第二种代码:
public static String getIp(HttpServletRequest request) {
String remoteAddr = request.getRemoteAddr();
String forwarded = request.getHeader("X-Forwarded-For");
String realIp = request.getHeader("X-Real-IP");
String ip = null;
if (realIp == null) {
if (forwarded == null) {
ip = remoteAddr;
} else {
ip = remoteAddr + "/" + forwarded;
}
} else {
if (realIp.equals(forwarded)) {
ip = realIp;
} else {
ip = realIp + "/" + forwarded.replaceAll("， " + realIp， "");
}
}
return ip;
}
　　第三种代码:
public static String getIp2(HttpServletRequest request) {
String ip = request.getHeader("X-Forwarded-For");
if(StringUtils.isNotEmpty(ip) && !"unKnown".equalsIgnoreCase(ip)){
//多次反向代理后会有多个ip值，第一个ip才是真实ip
int index = ip.indexOf("，");
if(index != -1){
return ip.substring(0，index);
}else{
return ip;
}
}
ip = request.getHeader("X-Real-IP");
if(StringUtils.isNotEmpty(ip) && !"unKnown".equalsIgnoreCase(ip)){
return ip;
}
return request.getRemoteAddr();
}
　　第三种是合适的，清晰理解的