客户端访问服务器获取用户ip

/**
 * 获取用户登录IP

 * 传入：request       输出：用户ip值

 */
public class IPUtil {
 public static String getIpAddr(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();  
     }  
     return ip;  
 }  

}