Obtain IP Address from client's HTTP Request using Java

Question

Am using Spring 4 MVC for RESTful Web Services on Tomcat 7.

Was wondering if an external client sends a HTTP request, is there a way to obtain the particular client's IP Address within the server side layer?

https://stackoverflow.com/questions/22877350/how-to-extract-ip-address-in-spring-mvc-controller-get-call — bkis, Oct 06 '17 at 18:08
@Chrylis - Why should I be aware of the X-Forwarded-For header? Thanks for the precautionary head's up. — PacificNW_Lover, Oct 06 '17 at 18:13
Because if you're behind a firewall or load balancer (the usual case), the IP address you get from the HTTP connection won't be the client's. — chrylis -cautiouslyoptimistic-, Oct 06 '17 at 22:09
@PacificNW_Lover could you close this question by accepting an answer? if you don't it will remain open and people will think you still need help. — Victor, Oct 08 '17 at 14:00

Yuriy Bochkarev · Answer 1 · 2017-10-06T18:33:16.717

org.springframework.security.web.authentication.WebAuthenticationDetails

A holder of selected HTTP details related to a web authentication request.

Indicates the TCP/IP address the authentication request was received from.

String ipAddress = ((WebAuthenticationDetails)SecurityContextHolder.getContext().getAuthentication().getDetails()).getRemoteAddress();

If you are testing on a local application, your ip address will be "0:0:0:0:0:0:0:1"

score 1 · Answer 2 · answered Oct 06 '17 at 18:14

Simple POJO

public static InetAddress getClientIpAddr(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.getHeader("HTTP_CLIENT_IP");  
    }  
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {  
        ip = request.getHeader("HTTP_X_FORWARDED_FOR");  
    }  
    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {  
        ip = request.getRemoteAddr();  
    }  
    try {
        return InetAddress.getByName(ip);
    } catch (UnknownHostException e) {
        return null;
    }  
}

please specify `UnknownHostException`, rmi or net ? – Rajat Mar 16 '20 at 07:42 — Rajat, Mar 16 '20 at 07:42

Obtain IP Address from client's HTTP Request using Java

2 Answers2