using jnetpcap in java

i m developing with java an application which capture packet from a specific network Interface using the jnetpcap library then show informations such as : ip@ , mac, open ports and operating system from packets that i captured

Its my first time to implement something like mvc ( design pattern) My problem is when i press on select_interface button the application stop ( its in views package v1 class) http://ift.tt/2lOG0CY Please help me