1. public static String getIpAddr(HttpServletRequest request){
    2.     if (request == null){
    3.         return "unknown";
    4.     }
    5.     String ip = request.getHeader("x-forwarded-for");
    6.     if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)){
    7.         ip = request.getHeader("Proxy-Client-IP");
    8.     }
    9.     if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)){
    10.         ip = request.getHeader("X-Forwarded-For");
    11.     }
    12.     if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)){
    13.         ip = request.getHeader("WL-Proxy-Client-IP");
    14.     }
    15.     if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)){
    16.         ip = request.getHeader("X-Real-IP");
    17.     }
    19.     if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)){
    20.         ip = request.getRemoteAddr();
    21.     }
    22.     return "0:0:0:0:0:0:0:1".equals(ip) ? "127.0.0.1" : ip;
    23. }