How to get client Ip Address in Java

How to get client Ip Address in Java

Normally, you can use servletRequest.getRemoteAddr() to get the client's IP address that's accessing your Java web application.

String ipAddress = request.getRemoteAddr();    

But, if user is behind a proxy server or access your web server through a load balancer (for example, in cloud hosting), the above code will get the IP address of the proxy server or load balancer server, not the original IP address of a client.

To solve it, you should get the IP address of the request's HTTP header "X-Forwarded-For (XFF)".

   //is client behind something?     String ipAddress = request.getHeader("X-FORWARDED-FOR");       if (ipAddress == null) {    	   ipAddress = request.getRemoteAddr();       }

Read full article from How to get client Ip Address in Java