1. 您需要下载此二进制存档

添加log4j-api-2.8。 1.jar和log4j-core-2.8.1.jar到你的项目。 （在NetBeans中：文件 - >项目属性 - >库。我必须将它添加到编译和运行，否则我会在运行时收到错误。）

Add "log4j-api-2.8.1.jar" and "log4j-core-2.8.1.jar" to your project. (in NetBeans: File -> Project Properties -> Libraries. I had to add it to both "compile" and "run", or else I would get an error at runtime.)

告诉Log4j文件所在的位置。 （在NetBeans中：文件 - >项目属性 - >运行。粘贴

Tell Log4j where the file is. (in NetBeans: File -> Project Properties -> Run. Paste

-Dlog4j.configurationFile=/path/to/your/file/log4j2.xml 

进入Textfield VM-Options

into the Textfield "VM-Options"

1. 在指定路径创建名为log4j2.xml的XML（我在我的项目的主文件夹）与您的配置，例如

1. Create an XML called log4j2.xml at the specified path (I did it in the main folder of my project) with your configuration, e.g.

<?xml version="1.0" encoding="UTF-8"?>

<Configuration status="warn">
  <Appenders>
    <Console name="STDOUT" target="SYSTEM_OUT">
      <PatternLayout pattern="%m%n"/>
    </Console>
    <File name="FILE" fileName="logs/myLog.log">
      <PatternLayout>
        <Pattern>%d %p %c{1.} [%t] %m%n</Pattern>
      </PatternLayout>
    </File>
  </Appenders>
  <Loggers>
    <Root level="INFO">
      <AppenderRef ref="FILE" level="INFO"/>
      <AppenderRef ref="STDOUT" level="ERROR"/>
    </Root>
  </Loggers>
</Configuration>

这会创建两个appender，一个ConsoleAppender和一个FileAppender，它们登录System.out并调用一个文件分别是myLog.log。级别INFO和更高级别的日志消息将记录到文件中，只会将错误打印到控制台。

This creates two appenders, a ConsoleAppender and a FileAppender, that log into System.out and a file called "myLog.log", respectively. Log messages of level INFO and higher are logged into the file, only errors are printed to the console.

这是一些示例代码，用于演示如何使用Log4j2：

This is some sample code to demonstrate how Log4j2 is used:

import java.io.IOException;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

public class Demo {

    private final static Logger log = LogManager.getLogger(Demo.class);

    public static void main(String[] args) throws IOException {
        log.info("starting...");
        try {
            ((Object) null).toString();
        } catch (Exception e) {
            log.error("error message");
        }
        log.info("some info.");
    }
}

运行此导致控制台输出

    error message

虽然该文件包含

    2017-03-29 14:37:20,675 INFO l.Demo [main] starting...
    2017-03-29 14:37:20,676 ERROR l.Demo [main] error message
    2017-03-29 14:37:20,676 INFO l.Demo [main] some info.

我希望这给你省点麻烦，因为我花了很长时间来解决这个问题。随意编辑这篇文章 - 我不知道我的陈述有多正确，这些只是对我有用的步骤。

I hope this saved you some trouble, as it took me quite some time to figure this out. Feel free to edit this post - I have no idea how correct my statements are, these are just the steps that worked for me.