How can I get the IP address from a ServletRequest, not a HTTPServletRequest ?

Question

I'm trying to find a Java method that would get a ServletRequest and finds the IP address for that request. Something like this method that I found but would receive a ServletRequest instead of HTTPServletRequest :

Answer 1

I'd check if the request is an HTTP request, if so, use the method proposed in the other question. Otherwise, I'd trust the method getRemoteAddr() blindly.

if (request instanceof HTTPServletRequest) {
    HTTPServletRequest httpRequest = (HTTPServletRequest) request;
    // read X-Forwarded-For header, etc. etc.
} else {
    ip = request.getRemoteAddr();
}

Answer 2

The ServletRequest also provides the method java.lang.String getRemoteAddr() see https://docs.oracle.com/javaee/6/api/javax/servlet/ServletRequest.html#getRemoteAddr() for more details.