获取访问者IP地址，防代理_获取访问者ip防劫持

public String getClientIP() {
 
HttpServletRequest request = ServletActionContext.getRequest();
 
String ip = request.getHeader("x-forwarded-for");
if (null == ip || 0 == ip.length() || "unknown".equalsIgnoreCase(ip)) {
ip = request.getHeader("Proxy-Client-IP");
}
if (null == ip || 0 == ip.length() || "unknown".equalsIgnoreCase(ip)) {
ip = request.getHeader("WL-Proxy-Client-IP");
}
if (null == ip || 0 == ip.length() || "unknown".equalsIgnoreCase(ip)) {
ip = request.getHeader("X-Real-IP");
}
if (null == ip || 0 == ip.length() || "unknown".equalsIgnoreCase(ip)) {
ip = request.getRemoteAddr();
}
 
return ip;
}