ERROR StatusLogger Log4j2 could not find a logging implementation

30
votes

I am trying to implement log4j 2 but it keeps throwing the following error.

> ERROR StatusLogger Log4j2 could not find a logging implementation.
> Please add log4j-core to the classpath. Using SimpleLogger to log to
> the console...  
> ERROR LogExample This Will Be Printed On Error 
> FATAL LogExample This Will Be Printed On Fatal

I have tried the solution given on the net. But the don't seem to be working for me.

This is the code that I am trying to run.

package demo;

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

public class LogExample {

    private static final Logger LOG = LogManager.getLogger(LogExample.class);

    public static void main(String[] args) {

        LOG.debug("This Will Be Printed On Debug");
        LOG.info("This Will Be Printed On Info");
        LOG.warn("This Will Be Printed On Warn");
        LOG.error("This Will Be Printed On Error");
        LOG.fatal("This Will Be Printed On Fatal");
        LOG.info("Appending string: {}.", "Hello, World");
    }

}

Project and dependency added in the pom.xml:

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Any help is appreciated.

5
javaeclipselog4j2
You need to add the log4j-core jar to the classpath. I suppose you are using maven so basically you can do that by creating a jar with all the dependencies (instead of a jar containing only your code). You can take a look at the maven shade plugin to do so. - Cristian Ramon-Cortes
Please consider accepting one of the answers if it was useful or post your own if you managed to solve it in another way. - Cristian Ramon-Cortes
Thanks for the reminder. I found another ways I have posted it as another answer. Really appreciate your help. - Alok

5 Answers

7
votes

Solved the error message by setting the system property for log4j2 configuration file. below is the below code.

System.setProperty("log4j.configurationFile","./path_to_the_log4j2_config_file/log4j2.xml");

Logger log = LogManager.getLogger(LogExample.class.getName());
7
votes

This dependency help to avoid this error from lambda.

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-to-slf4j</artifactId>
    <version>2.8.2</version>
</dependency>
5
votes

To get around a similar issue with Spring Boot I added 

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-log4j2</artifactId>
</dependency>

to my POM

4
votes

if you already added log4j-core to maven pom, you dont need anything more it should work. Problem could be with your IDE, that does not see your maven dependency. Try reloading or reimporting maven dependencies, or restarting your IDE also can help.

1
votes

In my case the error was related with the version of maven-shade-plugin (3.2.2).

It works when I set this plugin to version 3.2.1