[LOG4J2-2951] Properties are not resolved with Log4J1 configuration

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.13.3
• Fix Version/s: 2.15.0
• Component/s: Log4j 1.2 bridge
• Assignee: Ralph Goers
• Reporter: Thomas Hackel
• Created: 27/Oct/20 21:08
• Updated: 29/Dec/21 14:43
• Resolved: 05/Dec/21 20:13

Description

When using the log4j 1.2 emulation, the resolution of variables in the log4j.properties does not work.

...
maxbackupindex=20
log4j.appender.RFA=org.apache.log4j.RollingFileAppender
log4j.appender.RFA.MaxBackupIndex=${maxbackupindex}
...

 

I've also created a sample project which shows the problem:

https://github.com/thackel/log4j2-legacy-test

The log4j1 initialization (using system property) works and the property file is read automatically from the classpath, just the variable substitution does not work.

Whats interesting that there is an existing Testcase in Log4J, which shows that it somehow works:

Log4j1ConfigurationFactoryTest.java with its log4j.properties.