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Do i have to create appenders for all classes in log4j?

I'm using log4j for my final project. I tested it using single class before I used log4j in my project. That worked fine.
Then I added log4j to my project and I used it in many classes using:
final static Logger logger = Logger.getLogger(Supplier.class);
Then I got a warning:
log4j:WARN No appenders could be found for logger (classes.Supplier).
log4j:WARN Please initialize the log4j system properly.
This is my properties file:
# Root logger option
log4j.rootLogger=DEBUG, file
log4j.rootLogger=DEBUG, errorfile
# Redirect log messages to console
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.errorfile=org.apache.log4j.RollingFileAppender
# Redirect log messages to a log file, support file rolling.
log4j.appender.file.File=C:\\HardwareLog\\INFO.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
log4j.appender.errorfile=C:\\HardwareLog\\ERROR.log
log4j.appender.errorfile.Threshhold=ERROR
log4j.appender.errorfile.MaxFileSize=5MB
log4j.appender.errorfile.MaxBackupIndex=10
log4j.appender.errorfile.layout=org.apache.log4j.PatternLayout
log4j.appender.errorfile.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
Do I have to create appenders for each class to use it?
Can I use one properties file in different packages ?

I found a solution. I removed root logger and added two loggers for my two packages.
log4j.logger.package1=DEBUG,FIRST
log4j.logger.package2=DEBUG,SECOND
now its working fine.

you can go for root logger that will log for the entire application.
# Root logger option
log4j.rootLogger=INFO, file
plese go through this link
https://www.mkyong.com/logging/log4j-log4j-properties-examples/

All log4j appenders defined in log4j.properties in play

My log4j.properties file is pasted below. My understanding is that we need to add Appenders to the root logger for the appender to work. As you can see in the below properties file, only appender A is attached to the root logger (log4j.rootLogger=info, A). However, what I see is that the logging information is printed to both the appenders (ConsoleAppender - A and File Appender - B). How is this possible?
log4j.rootLogger=info, A
log4j.appender.A=org.apache.log4j.ConsoleAppender
log4j.appender.A.layout=org.apache.log4j.PatternLayout
log4j.appender.A.layout.ConversionPattern=%-4r [%t] [rid=%X{RID} ] %-5p %c %x - %m%n
log4j.appender.B=org.apache.log4j.FileAppender
log4j.appender.B.layout=org.apache.log4j.PatternLayout
log4j.appender.B.file=target/server.log
log4j.appender.B.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n

Well, it turns out that the Console appender (A) was printing out to the server.log (glassfish log) which incidentally is also the name of the log file associated with appender B.
The following property was attached to the glassfish server (startup parameters) which helped me understand which log4j.properties (in case of stray properties file) file is loaded along with information like what appenders are used for logging.
-Dlog4j.debug=true

Different logging appender on LOG4J

I'm using log4j 1.2 and I need to:
log everything (including logging from referenced libraries) to console
log from my code to file (and maybe to console)
Using the following code:
log4j.rootLogger=DEBUG, CONSOLE
log4j.com.mypackage=ALL, CONSOLE, CSV
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.Target=System.err
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.conversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %-5p - %m%n
log4j.appender.CSV=org.apache.log4j.FileAppender
log4j.appender.CSV.File=./myfile.csv
log4j.appender.CSV.Append=false
log4j.appender.CSV.layout=org.apache.log4j.PatternLayout
log4j.appender.CSV.layout.conversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %-5p - %m%n
The logfile is not created.
Other try I done:
If I add CSV appender to rootLogger, then the file is created and filled.
If I add CSV appender to rootLogger and disable it, then the file is just created.
If I log only my logger to console... the it works fine
Do you have any idea to solve?
Thanks

You are missing an important part.
The value has to be
log4j.logger.com.mypackage
Note that you are missing logger in the log definition

Log4j output on console instead of configured file

I configured Log4j to log into a file but it is instead logging to stdout.
it creates the log file but it does not write to it, instead to stdout.
Here is my config file:
log4j.rootCategory=INFO, file, mail
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=/path-to/jobs-batch.log
log4j.appender.file.MaxFileSize=10MB
log4j.appender.file.MaxBackupIndex=2
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=[jobs-batch] %p [%t] %c{1}.%M(%L) | %m%n
log4j.logger.org.springframework.jdbc=WARN
# Configuration for receiving e-mails when ERROR messages occur.
log4j.appender.mail=org.apache.log4j.net.SMTPAppender
log4j.appender.mail.To=xxx#xxx.com
log4j.appender.mail.From=xxx#xxx.com
log4j.appender.mail.SMTPHost=mail.xxx.de
log4j.appender.mail.Threshold=ERROR
log4j.appender.mail.Subject=Jobs Batch Error
log4j.appender.mail.layout=org.apache.log4j.PatternLayout
log4j.appender.mail.layout.ConversionPattern=%d %-5p %c %x - %m%n
any ideas?
Thanks

Adjust to suite your needs:
log4j.rootCategory=DEBUG, C
log4j.appender.C=org.apache.log4j.ConsoleAppender
log4j.appender.C.layout=org.apache.log4j.PatternLayout
log4j.appender.C.layout.ConversionPattern=%d{MMddyyyy HH:mm} %-5p %c{1}:%L - %m%n
log4j.appender.C.Target=System.out

Things to check:
What is the name of your Log4j property file? The default is log4j.properties, which is what the Log4j library will look for on startup.
Related to what Thorbjorn asks in his comment, where is the log4j property file located? Placing it in the default package will ensure it's found (by default Log4j searches the classpath).
Optionally specify the location of the log4j property file using the log4j.configuration property when starting the JVM.

i was stupid by myself.
i was using the -Dlog4j.configuration to set my file.
BUT i was also configuring log4j programmatically to use the SAME configuration file.
i still do not understand why it did behave like that since i was just setting the SAME configuration file twice. But once i did it only once it worked as expected.

Web Service and Log4J Output to File

So, I have the log4j configurations set up and it output to the console just fine. But I need it to output to a file now. I am using Axis2 in Eclipse Galileo.
I edited the default log4j.properties file to this:
Set root category priority to INFO and its only appender to CONSOLE.
log4j.rootCategory=INFO, CONSOLE
log4j.rootCategory=INFO, CONSOLE, LOGFILE
Set the enterprise logger priority to FATAL
log4j.logger.org.apache.axis2.enterprise=FATAL
log4j.logger.de.hunsicker.jalopy.io=FATAL
log4j.logger.httpclient.wire.header=FATAL
log4j.logger.org.apache.commons.httpclient=FATAL
CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=[%p] %m%n
LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=C:\Users\*username*\Desktop\Android\Android_WS\src\wtp\AndroidWS_Log.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=%d [%t] %-5p %c %x - %m%n
But the output is still not getting to the Log file. Any help would be much appreciated. Thanks Guys!

Remove line 2:
log4j.rootCategory=INFO, CONSOLE
Also, try using a forward slash, '/' for the directory separator:
log4j.appender.LOGFILE.File=C:/Users/*username*/Desktop/Android/Android_WS/src/wtp/AndroidWS_Log.log

Make sure that your server has write access rights to the log file.