Log4j2 구성-log4j2 구성 파일을 찾을 수 없습니다.

Log4j2 구성-log4j2 구성 파일을 찾을 수 없습니다.

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최근에 저는 log4j2 로거를 사용하는 방법을 배우기로 결정했습니다. 필요한 jar 파일을 다운로드하고 라이브러리, xml 구성 파일을 생성하여 사용해 보았습니다. 불행히도 콘솔 (Eclipse) 에서이 진술을 얻습니다.

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

이것은 내 테스트 클래스 코드입니다.

package log4j.test;

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

public class Log4jTest
{
    static final Logger logger = LogManager.getLogger(Logger.class.getName());

    public static void main(String[] args) {    
        logger.trace("trace");
        logger.debug("debug");
        logger.info("info");
        logger.warn("warn");
        logger.error("error");
        logger.fatal("fatal");
    }
}

그리고 내 xml 구성 파일 :

<?xml version="1.0" encoding="UTF-8"?>
<Configuration package="log4j.test" 
               status="WARN">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
        </Console>
    </Appenders>
    <Loggers>
        <Logger name="log4j.test.Log4jTest" level="trace">
            <AppenderRef ref="Console"/>
        </Logger>
        <Root level="trace">
            <AppenderRef ref="Console"/>
        </Root>
    </Loggers>
</Configuration>

<Logger>태그가 없는 xml , 패키지 사양 및 다양한 폴더 / 패키지 디렉토리에서도 시도했지만 도움이되지 않았습니다. 이제 내 log4j2.xml파일은 Eclipse의 프로젝트 폴더에 직접 있습니다.

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이것은 maven 등이없는 간단한 일식 자바 프로젝트입니까? 이 경우 클래스 경로에서 log4j2.xml파일 src을 찾을 수 있도록 폴더 아래 에 파일 을 넣어야합니다 . maven을 사용하는 경우 아래에 src/main/resources놓거나src/test/resources

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다음 솔루션 중 하나를 선택해야합니다.

1. Put the log4j2.xml file in resource directory in your project so the log4j will locate files under class path.
2. Use system property -Dlog4j.configurationFile=file:/path/to/file/log4j2.xml

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Was following the documentations - Apache Log4j2 Configuratoin and Apache Log4j2 Maven in configuring log4j2 with yaml. As per the documentation, the following maven dependencies are required:

  <dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-api</artifactId>
    <version>2.8.1</version>
  </dependency>
  <dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-core</artifactId>
    <version>2.8.1</version>
  </dependency>

and

<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-yaml</artifactId>
    <version>2.8.6</version>
</dependency>

Just adding these didn't pick the configuration and always gave error. The way of debugging configuration by adding -Dorg.apache.logging.log4j.simplelog.StatusLogger.level=TRACE helped in seeing the logs. Later had to download the source using Maven and debugging helped in understanding the depended classes of log4j2. They are listed in org.apache.logging.log4j.core.config.yaml.YamlConfigurationFactory:

com.fasterxml.jackson.databind.ObjectMapper
com.fasterxml.jackson.databind.JsonNode
com.fasterxml.jackson.core.JsonParser
com.fasterxml.jackson.dataformat.yaml.YAMLFactory

Adding dependency mapping for jackson-dataformat-yaml will not have the first two classes. Hence, add the jackson-databind dependency to get yaml configuration working:

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.8.6</version>
</dependency>

You may add the version by referring to the Test Dependencies section of log4j-api version item from MVN Repository. E.g. for 2.8.1 version of log4j-api, refer this link and locate the jackson-databind version.

Moreover, you can use the below Java code to check if the classes are available in the classpath:

System.out.println(ClassLoader.getSystemResource("log4j2.yml")); //Check if file is available in CP
ClassLoader cl = Thread.currentThread().getContextClassLoader(); //Code as in log4j2 API. Version: 2.8.1
 String [] classes = {"com.fasterxml.jackson.databind.ObjectMapper",
 "com.fasterxml.jackson.databind.JsonNode",
 "com.fasterxml.jackson.core.JsonParser",
 "com.fasterxml.jackson.dataformat.yaml.YAMLFactory"};

 for(String className : classes) {
     cl.loadClass(className);
 }

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Eclipse will never see a file until you force a refresh of the IDE. Its a feature! So you can put the file all over the project and Eclipse will ignore it completely and throw these errors. Hit refresh in Eclipse project view and then it works.

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Additionally to what Tomasz W wrote, by starting your application you could use settings:

-Dorg.apache.logging.log4j.simplelog.StatusLogger.level=TRACE 

to get most of configuration problems.

For details see Log4j2 FAQ: How do I debug my configuration?

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In my case I had to put it in the bin folder of my project even the fact that my classpath is set to the src folder. I have no idea why, but it's worth a try.

참고URL : https://stackoverflow.com/questions/25487116/log4j2-configuration-no-log4j2-configuration-file-found