获取IP地址

package com.common.utils.util;
import javax.servlet.http.HttpServletRequest;
/**
 * 常用通用的公用方法
 *
 * @author Forever丶诺
 * @data 2019/5/16 19:18
 */
public class IpUtil {
    public IpUtil(){}
    /**
     * 获取 IP地址
     * 使用 Nginx等反向代理软件， 则不能通过 request.getRemoteAddr()获取 IP地址
     * 如果使用了多级反向代理的话，X-Forwarded-For的值并不止一个，而是一串IP地址，
     * X-Forwarded-For中第一个非 unknown的有效IP字符串，则为真实IP地址
     *
     * @param request
     * @return
     * @author Ms.WenJing
     */
    public static String getIpAddr(HttpServletRequest request) {
        String unknown = "unknown";
        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)) {
            // 若以上方式均为获取到ip则证明获得客户端并没有采用反向代理直接使用getRemoteAddr()获取客户端的ip地址
            ip = request.getRemoteAddr();
        }
        // 多个路由时，取第一个非unknown的ip
        final String[] arr = ip.split(",");
        for (final String str : arr) {
            if (!unknown.equalsIgnoreCase(str)) {
                ip = str;
                break;
            }
        }
        return ip;
    }
}