Java根據request獲取客戶端IP+根據IP獲取Mac地址+獲取服務端IP

1. 獲取客戶端IP

    public String getIpAddr(HttpServletRequest request) {
        String ipAddress = null;
        ipAddress = request.getHeader("x-forwarded-for");
        if (ipAddress == null || ipAddress.length() == 0
                || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0
                || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0
                || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getRemoteAddr();
        }
        if (ipAddress != null && ipAddress.length() > 15) { 
            if (ipAddress.indexOf(",") > 0) {
                ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
            }
        }
        return ipAddress;
    }

2. 根據IP地址獲取Mac地址

使用cmd命令，適用於Windows服務器

    public String getMac(String ip) throws UnknownHostException, SocketException {
        String macAddress = "";
        String line;
        // 如果爲127.0.0.1,則獲取本地MAC地址
        if ("127.0.0.1".equals(ip) || "0:0:0:0:0:0:0:1".equals(ip) || "localhost".equals(ip) || getLocalIp().equals(ip)) {    //注意getLocalIp().equals(ip)，由於else中的方法獲取不到本機ip對應的的mac，所以放到這裏，調用的getLocalIp()
            InetAddress inetAddress = InetAddress.getLocalHost();
            byte[] mac = NetworkInterface.getByInetAddress(inetAddress)
                    .getHardwareAddress();
            // 下面代碼是把mac地址拼裝成String
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < mac.length; i++) {
                if (i != 0) {
                    sb.append("-");
                }
                // mac[i] & 0xFF 是爲了把byte轉化爲正整數
                String s = Integer.toHexString(mac[i] & 0xFF);
                sb.append(s.length() == 1 ? 0 + s : s);
            }
            // 把字符串所有小寫字母改爲大寫成爲正規的mac地址並返回
            macAddress = sb.toString().trim().toUpperCase();
            return macAddress;
        } else {    // 獲取非本地IP的MAC地址

//            //由於我測試的時候，使用"nbtstat -A " + ip獲取不到一些Mac，
//            //所以換成"arp -A " + ip
//            final String MAC_ADDRESS_PREFIX = "MAC Address = ";
//            try {
//                Process p = Runtime.getRuntime().exec("nbtstat -A " + ip);
//                InputStreamReader isr = new InputStreamReader(p.getInputStream());
//                BufferedReader br = new BufferedReader(isr);
//                while ((line = br.readLine()) != null) {
//                    if (line != null) {
//                        int index = line.indexOf(MAC_ADDRESS_PREFIX);
//                        if (index != -1) {
//                            macAddress = line.substring(index + MAC_ADDRESS_PREFIX.length()).trim().toUpperCase();
//                        }
//                    }
//                }
//                br.close();
//            } catch (IOException e) {
//                e.printStackTrace(System.out);
//            }

            try {
                Process p = Runtime.getRuntime().exec("arp -A " + ip);
                InputStreamReader isr = new InputStreamReader(p.getInputStream());
                BufferedReader br = new BufferedReader(isr);
                while ((line = br.readLine()) != null) {
                    if (line != null) {
                        int index = line.indexOf(ip);
                        if (index != -1) {
                            macAddress = line.substring(index + ip.length() + 10,index + ip.length() + 27).trim().toUpperCase();
                        }
                    }
                }
                br.close();
            } catch (IOException e) {
                e.printStackTrace(System.out);
            }
            return macAddress;
        }
    }

3. 獲取服務器IP

    public String getLocalIp() {
        try {
            Enumeration allNetInterfaces = NetworkInterface.getNetworkInterfaces();
            InetAddress ip;
            while (allNetInterfaces.hasMoreElements()){
                NetworkInterface netInterface = (NetworkInterface) allNetInterfaces.nextElement();
                Enumeration addresses = netInterface.getInetAddresses();
                while (addresses.hasMoreElements()){
                    ip = (InetAddress) addresses.nextElement();
                    if (ip != null && ip instanceof Inet4Address && !"127.0.0.1".equals(ip.getHostAddress())){
                        return  ip.getHostAddress();
                    }
                }
            }
        } catch (Exception e) {}
        return null;
    }