获取当前登录用户IP(web)

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此方法采用的 HttpServletRequest 获取，故使用web项目，
说明，当存在使用 虚拟机 的情况，会导致获取的IP为 以太网适配器 的IP

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Arrays;

/**
 * @ClassName: IpUtil
 * @Description: 获取当前登录用户IP
 * @Author: Demon
 */
public class IpUtil {

    private static final String[] LOCAL_IP = {"127.0.0.1","localhost","0:0:0:0:0:0:0:1"};
    private static final String UNKNOWN = "unknown";

    public static String getIpAddr(HttpServletRequest request) {
        String ipAddress;
        try {
            ipAddress = request.getHeader("x-forwarded-for");
            if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("WL-Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getRemoteAddr();
                if (Arrays.asList(LOCAL_IP).contains(ipAddress)) {
                    // 根据网卡取本机配置的IP
                    InetAddress inet = null;
                    try {
                        inet = InetAddress.getLocalHost();
                    } catch (UnknownHostException e) {
                        e.printStackTrace();
                    }
                    assert inet != null;
                    ipAddress = inet.getHostAddress();
                }
            }
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            // "***.***.***.***".length()
            if (ipAddress != null && ipAddress.length() > 15) {
                // = 15
                if (ipAddress.indexOf(",") > 0) {
                    ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
                }
            }
        } catch (Exception e) {
            ipAddress = "";
        }
        return ipAddress;
    }


    /**
     * 判断IP地址的合法性，这里采用了正则表达式的方法来判断
     * return true，合法
     * */
    public static boolean ipCheck(String text) {
        if (text != null && !text.isEmpty()) {
            // 定义正则表达式
            String regex = "^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\."+
            "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."+
            "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."+
            "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$";
            // 判断ip地址是否与正则表达式匹配
            // 返回判断信息
            // 返回判断信息
            return text.matches(regex);
        }
        return false;
    }

}