Spring Boot - no log file written (logging.file is not respected)

Question

I use Spring Boot and want it to write log output to a file.

According to the docs, this is simply done by setting

logging.file=filename.log
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Answer 1

If you are using Maven add the dependency :

    org.slf4j
    slf4j-api
    1.7.6


    org.slf4j
    slf4j-log4j12
    1.7.5

Now you have to specify a file that is called 'log4j.properties' which you have to put in the specific directory : ' src/main/resources/log4j.properties '

Here is how the file should look for example :

# Root logger option
log4j.rootLogger=INFO, file, stdout
log4j.logger.org.springframework.ws.client.MessageTracing.sent=TRACE
log4j.logger.org.springframework.ws.client.MessageTracing.received=TRACE

# 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.springlog.Threshold=INFO
log4j.appender.springlog.layout=org.apache.log4j.PatternLayout
log4j.appender.springlog.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n

# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=D:/example/filename.log
log4j.appender.file.MaxFileSize=10MB
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

Now import these :

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

Declare a logger variable like this :

final static Logger logger = Logger.getLogger(TheClassYourIn.class);

And use it in the class like this :

logger.info("Well hello world then ");

This way it works for me. I hope that this answer will help you . Good luck !

PS: log4j.appender.file.File='directory' is how you specify where the logs to be stored. If you don't specify a directory and just leave it as filename.log this file will be automaticly created in the project dir.