how to use jpcap?

i have installed jpcap and add it in library but i have error in this line:

 String[] devices = JpcapCaptor.getDeviceList();

i think I added it wrong because it said: Javadoc not found. Either Javadoc documentation for this item does not exist or you have not added specified Javadoc in the Java Platform Manager or the Library Manager.

 public static void main(String[] args) throws UnknownHostException {
        /开发者_如何学Python/ TODO code application logic here
      String[] devices = JpcapCaptor.getDeviceList();
        if(args.length<1){
            System.out.println("Usage: java SentUDP <device index (e.g., 0, 1..)>");
            for(int i=0;i<devices.length;i++)
                System.out.println(i+":"+devices[i].name+"("+devices[i].description+")");
            System.exit(0);
        }

See how-to-add-jcap-jar-and-its-javadoc-into-netbeans. It may answer you question.