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log4j, need to display only INFO and ERROR message in log file

I am new to log4j and worked to setup on eclipse and its running. I understood the chain of priority in the levels and this is my properties file config:
log4j.rootLogger=ALL, file, console
log4j.appender.console=org.apache.log4j.ConsoleAppender
logrj.appender.console.Target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%-5p %c{1} - %m%n
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=logs/justfortesting.log
log4j.appender.file.Append=true
log4j.appender.file.ImmediateFlush=true
log4j.appender.file.MaxFileSize=1KB
log4j.appender.file.MaxBackupIndex=2
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d %d{Z} [%t] %-5p (%F:%L) - %m%n
My question is
Is it possible to print only INFO and ERROR type of messages in log files with properties file configuration

Finally I got the solution for my requirement. Here I used concept of filters i.e LevelRangeFilter. And for every logging level we defined appender.
log4j.rootLogger=DEBUG, file, console, file1
log4j.appender.console=org.apache.log4j.ConsoleAppender
logrj.appender.console.Target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%-5p %c{1} - %m%n
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=logs/justfortesting.log
log4j.appender.file.Append=true
log4j.appender.file.ImmediateFlush=true
log4j.appender.file.Threshold=DEBUG
log4j.appender.file.filter.a=org.apache.log4j.varia.LevelRangeFilter
log4j.appender.file.filter.a.LevelMin=INFO
log4j.appender.file.filter.a.LevelMax=INFO
log4j.appender.file.MaxFileSize=1KB
log4j.appender.file.MaxBackupIndex=2
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d %d{Z} [%t] %-5p (%F:%L) - %m%n
log4j.appender.file1=org.apache.log4j.RollingFileAppender
log4j.appender.file1.File=logs/justfortesting.log
log4j.appender.file1.Append=true
log4j.appender.file1.ImmediateFlush=true
log4j.appender.file1.Threshold=DEBUG
log4j.appender.file1.filter.g=org.apache.log4j.varia.LevelRangeFilter
log4j.appender.file1.filter.g.LevelMin=ERROR
log4j.appender.file1.filter.g.LevelMax=ERROR
log4j.appender.file1.MaxFileSize=1KB
log4j.appender.file1.MaxBackupIndex=2
log4j.appender.file1.layout=org.apache.log4j.PatternLayout
log4j.appender.file1.layout.ConversionPattern=%d %d{Z} [%t] %-5p (%F:%L) - %m%n
log4j.logger.com.log4j=DEBUG, file, console, file1
log4j.additivity.com.log4j=false
If any one suggest to reduce the above properties configuration for same requirement,, please comment.

Try
log4j.appender.file.Threshold=INFO
Also see related SO question and documentation

Custom layout for log4j

There is a way to print different layout for different log level? For example:
logger.warn("Message");
print something like this: 2016-06-20 13:34:41,245 INFO (main:) Message
and for logger.info("Message2");
print just: Message2
Is possible to do that? To define one layout to warn e other layout for info
log4j.properties
# Root logger option
log4j.rootLogger=INFO, file, stdout
# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=log4j.log
log4j.appender.file.MaxFileSize=10MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%m%n %d %-5p [%c] (%t:%x) %m%n
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %-5p [%c] (%t:%x) %m%n

I haven't tested but it should work. If you define two appenders and you assign a pattern for each appenders. Then the keyword Threshold should filter the level
:
# Root logger option
log4j.rootLogger=INFO, fileWarning, fileInfo, stdout
log4j.appender.fileWarning=org.apache.log4j.RollingFileAppender
log4j.appender.fileWarning.File=log4j.log
log4j.appender.fileWarning.MaxFileSize=10MB
log4j.appender.fileWarning.MaxBackupIndex=10
log4j.appender.fileWarning.layout=org.apache.log4j.PatternLayout
log4j.appender.fileWarning.layout.ConversionPattern=%m%n %d %-5p [%c] (%t:%x) %m%n
log4j.appender.fileWarning.Threshold=WARNING
log4j.appender.fileInfo=org.apache.log4j.RollingFileAppender
log4j.appender.fileInfo.File=log4j.log
log4j.appender.fileInfo.MaxFileSize=10MB
log4j.appender.fileInfo.MaxBackupIndex=10
log4j.appender.fileInfo.layout=org.apache.log4j.PatternLayout
log4j.appender.fileInfo.layout.ConversionPattern=%m%n
log4j.appender.fileInfo.Threshold=INFO
Hope it's help.

