Log4j记录信息消息而不记录警告消息

Question

I'm trying to log certain info messages onto a file but as soon as I run the application both warn and info messages are logged. Now, from what I've read from this site , you cannot log one without logging the other. Has anyone tried this before? If so, how did your properties file look like?

My properties file looks like this:

 ***** Set root logger level to INFO and its two appenders to stdout and R.
log4j.rootLogger=INFO, stdout, R

# ***** stdout is set to be a ConsoleAppender.
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
# ***** stdout uses PatternLayout.
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
# ***** Pattern to output the caller's file name and line number.
log4j.appender.stdout.layout.ConversionPattern=%5p [%M has started] (%F:%L) - %m%n
/
# ***** R is set to be a RollingFileAppender.
log4j.appender.R=org.apache.log4j.DailyRollingFileAppender
log4j.appender.R.DatePattern='.'yyyy-MM-dd-HH
log4j.appender.R.File="folder where log will be saved"
log4j.appender.R.layout.ConversionPattern=%5p [%m has started] %c{2}.[%x] (%F:%L) %d{yyyy-MM-dd HH:mm:ss} - %m%n

# ***** R uses PatternLayout.
log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%5p [%m has started] %c{2}.[%x] (%F:%L) %d{yyyy-MM-dd HH:mm:ss} - %m%n

Answer 1

AFAIK there's no standard way to suppress higher log levels than those you are interested in.

However, you might be able to use a custom appender to do that.

It might look similar to this:

public class MyAppender extends AppenderSkeleton {
  protected void append(LoggingEvent event) {
    if( event.getLevel() == Level.INFO ) {
      //append here, maybe call a nested appender
    }
  }
}

Answer 2

The log level WARN is higher than INFO , and the logging configuration defines the minimum threshold level to be logged by the appender. So, all messages higher than that level will also be logged.

Hence, the WARN messages are expected. And I don't think you can configure it to the way you want.

Answer 3

If the WARN messages that should not be printed come from a different package than the INFO messages, then you can define different log levels for these packages. The first can specify level ERROR and the second INFO

it should look something like this: log4j.logger.com.test.something=ERROR log4j.logger.com.other.package=INFO

cheers

Answer 4

Why do you want to filter the WARN level? As peshkira said, you could use two different loggers for splitting/filtering your log output, or you could use tools like grep for filtering (offline) or you could simply remove the WARN logs from your code if your don't need them anyway.

Answer 5

As far as I understand, advanced filters like LevelMatchFilter and LevelRangeFilter can do the trick for you.

Thing worth keeping in mind though is that using these may require xml config instead of properties: Can't set LevelRangeFilter for log4j