java 获取mac地址

   一下是用java来获取mac地址，一般可用作接口权限控制

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;

public class UdpGetClientMacAddr {
	private String sRemoteAddr;
	private int iRemotePort = 137;
	private byte[] buffer = new byte[1024];
	private DatagramSocket ds = null;

	public static void main(String[] args) {
		try {
                       //要获取的机器mac地址的ip
			UdpGetClientMacAddr mac = new UdpGetClientMacAddr("192.168.2.176");
			String ma = mac.GetRemoteMacAddr();
			System.out.println(ma);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	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 = 15; i < 45; 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 {

		int i = brevdata[56] * 18 + 56;
		String sAddr = "";
		StringBuffer sb = new StringBuffer(17);

		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;
	}
}