java 从request里面获取登入者ip

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();

}