找不到 log4j2 配置文件。 使用默认配置：仅将错误记录到控制台

Question

$ java -Dlog4j.configuration=file:///path/to/your/log4j2.xml -jar /path/to/your/jar_file.jar

Written to the console, you get

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

But, it also looks like the configuration file has been found and was not parsable:

    log4j:WARN Continuable parsing error 2 and column 31
    log4j:WARN Document root element "Configuration", must match DOCTYPE root "null".
    log4j:WARN Continuable parsing error 2 and column 31
    log4j:WARN Document is invalid: no grammar found.
    log4j:ERROR DOM element is - not a <log4j:configuration> element.
    log4j:WARN No appenders could be found for logger (kafka.utils.VerifiableProperties).
    log4j:WARN Please initialize the log4j system properly.
    log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

Answer 1

Problem 1

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

Solution 1

To work with version 2 of log4j aka "log4j2"

-Dlog4j.configuration=

should read

-Dlog4j.configurationFile=

• 1.2 manual: http://logging.apache.org/log4j/1.2/manual.html
• 2.x manual: http://logging.apache.org/log4j/2.x/manual/configuration.html

Problem 2

log4j:WARN ....

Solution 2

In your project, uninclude the log4j-1.2 jar and instead, include the log4j-1.2-api-2.1.jar. I wasn't sure how exactly to exclude the log4j 1.2. I knew that what dependency of my project was requiring it. So, with some reading, I excluded a bunch of stuff.

<dependency>
    <groupId>org.apache.kafka</groupId>
    <artifactId>kafka_2.10</artifactId>
    <version>0.8.2.0</version>
    <exclusions>
        <exclusion>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>                
        </exclusion>
        <exclusion>
            <groupId>org.apache.log4j</groupId>
            <artifactId>log4j-core</artifactId>
        </exclusion>
        <exclusion>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
        </exclusion>          
    </exclusions>
</dependency>

I am not sure which of the exclusions did the trick. Separately, I included a dependency to the 1.2 api which bridges to 2.x.

<!--
    http://logging.apache.org/log4j/2.0/manual/migration.html
    http://logging.apache.org/log4j/2.0/maven-artifacts.html
    Log4j 1.x API Bridge
    If existing components use Log4j 1.x and you want to have this logging
    routed to Log4j 2, then remove any log4j 1.x dependencies and add the
    following.
-->
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-1.2-api</artifactId>
    <version>2.2</version>
</dependency>

Now, the 1.2 logs which were only going to the console actually flow to our 2.x appenders.

Answer 2

If you don't have the fortune of the log4j-1.2.jar on your classpath as Renko points out in his comment , you will only see the message no log4j2 configuration file found .

This is a problem if there is an error in your configuration file, as you will not be told where the problem lies upon start-up.

For instance if you have a log4j2.yaml file which log4j2 fails to process, because for example, you have not configured a YAML parser for your project , or your config is simply incorrect. You will encounter the no log4j2 configuration file found message, with no further information. This is the case even if you have a valid log4j2.xml file, as log4j2 will only attempt to process the first configuration file it finds .

I've found the best way to debug the problem is to explicitly state the configuration file you wish to use as per the command line argument mentioned above .

-Dlog4j.configurationFile=

Hopefully this will help you pinpoint if the issue is actually caused by your classloader not finding the log4j2 configuration file or something else in your configuration.

Update

You can also use the below property to change the default level of the status logger to get further information:

-Dorg.apache.logging.log4j.simplelog.StatusLogger.level=<level>

Answer 3

i had same problem, but i noticed that i have no log4j2.xml in my project after reading on the net about this problem, so i copied the related code in a notepad and reverted the notepad file to xml and add to my project under the folder resources. it works for me.

<?xml version="1.0" encoding="UTF-8"?>
<Configuration 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>
<Root level="DEBUG">
  <AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>

Answer 4

I have been dealing with this problem for a while. I have changed everything as described in this post and even thought error occured. In that case make sure that you clean the project when changing settings in .xml or .properties file. In eclipse environment. Choose Project -> Clean

Answer 5

I use hive jdbc in a java maven project and have the same issues.

My method is to add a log4j2.xml file under src/main/java/resources

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MyClassName {
    private static final Logger LOG = LoggerFactory.getLogger(MyClassName.class);
}

log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<Configuration 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="<your_package_name>.<your_class_name>" level="debug">
        <AppenderRef ref="Console"/>
        </Logger>
        <Root level="WARN">
            <AppenderRef ref="Console"/>
        </Root>
    </Loggers>
</Configuration>

Answer 6

Stuffs I check to verify logging,

1) Check that there're no older log4j versions.

mvn dependency:tree | grep log ## ./gradlew dependencies | grep log
[INFO] +- com.prayagupd:log-service:jar:1.0:compile
[INFO] +- org.apache.logging.log4j:log4j-api:jar:2.6.2:compile
[INFO] +- org.apache.logging.log4j:log4j-core:jar:2.6.2:compile
[INFO] |  \- commons-logging:commons-logging:jar:1.1.1:compile

2) make sure I'm setting log4j2.json properly, which is done with -Dlog4j.configurationFile=???

val logConfig: PropertiesConfiguration = new PropertiesConfiguration("application.properties")
System.setProperty("log4j.configurationFile", logConfig.getString("log4j.config.file"))

println("log4j.configurationFile :: " + System.getProperty("log4j.configurationFile"))

or

Configurator.initialize(null, logConfig.getString("log4j.config.file"));

Also if auto detection is happening make sure the file name is log4j2.* not log4j.*

3) Another check is for parser for log4j2.json. Thanks log4j team for not providing parser within the API.

