### Question:
Pcaps { public static String lookupDev() throws PcapNativeException { PcapErrbuf errbuf = new PcapErrbuf(); Pointer result = NativeMappings.pcap_lookupdev(errbuf); if (result == null || errbuf.length() != 0) { throw new PcapNativeException(errbuf.toString()); } return result.getWideString(0); } private  Pcaps(); static List<PcapNetworkInterface> findAllDevs(); static PcapNetworkInterface getDevByAddress(
    InetAddress addr
  ); static PcapNetworkInterface getDevByName(
    String name
  ); static String lookupDev(); static Inet4NetworkAddress lookupNet(
    String devName
  ); static PcapHandle openOffline(
    String filePath
  ); static PcapHandle openOffline(
    String filePath, TimestampPrecision precision
  ); static PcapHandle openDead(
    DataLinkType dlt, int snaplen
  ); static PcapHandle openDead(
    DataLinkType dlt, int snaplen, TimestampPrecision precision
  ); static BpfProgram compileFilter(
    int snaplen, DataLinkType dlt, String bpfExpression,
    BpfCompileMode mode, Inet4Address netmask
  ); static DataLinkType dataLinkNameToVal(
    String name
  ); static String dataLinkTypeToName(
    DataLinkType dlt
  ); static String dataLinkValToName(
    int dataLinkVal
  ); static String dataLinkTypeToDescription(
    DataLinkType dlt
  ); static String dataLinkValToDescription(
    int dataLinkVal
  ); static String strError(int error); static String libVersion(); static String toBpfString(InetAddress inetAddr); static String toBpfString(MacAddress macAddr);  }### Answer:
@Test public void testLookupDev() throws Exception { String dev; try { dev = Pcaps.lookupDev(); } catch (PcapNativeException e) { logger.info("Pcaps.lookupDev() said {}", e.getMessage()); return; } assertNotNull(dev); assertTrue(dev.length() != 0); }