Java Log4J Logger Messages

I am working on log4j with Java. I am redirecting all my applications logger messages to a specific folder inside my project like this:
logs/log4j-MyFirstClass.log
If I want to redirect specific file messages to specific log file, for ex: ABC.java logger messages to ABC.log file, then how should I change this log4J.properties file ? Please help. Here is my log4j.properties file:
# Root logger option
log4j.rootLogger=DEBUG, stdout, file
# Redirect log messages to console
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Redirect log messages to a log file, support file rolling.
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=logs/log4j-MyFirstClass.log
log4j.appender.file.MaxFileSize=5MB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

You need to define an appender for each file, then specify which packages use which appender.
# Root logger option; everything logs to console at debug
log4j.rootLogger=INFO, stdout
# Classes in package com.foo.bar will use the file1 appender
log4j.logger.com.foo.bar=file1
# Classes in package com.whizz.bang will use the file2 appender, note we also overrode the default log level
log4j.logger.com.whizz.bang=DEBUG, file2
# Redirect log messages to console
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Appender for file 1
log4j.appender.file1=org.apache.log4j.RollingFileAppender
log4j.appender.file1.File=logs/log4j-first.log
log4j.appender.file1.MaxFileSize=5MB
log4j.appender.file1.MaxBackupIndex=10
log4j.appender.file1.layout=org.apache.log4j.PatternLayout
log4j.appender.file1.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Appender for file 2
log4j.appender.file2=org.apache.log4j.RollingFileAppender
log4j.appender.file2.File=logs/log4j-second.log
log4j.appender.file2.MaxFileSize=5MB
log4j.appender.file2.MaxBackupIndex=10
log4j.appender.file2.layout=org.apache.log4j.PatternLayout
log4j.appender.file2.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

Is there a way to define default layout?

# Root logger option
log4j.rootLogger=ALL, stdout, A1
log4j.logger.org.apache.jsp=ALL, stdout, A1
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} [%p] [%c:%L] - %m%n
# LOG4J daily rolling log files configuration
log4j.appender.A1=org.apache.log4j.DailyRollingFileAppender
log4j.appender.A1.File=logs/file.log
log4j.appender.A1.DatePattern='.'yyyy-MM-dd
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} [%p] [%c:%L] - %m%n
Most of the time I define several appenders... one for Console and some others into files. But most of the time I used the same layout for the output.
Is there a way to define a default one ?
Something like that ?
log4j.appender.layout=org.apache.log4j.PatternLayout
log4j.appender.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} [%p] [%c:%L] - %m%n

# Root logger option
log4j.rootLogger=ALL, stdout, A1
log4j.logger.org.apache.jsp=ALL, stdout, A1
PATTERN=%d{yyyy-MM-dd HH:mm:ss} [%p] %l - %m%n
# Direct log messages to stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=${PATTERN}
# LOG4J daily rolling log files configuration
log4j.appender.A1=org.apache.log4j.DailyRollingFileAppender
log4j.appender.A1.File=logs/file.log
log4j.appender.A1.DatePattern='.'yyyy-MM-dd
log4j.appender.A1.layout=org.apache.log4j.PatternLayout
log4j.appender.A1.layout.ConversionPattern=${PATTERN}
It seems that the only way to do this is to set a variable, as I've done with PATTERN=%d{yyyy-MM-dd HH:mm:ss} [%p] %l - %m%n

multiple fileappenders in log4j

I have to put the log info in two separate log files based on some condition.how to do that.
here is my logging.properties file
log4j.rootLogger=debug, stdout, R
log4j.appender.stdout=org.apache.log4j.RollingFileAppender
log4j.appender.stdout.File=${catalina.home}/logs/std.log
log4j.appender.stdout.MaxFileSize=200KB
log4j.appender.stdout.MaxBackupIndex=2
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d [%c] %p - %m%n
log4j.appender.R=org.apache.log4j.RollingFileAppender
log4j.appender.R.File=${catalina.home}/logs/demo.log
log4j.appender.R.MaxFileSize=200KB
log4j.appender.R.MaxBackupIndex=2
log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%d [%c] %p - %m%n

You can define multiple appenders and assign java packages to the appenders. In the example below all classes in com.mycorp.web will log to web.log at DEBUG level and classes in com.mycorp.db will log to db.log at INFO level.
log4j.rootLogger=debug, weblogger, dblogger
#Define which packages use which appenders
log4j.logger.com.mycorp.web=DEBUG,weblogger
log4j.logger.com.mycorp.db=INFO,dblogger
#Ensure the logs don't add to each other
log4j.additivity.com.mycorp.web=false
log4j.additivity.com.mycorp.db=false
#Define web appender
log4j.appender.weblogger=org.apache.log4j.DailyRollingFileAppender
log4j.appender.weblogger.File=/var/log/myapp/web.log
log4j.appender.weblogger.DatePattern='.'yyyy-MM-dd
log4j.appender.weblogger.Append=true
log4j.appender.weblogger.layout=org.apache.log4j.PatternLayout
log4j.appender.weblogger.layout.ConversionPattern=%d [%t] %-5p %c{1} - %m %n
#Define db appender
log4j.appender.dblogger=org.apache.log4j.DailyRollingFileAppender
log4j.appender.dblogger.File=/var/log/myapp/db.log
log4j.appender.dblogger.DatePattern='.'yyyy-MM-dd
log4j.appender.dblogger.Append=true
log4j.appender.dblogger.layout=org.apache.log4j.PatternLayout
log4j.appender.dblogger.layout.ConversionPattern=%d [%t] %-5p %c{1} - %m %n

Based on your condition, you can grab different loggers.
Logger x = predicate() ? Logger.getLogger("wombat") : Logger.getLogger("other");
http://logging.apache.org/log4j/1.2/manual.html (Search for "wombat" for the relevant code.)

If you want different file for some logger, you should write something like this:
log4j.logger.LOGGER_ONE=DEBUG, stdout
log4j.logger.LOGGER_TWO=WARN, R