@Test(expected = IllegalArgumentException.class)
    public void testIllegalArgumentThrownOnInvalidMACaddress() {
        ARPInfo.getIPAddressFromMAC("00:00:00:xx");
    }
To work on unit tests, switch the Test Artifact in the Build Variants view.
library/src/test/java/com/stealthcopter/networktools/ARPInfoTest.java