Java獲取客戶端真實IP地址

Java代碼

import javax.servlet.http.HttpServletRequest;  
  
/** 
 * 獲取對象的IP地址等信息 */  
public class IPUtil {  
  
    /** 
     * 獲取用戶真實IP地址，不使用request.getRemoteAddr();的原因是有可能用戶使用了代理軟件方式避免真實IP地址, 
     * 可是，如果通過了多級反向代理的話，X-Forwarded-For的值並不止一個，而是一串IP值，究竟哪個才是真正的用戶端的真實IP呢？ 
     * 答案是取X-Forwarded-For中第一個非unknown的有效IP字符串。 
     * 如：X-Forwarded-For：192.168.1.110, 192.168.1.120, 192.168.1.130, 
     * 192.168.1.100 
     * 用戶真實IP為： 192.168.1.110 
     * @param request 
     * @return 
     */  
    public static String getIpAddress(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;  
    }  
      
}

參考:

https://www.cnblogs.com/chenglc/p/6856734.html