Java获取请求ip地址

    public String checkIpAddress(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.getRemoteAddr();   
      
      }   
      
      return ip;  
      
     }