java中如何实现取得机器的网卡物理地址

Question

  private String getMacAddress(String remotePcIP){
      String str="";
      String macAddress="";
      try {
           Process pp= Runtime.getRuntime().exec ("nbtstat -A " + remotePcIP);
           InputStreamReader ir = new InputStreamReader(pp.getInputStream());
           LineNumberReader input = new LineNumberReader (ir);
           for (int i = 1; i <100; i++)
              {
               str=input.readLine();
               if (str!=null)
                 {
                   if(str.indexOf("MAC Address")>1)
                     { macAddress=str.substring(str.indexOf("MAC Address")+14,str.length());
                       break;
                    }
                 }
              }
          }
      catch (IOException ex) {}
      return macAddress;
  }