@Test
    public void nullIPsandMacsReturnNull() {
        assertNull(ARPInfo.getMACFromIPAddress(null));
        assertNull(ARPInfo.getIPAddressFromMAC(null));
    }
To work on unit tests, switch the Test Artifact in the Build Variants view.
library/src/test/java/com/stealthcopter/networktools/ARPInfoTest.java