import com.alibaba.druid.util.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.http.HttpServletRequest;

/**
 * IP地址
 */
public class IPUtils {
    private static Logger LOGGER = LoggerFactory.getLogger(IPUtils.class);

    /**
     * 獲取IP地址
     * <p>
     
 
* 使用Nginx等反向代理軟體， 則不能通過request.getRemoteAddr()獲取IP地址
     * 如果使用了多級反向代理的話，X-Forwarded-For的值並不止一個，而是一串IP地址，X-Forwarded-For中第一個非unknown的有效IP字串，則為真實IP地址
     */
    public static String getIpAddr(HttpServletRequest request) {
        String ip = null;
        try {
            ip = request.getHeader("x-forwarded-for"
 
);
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                ip = request.getHeader("Proxy-Client-IP");
            }
            if (StringUtils.isEmpty(ip) || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                ip = request.getHeader("WL-Proxy-Client-IP"
 
);
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                ip = request.getHeader("HTTP_CLIENT_IP");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                ip = request.getHeader("HTTP_X_FORWARDED_FOR");
            }
            if (StringUtils.isEmpty(ip) || "unknown".equalsIgnoreCase(ip)) {
                ip = request.getRemoteAddr();
            }
        } catch (Exception e) {
            LOGGER.error("IPUtils ERROR ", e);
        }

//        //使用代理，則獲取第一個IP地址
//        if(StringUtils.isEmpty(ip) && ip.length() > 15) {
//       if(ip.indexOf(",") > 0) {
//          ip = ip.substring(0, ip.indexOf(","));
//       }
//    }

        return ip;
    }

}