JSP Get customer service MAC address __jsp

Package com.sun.servlet;
Import java.io.IOException;
Import Java.net.DatagramPacket;
Import Java.net.DatagramSocket;
Import java.net.InetAddress;
 /** * Host A sends a "UDP-NETBIOS-NS" query packet to Host B, that is, to host B's 137 port and sends a query packet to ask Host B's NetBIOS names information. * Second, Host B receives the "Udp-netbios-ns" query package, assuming Host B correctly installs the NetBIOS service ...
 And the 137 port is open, Host B sends a "UDP-NETBIOS-NS" reply packet to host A, that is, send answer package to host a. * and using UDP (NetBIOS Name Service) To quickly obtain a remote host MAC address * * @author windy/public class Udpgetclientmacaddr {private Strin
	G Sremoteaddr;
	private int iremoteport=137;
	Private byte[] buffer = new byte[1024];

	Private Datagramsocket Ds=null;
		Public udpgetclientmacaddr (String straddr) throws exception{sremoteaddr = straddr;
	ds = new Datagramsocket (); } Protected final Datagrampacket send (final byte[] bytes) throws IOException {Datagrampacket dp = new Datagrampacket (
		Bytes,bytes.length,inetaddress.getbyname (SREMOTEADDR), iremoteport);
		Ds.send (DP);
	return DP; } protected final Datagrampacket receive () throws Exception {DatagramPacket DP = new Datagrampacket (buffer,buffer.length);
		Ds.receive (DP);
	return DP;
		} protected byte[] Getquerycmd () throws Exception {byte[] T_ns = new BYTE[50];
		T_ns[0] = 0x00;
		T_NS[1] = 0x00;
		T_NS[2] = 0x00;
		T_NS[3] = 0x10;
		T_NS[4] = 0x00;
		T_NS[5] = 0x01;
		T_NS[6] = 0x00;
		T_NS[7] = 0x00;
		T_NS[8] = 0x00;
		T_NS[9] = 0x00;
		T_NS[10] = 0x00;
		T_NS[11] = 0x00;
		T_NS[12] = 0x20;
		T_NS[13] = 0x43;

		T_NS[14] = 0x4b;
		for (int i =; I < i++) {t_ns[i] = 0x41;
		} t_ns[45] = 0x00;
		T_NS[46] = 0x00;
		T_NS[47] = 0x21;
		T_NS[48] = 0x00;
		T_NS[49] = 0x01;
	return T_ns;
		} Protected Final String getmacaddr (byte[] brevdata) throws Exception {//Get computer name int i = brevdata[56] * 18 + 56;
		String saddr= "";
		StringBuffer sb = new StringBuffer (17); Read the number of Names (NetBIOS names, each of which is 18 bytes per NetBIOS Names)//And then calculate the position of the "Unit ID" field from the 56th byte position =56+number of NAMESX1
		8, and finally from this location to read a continuous 6 bytes, is the destination host's MAC address. for (int j = 1; J < 7;j++) {saddr = inteGer.tohexstring (0xFF & Brevdata[i+j]);
			if (Saddr.length () < 2) {sb.append (0);
			} sb.append (Saddr.touppercase ());
		if (J < 6) sb.append (': ');
	return sb.tostring ();
		Public final void Close () {try {ds.close ();
		catch (Exception ex) {ex.printstacktrace ();
		} Public final String getremotemacaddr () throws Exception {byte[] bqcmd = Getquerycmd ();
		Send (Bqcmd);
		Datagrampacket DP = receive ();
		String SMAC = getmacaddr (Dp.getdata ());

		Close ();
	return SMAC; }
}

Jsp:

<span style= "color: #000000;" ><%
				String smac = "";
				String sip = Request.getheader ("x-forwarded-for");
				if (sip = = NULL | | sip.length () = 0
						| | "Unknown". Equalsignorecase (SIP)) {
					sip = Request.getheader ("Proxy-client-ip");
				}
				if (sip = = NULL | | sip.length () = 0
						| | "Unknown". Equalsignorecase (SIP)) {
					sip = Request.getheader ("Wl-proxy-client-ip");
				}
				if (sip = = NULL | | sip.length () = 0
						| | "Unknown". Equalsignorecase (SIP)) {
					sip = request.getremoteaddr ();
				}
				Udpgetclientmacaddr Umac = new udpgetclientmacaddr (SIP);
				SMAC = Umac. Getremotemacaddr ();
				Session.setattribute ("Smac", SMAC);
			%></span>