工具集-Java獲取客戶端的 IP

廢話不多說，直接上代碼，這裏主要是寫一下主要方法：

public static String getIP(HttpServletRequest request) {

        String ip = request.getHeader("X-Real-IP");

        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("x-forwarded-for");
        } else {
            return ip;
        }

        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        } else {
            // 當有多級反向代理時，x-forwarded-for值爲多個時取第一個ip地址
            if (ip.indexOf(IP_SEPARATOR) != -1) {
                ip = ip.substring(0, ip.indexOf(IP_SEPARATOR));
            }
            return ip;
        }

        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        } else {
            return ip;
        }

        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        } else {
            return ip;
        }

        if (StringUtils.isBlank(ip) || "unknown".equalsIgnoreCase(ip)) {
            ip = "";
        }
        return ip;
    }