Java log4j2 configuration using different files for different log levels

property.pattern = %d \[%t\] %F %-5L %-5p %c - %m%n
--- Appender 0: Console (All levels) ---
appender.0.type = Console
appender.0.name = ALLLOGCONSOLE
appender.0.layout.type = PatternLayout
appender.0.layout.pattern = ${pattern}
--- Appender 1: All Log File (All levels) ---
appender.1.type = File
appender.1.name = ALLLOGFILE
appender.1.fileName = logs/all.log
appender.1.layout.type = PatternLayout
appender.1.layout.pattern = ${pattern}
--- Appender 4: ERROR ONLY ---
appender.4.type = File
appender.4.name = ERRORLOGFILE
appender.4.fileName = logs/error.log
appender.4.layout.type = PatternLayout
appender.4.layout.pattern = ${pattern}
appender.4.filter.threshold.type = LevelMatchFilter
appender.4.filter.threshold.level = ERROR
appender.4.filter.threshold.onMatch = ACCEPT
appender.4.filter.threshold.onMismatch = DENY
--- Appender 5: WARN ONLY ---
appender.5.type = File
appender.5.name = WARNLOGFILE
appender.5.fileName = logs/warn.log
appender.5.layout.type = PatternLayout
appender.5.layout.pattern = ${pattern}
appender.5.filter.threshold.type = LevelMatchFilter
appender.5.filter.threshold.level = WARN
appender.5.filter.threshold.onMatch = ACCEPT
appender.5.filter.threshold.onMismatch = DENY
--- Appender 6: INFO ONLY ---
appender.6.type = File
appender.6.name = INFOLOGFILE
appender.6.fileName = logs/info.log
appender.6.layout.type = PatternLayout
appender.6.layout.pattern = ${pattern}
appender.6.filter.threshold.type = LevelMatchFilter
appender.6.filter.threshold.level = INFO
appender.6.filter.threshold.onMatch = ACCEPT
appender.6.filter.threshold.onMismatch = DENY
--- Appender 7: DEBUG ONLY ---
appender.7.type = File
appender.7.name = DEBUGLOGFILE
appender.7.fileName = logs/debug.log
appender.7.layout.type = PatternLayout
appender.7.layout.pattern = ${pattern}
appender.7.filter.threshold.type = LevelMatchFilter
appender.7.filter.threshold.level = DEBUG
appender.7.filter.threshold.onMatch = ACCEPT
appender.7.filter.threshold.onMismatch = DENY
--- Appender 8: TRACE ONLY ---
appender.8.type = File
appender.8.name = TRACELOGFILE
appender.8.fileName = logs/trace.log
appender.8.layout.type = PatternLayout
appender.8.layout.pattern = ${pattern}
appender.8.filter.threshold.type = LevelMatchFilter
appender.8.filter.threshold.level = TRACE
appender.8.filter.threshold.onMatch = ACCEPT
appender.8.filter.threshold.onMismatch = DENY
--- Root Logger Configuration ---
Set level to TRACE so all events are captured, then filtered by appenders
rootLogger.level = TRACE
rootLogger.appenderRef.0.ref = ALLLOGCONSOLE
rootLogger.appenderRef.1.ref = ALLLOGFILE
rootLogger.appenderRef.4.ref = ERRORLOGFILE
rootLogger.appenderRef.5.ref = WARNLOGFILE
rootLogger.appenderRef.6.ref = INFOLOGFILE
rootLogger.appenderRef.7.ref = DEBUGLOGFILE
rootLogger.appenderRef.8.ref = TRACELOGFILE

Key Changes Explained

1. LevelMatchFilter: This is the magic ingredient.

   • onMatch = ACCEPT means if the log level is exactly what we specified, write it.

   • onMismatch = DENY means if it is anything else (even a "higher" level like ERROR in an INFO file), ignore it.

2. RootLogger Level: I changed the rootLogger.level to TRACE. If the root level is set to something higher (like ERROR), then INFO and DEBUG messages would be discarded before they ever reach the appenders, regardless of the filters.

3. Removed individual Loggers: In your original snippet, you had specific loggers for names like de.hoelzer.info.log.file. Unless you are specifically creating loggers in Java with those exact names (LogManager.getLogger("de.hoelzer.info.log.file")), they aren't doing anything. It is much cleaner to let the rootLogger handle the flow and let the Appenders decide which file the message goes into based on the level.