获取请求主机IP地址,如果通过代理进来，则透过防火墙获取真实IP地址

/**
* 获取请求主机IP地址,如果通过代理进来，则透过防火墙获取真实IP地址;
* @Title: getIpAddress
* @Description: TODO(这里用一句话描述这个方法的作用)
* @param @param request
* @param @return
* @param @throws IOException    参数
* @return String    返回类型
* @throws
*/
public String getIpAddress(HttpServletRequest request) throws IOException {
// 获取请求主机IP地址,如果通过代理进来，则透过防火墙获取真实IP地址

String ip = request.getHeader("X-Forwarded-For");

if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
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();
}
} else if (ip.length() > 15) {
String[] ips = ip.split(",");
for (int index = 0; index < ips.length; index++) {
String strIp = (String) ips[index];
if (!("unknown".equalsIgnoreCase(strIp))) {
ip = strIp;
break;
}
}
}
return ip;
}