log4j configuration via JVM argument(s)?

Question

What variables do I have to set/pass as arguments to the JVM to get log4j to run properly? And by properly I mean not complain and print to the console. Can I see a typical example?

Note: I need to avoid creating a log4j.properties file in the application.

Answer 1

Do you have a log4j configuration file ? Just reference it using

-Dlog4j.configuration={path to file}

where {path to file} should be prefixed with file:

Edit: If you are working with log4j2, you need to use

-Dlog4j.configurationFile={path to file}

Taken from answer https://stackoverflow.com/a/34001970/552525

Answer 2

The solution is using of the following JVM argument:

-Dlog4j.configuration={path to file}

If the file is NOT in the classpath (in WEB-INF/classes in case of Tomcat) but somewhere on you disk, use file:, like

-Dlog4j.configuration=file:C:\Users\me\log4j.xml

More information and examples here: http://logging.apache.org/log4j/1.2/manual.html

Answer 3

This seems to have changed (probably with log4j2) to:

-Dlog4j.configurationFile=file:C:\Users\me\log4j.xml

See: https://logging.apache.org/log4j/2.x/manual/configuration.html

Answer 4

I know this is already answered, but because you said, this isn't exactly what you are looking for, I would like to point out the following alternative:

You can also use a configuration class instead of the properties or xml file.

-Dlog4j.configuratorClass=com.foo.BarConfigurator

See http://logging.apache.org/log4j/1.2/manual.html for details.

Answer 5

Generally, as long as your log4j.properties file is on the classpath, Log4j should just automatically pick it up at JVM startup.

Answer 6

Late to the party as since 2015, Log4J 1.x has reached EOL.

Log4J 2.x onwards the JVM option should be -Dlog4j.configurationFile=<filename>

---

P.S. <filename> could be a file relative to the class path without the file: as suggested in the other answers.

Answer 7

Relative Path is also ok:

java -Dlog4j.configuration=file:".\log4j.properties" -jar com.your-1.0-SNAPSHOT.jar

or

java -Dlog4j.configuration=file:".\log4j.xml" -jar com.your-1.0-SNAPSHOT.jar

Answer 8

If you are using gradle. You can apply 'aplication' plugin and use the following command

  applicationDefaultJvmArgs = [
             "-Dlog4j.configurationFile=your.xml",
                              ]