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.4.0</version>
</dependency>

This might throw an exception if can not find the json parser

[Fatal Error] log4j2.json:1:1: Content is not allowed in prolog.

Answer 7

确保您在.../src/main/resources文件夹下放置了log4j2.*文件而不是log4j.*文件。

Answer 8

In my case I am using the log4j2 Json file log4j2.json in the classpath of my gradle project and I got the same error.

The solution here was to add dependency for JSON handling to my gradle dependencies.

compile group:"com.fasterxml.jackson.core", name:"jackson-core", version:'2.8.4'
compile group:"com.fasterxml.jackson.core", name:"jackson-databind", version:'2.8.4'
compile group:"com.fasterxml.jackson.core", name:"jackson-annotations", version:'2.8.4'

See also documentation of log4j2 :

The JSON support uses the Jackson Data Processor to parse the JSON files. These dependencies must be added to a project that wants to use JSON for configuration:

Answer 9

I am getting this error because log4j2 file got deleted from my src folder

Simply add xml file under src folder

<Appenders>
    <Console name="Console" target="SYSTEM_OUT">
        <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss} [%t] %-5p %c{1}:%L - %msg%n" />
    </Console>

    <RollingFile name="RollingFile" filename="logs/B2CATA-hybrid.log"
        filepattern="${logPath}/%d{yyyyMMddHHmmss}-fargo.log">
        <PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss} [%t] %-5p %c{1}:%L - %msg%n" />
        <Policies>
            <SizeBasedTriggeringPolicy size="100 MB" />
        </Policies>
        <DefaultRolloverStrategy max="20" />
    </RollingFile>

</Appenders>
<Loggers>
   <Logger name="com.pragiti." level="trace" />
    <Root level="info">
        <AppenderRef ref="Console" />
        <AppenderRef ref="RollingFile" />
    </Root>
</Loggers>

Answer 10

I am working on TestNG Maven project, This worked for me by adding <resources> tag in pom.xml , this happens to be the path of my custom configuration file log4j2.xml .

<url>http://maven.apache.org</url>
<properties>
  <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
</properties>
<build>
  <resources>
    <resource>
      <directory>src/main/java/resources</directory>
      <filtering>true</filtering>
    </resource>
  </resources>
  <pluginManagement>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <version>3.0.0-M3</version>
        <configuration>
          <suiteXmlFiles>
            <suiteXmlFile>testng.xml</suiteXmlFile>
          </suiteXmlFiles>
        </configuration>
      </plugin>
    </plugins>
  </pluginManagement>
</build>
<dependencies>
  <dependency>

Answer 11

将xml文件名重命名为log4j2.xml后问题解决

Answer 12

Tested with: log4j-ap 2.13.2, log4j-core 2.13.2.

1. Keep XML file directly under below folder structure. src/main/java
2. In the POM:

 <build> <resources> <resource> <filtering>false</filtering> <directory>src/main/resources</directory> <includes> <include>**/*.xml</include> </includes> </resource> </resources> </build>

3. Clean and build.

Answer 13

I have solve this problem by configuring the build path. Here are the steps that I followed: In eclipse.

1. create a folder and save the logj4 file in it.
2. Write click in the folder created and go to Build path.
3. Click on Add folder
4. Choose the folder created.
5. Click ok and Apply and close.

Now you should be able to run

Answer 14

This sometimes can be thrown before the actual log4j2 configuration file found on the web servlet. at least for my case I think so. Cuz I already have in my web.xml

  <context-param>
    <param-name>log4jConfiguration</param-name>
    <param-value>classpath:log4j2-app.xml</param-value>
  </context-param>

and checking the log4j-web source; in class

org.apache.logging.log4j.web.Log4jWebInitializerImpl

there is the line;

String location = this.substitutor
                 .replace(this.servletContext.getInitParameter("log4jConfiguration"));

all those makes me think that this is temporary log before configuration found.

Answer 15

<?xml version="1.0" encoding="UTF-8"?>
<Configuration 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>
<Root level="DEBUG">
  <AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>

1. Create a new Text document and copy-paste the above code and save it as log4j2.xml.

2. Now copy this log4j2.xml file and paste it under your src folder of your Java project.

3. Run your java program again, you will see error is gone.

Answer 16

Just try below steps, it will work,

1. Keep XML file directly under below folder structure. src/main/java
2. Make sure to save the pom.xml file in case any changes made..

Answer 17

Answer for Intellij users 2022

If you are using Intellij:

Please follow these steps:

1. Put "resources" folder under "YourProject" root and mark it as "Resources Root".

2. Put "log4j2.xml" in resources folder