You can get interface's MAC address directly from
PcapIf class by calling on
PcapIf.getHardwareAddress(). This method will return a byte containing the hardware address. The length of the array tells the exact length of the address. If null is returned, that means that the physical interface, does not support hardware addresses, such as loopback interface, a PPP interface, etc..
PcapIf.getHardwareAddress() method is a convenience method. The actual implementation of this method is in the
PcapUtils.getHardwareAdderess() call. Libpcap library does not provide any function calls to acquire a hardware address of an interface. This has been added as an extension to libpcap in a