How do you configure log4j.properties to have exactly one logfile per run of an app. I've read that you should use a timestamp in the filename but that will create many files per run as time goes by.
I tried DailyRollingFileAppender and RollingFileAppender but can't find a way to configure exctly one log per run. The log should not be broken into multiple logs and it shouldn't be truncated and files of old runs should be preserved.
Each class has a static org.slf4j.Logger for it's own class name:
private static final Logger log = LoggerFactory.getLogger(Foo.class);
This is my current log4j.properties
log4j.rootLogger=error, RootAppender, RootErrorAppender
#log4j.logger.com.example=info, qspaBackendAppender, stderr
log4j.logger.com.example=info, qspaBackendAppender
log4j.additivity.com.example=true
#log4j.logger.com.example.util=trace, qspaBackendAppender, stderr
#log4j.additivity.com.example.util=true
log4j.appender.qspaBackendAppender=org.apache.log4j.DailyRollingFileAppender
log4j.appender.qspaBackendAppender.file=logs/qspaBackend.log
log4j.appender.qspaBackendAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.qspaBackendAppender.layout.ConversionPattern=<%d{yyyy-MM-dd HH:mm:ss}> %-5p : %C{1} %c{2} : %m%n
log4j.appender.stderr=org.apache.log4j.ConsoleAppender
log4j.appender.stderr.Target=System.err
log4j.appender.stderr.layout=org.apache.log4j.PatternLayout
log4j.appender.stderr.layout.ConversionPattern=%-5p %c{1}:%L - %m%n
log4j.appender.RootAppender=org.apache.log4j.RollingFileAppender
log4j.appender.RootAppender.file=logs/root.log
log4j.appender.RootAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.RootAppender.layout.ConversionPattern=<%d{yyyy-MM-dd HH:mm:ss}> %-5p : %C{1} %c{2} : %m%n
log4j.appender.RootErrorAppender=org.apache.log4j.RollingFileAppender
log4j.appender.RootErrorAppender.file=logs/rootError.log
log4j.appender.RootErrorAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.RootErrorAppender.layout.ConversionPattern=<%d{yyyy-MM-dd HH:mm:ss}> %-5p : %C{1} %c{2} : %m%n
log4j.appender.RootErrorAppender.threshold=error
Combine the answer of Udo Klimaschewski and the answer from this question in order to get the desired result.