CODEWITHSUNDEEP
log4jlog4j2
Mariusz
Mariusz

Reputation: 1985

log4j-1.2-api bridge ClassNotFoundException:org.apache.log4j.RollingFileAppender

I try to migrate my application from log4j to log4j2. According to official manual I have org.apache.logging.log4j:log4j-1.2-api:2.17.1, org.apache.logging.log4j:log4j-api:2.17.1 and org.apache.logging.log4j:log4j-core:2.17.1 in my maven dependencies. I use log4j.properties file so I enabled compatibility mode (-Dlog4j1.compatibility=true). RollingFileAppender is configured in my log4j.properties file:

log4j.appender.A2=org.apache.log4j.RollingFileAppender

I get following error:

2022-02-16 21:04:20,396 main ERROR Unable to create Appender org.apache.log4j.RollingFileAppender due to ClassNotFoundException:org.apache.log4j.RollingFileAppender

According to official manual, RollingFileAppender is a supported component. I had log4j:log4j:1.2.17 dependency before migration to log4j2 and it contains org.apache.log4j.RollingFileAppender class. Unfortunately none of the log4j-1.2-api,log4j-api and log4j-core libraries contain this class. I do not understand why RollingFileAppender is not present in log4j bridge if manual says that RollingFileAppender is supported component. I have found similar question but without a satisfactory answer. How to migrate RollingFileAppender?

UPDATE

Here is my log4j.properties file:

log4j.rootCategory=INFO, A1, A2

log4j.appender.A1=org.apache.log4j.ConsoleAppender
log4j.appender.A2=org.apache.log4j.RollingFileAppender

log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%d%m%M %n

log4j.appender.A2.file=C:/projects/test/Log.log
#log4j.appender.A2.layout=org.apache.log4j.PatternLayout
#log4j.appender.A2.layout.ConversionPattern=[%d{dd.MM HH.mm.ss.SSS} %-5p %-20c{1}] : %m%n
#log4j.appender.A2.MaxFileSize=10000KB
#log4j.appender.A2.MaxBackupIndex=3

I added -Dlog4j2.debug=true. There are tons of logs. I chose interesting logs:

TRACE StatusLogger Trying to find [log4j.properties] using context class loader jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc.
DEBUG StatusLogger Not in a ServletContext environment, thus not loading WebLookup plugin.
DEBUG StatusLogger PluginManager 'Log4j Builder' found 18 plugins
DEBUG StatusLogger Parsing for [root] with value=[INFO, A1, A2].
DEBUG StatusLogger Level token is [INFO].
DEBUG StatusLogger Logger root level set to INFO
DEBUG StatusLogger Parsing appender named "A1".
DEBUG StatusLogger PluginManager 'Converter' found 47 plugins
DEBUG StatusLogger Starting OutputStreamManager SYSTEM_OUT.false.false
DEBUG StatusLogger Adding appender named [A1] to loggerConfig [].
DEBUG StatusLogger Parsing appender named "A2".
WARN StatusLogger Unable to create File Appender, no file name provided
ERROR StatusLogger Unable to create Appender org.apache.log4j.RollingFileAppender due to ClassNotFoundException:org.apache.log4j.RollingFileAppender
DEBUG StatusLogger Appender named [A2] not found.
DEBUG StatusLogger Finished configuring.

Upvotes: 2

Views: 2469

Answers (1)

Piotr P. Karwasz
Piotr P. Karwasz

Reputation: 16045

The reason configuration fails is explained by the following message:

WARN StatusLogger Unable to create File Appender, no file name provided

This is caused by a compatibility problem between the Log4j 1.x bridge and the original Log4j 1.x: property names must start with a capital letter (cf. LOG4J2-3316). This will be solved in the next release.

Until then, you can use:

log4j.appender.A2.File=C:/projects/test/Log.log

(with a capital F).

Upvotes: 2

Related Questions