如何正确配置 Log4J？

Question

I'm having trouble using Log4J (version 2.13.0), with the following problems:

• I have no idea if my log4j.properties file is configured properly, or even recognized for that matter.
• Log4J is not using the pattern I've specified nor allowing me to log any trace/debug/info/warn messages.

This is my log4j.properties file:

status = trace
dest = out
name = PropertyConfiguration

property.filename = logs/log%d{yyyy-MM-dd HH:mm:ss}.log
property.pattern = %d{yyyy-MM-dd HH:mm:ss} | [%-5p] %c{1}:%L: %m%n

appender.console.type = Console
appender.console.name = STDOUT
appender.console.layout.type = PatternLayout
appender.console.layout.pattern = ${pattern}

appender.rolling.type = RollingFile
appender.rolling.name = RollingFile
appender.fileName = ${filename}
appender.rolling.filePattern = logs/log-%d{MM-dd-yyyy-HH-mm-ss}.log
appender.rolling.layout.type = PatternLayout
appender.rolling.layout.pattern = ${pattern}
appender.rolling.policies.type = Policies
appender.rolling.policies.time.type = TimeBasedTriggeringPolicy
appender.rolling.policies.time.interval = 2
appender.rolling.policies.time.modulate = true
appender.rolling.strategy.type = DefaultRolloverStrategy
appender.rolling.strategy.max = 5

logger.rolling.name = me.tecc
logger.rolling.level = trace
logger.rolling.additivity = false
logger.rolling.appenderRef.rolling.ref = RollingFile

rootLogger.level = trace
rootLogger.appenderRef.stdout.ref = STDOUT

Any help would be appreciated. Thanks!

Answer 1

Log4J is not using the pattern I've specified nor allowing me to log any trace/debug/info/warn messages.

Unlike its predecessor Log4J 1.x, Log4J 2 did not support configuration through the properties file when it was initially released. It was from Log4J 2.4 that support for the properties file was again added, but with a completely different syntax

I see that your Log4j version is 2.13 which falls below 2.4 , so it wont work.

Kindly pay attention:

The PropertyConfigurator (log4j.properties) does not handle the advanced configuration features supported by the DOMConfigurator (log4j.xml) such as support custom ErrorHandlers, nested appenders such as the AsyncAppender, etc.

Answer 2

appender.fileName = ${filename}

you miss the "rolling" part in this config. try again after change it as follows

appender.rolling.fileName = ${filename}