try with below code...
import javax.servlet.http.HttpServletRequest;
@GET
@Path("/yourservice")
@Produces("text/xml")
public void activate(@Context HttpServletRequest requestContext,@Context SecurityContext context){
String yourIP = requestContext.getRemoteAddr().toString();
//If security is enabled
Principal principal = context.getUserPrincipal();
String userName = principal.getName();
}