public static String getMACAddress(){   
        String address = "";   
        String os = System.getProperty("os.name");   
        String osUser=System.getProperty("user.name");   
        if (os != null && os.startsWith("Windows")) {    
           try {    
                String command = "cmd.exe /c ipconfig /all";                   
                Process p = Runtime.getRuntime().exec(command);    
                BufferedReader br =new BufferedReader(new InputStreamReader(p.getInputStream()));   
                String line;   
                while ((line = br.readLine()) != null) {     
                    if (line.indexOf("Physical Address") > 0) {   
                        int index = line.indexOf(":");   
                        index += 2;   
                        address = line.substring(index);   
                        break;   
                    }
                    if (line.indexOf("Default Gateway") > 0) {   
                        int index = line.indexOf(":");   
                        index += 2;   
                        address = line.substring(index);   
                        break;   
                    }
                }    
                br.close();   
                return address.trim();   
            }   
            catch (IOException e) {   
            }   
        }   
        return address;   
    }