribed to through the server, or null if the MpnSubscription was initialized with an "Item List" or was not initialized at all.
Implementation
external String? getItemGroup();