java - maven项目读不到log4j的配置文件

我建立了一个demo项目,目录结构如下:

类的代码:

package com.asiainfo.firstmaven.helloworld;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class HelloWorld {
    String sayHello() {
        return "Hello World";
    }

    public static void main(String[] args) {
        Logger logger = LogManager.getLogger(HelloWorld.class);
        logger.debug("I am a debug");
        logger.error("I am a error");
        logger.warn("I am a warn");
        logger.info("I am a info");

        System.out.println(new HelloWorld().sayHello());
    }
}        

运行总是报错:

ERROR StatusLogger No log4j2 configuration file found. Using default configuration: logging only errors to the console.

是哪里还需要配置吗? 跪求解答..