org.apache.commons.lang3.StringUtils.jar

java获取客户端ip（经过多次代理）提示StringUtils cannot be resolved
需要先 import org.apache.commons.lang3.StringUtils;
/* 内含 common-lang3.jar commons-lang3-3.9-bin.zip commons-lang3-3.9-src.zip 使用说明.txt*/
public static String getClientIp(HttpServletRequest request) {
String ip = request.getHeader("X-Forwarded-For");
if (!StringUtils.isEmpty(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.isEmpty(ip) && !"unKnown".equalsIgnoreCase(ip)) {
return ip;
}
return request.getRemoteAddr();

    }