Log4J creates log file but does not write to it

The output seems to be of the default format that Java's standard logging framework (JUL) would emit.

So, there are two possibilities (that come to mind):

  1. Your code imports java.util.logging.Logger, rather than org.apache.log4j.Logger.
  2. There exists a library of some sort, in your classpath, that intercepts Log4J calls and converts them to JUL calls.

I had the same problem as you. File was created, but without any logs in it just in console. And it was because of incorrect dependencies in maven project in my case.

My log4j.properties file was:

# Root logger option
log4j.rootLogger=DEBUG, file

# Direct log messages to a log file
# configuration to print into file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.MaxFileSize=1MB
log4j.appender.file.MaxBackupIndex=10
# Define the layout for file appender
log4j.appender.file.layout=org.apache.log4j.PatternLayout
#log4j.appender.file.layout.ConversionPattern=[%t] %-5p %c %x - %m%n
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n
# Set the name of the file
log4j.appender.file.File=C:\\log\\logging.log
# Set the append to false, overwrite
log4j.appender.file.Append=false

And I used in POM:

<dependency>
  <groupId>org.slf4j</groupId>
  <artifactId>slf4j-simple</artifactId>
  <version>1.6.2</version>
</dependency>
    
<dependency>
  <groupId>log4j</groupId>
  <artifactId>log4j</artifactId>
  <version>1.2.17</version>
</dependency>

Yes, it created for me file where I needed it, but logs were in console. Then I changed it to another dependency like:

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.7.5</version>
</dependency>

And I finally got it in file instead of console. Even without any explicit commands like PropertyConfigurator.configure().