避开nginx获取客户端真实IP的方式

package com.niwodai.credit.loanswap.util;

import javax.servlet.http.HttpServletRequest;

public class GetIPUtil {

	public static String getIpAddr(HttpServletRequest request) {
		String ip = request.getHeader("x-forwarded-for");
		
		String ip2=request.getHeader("X-Forwarded-For");
		if (ip2!=null && (!"unknown".equalsIgnoreCase(ip2))) {
			ip = ip2;
		}
		
		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();
		}
		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");
		}
		// 如果是多级代理，那么取第一个ip为客户ip
		if (ip != null && ip.indexOf(",") != -1) {
			ip = ip.substring(ip.lastIndexOf(",") + 1, ip.length()).trim();
		}
		return ip;
	}

}