获取访问者ip

// 获取访问者ip   
    public static String getIpAddr(HttpServletRequest request) {   
        String ip = request.getHeader("x-forwarded-for");   
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {   
            ip = request.getHeader("Proxy-Client-IP");   
        }   
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {   
            ip = request.getHeader("WL-Proxy-Client-IP");   
        }   
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {   
            ip = request.getRemoteAddr();   
        }   
        return ip;   
    }