log4j properties DailyRollingFileAppender does not

问题:

I want daily logs with the log file appended with the date in yyyy-dd-mm format. When I use DailyRollingFileAppender, a new log file is not created. The logs are written to the same log file. Also, the date Pattern provided is not considered. The log file created is LoggerFile.log. And every content(even on the next day) is written to this file.

I am using the log4j-1.2.17 jar. I am developing in Netbeans 7.3.1 in Java.

Is there anyone using this JAR and facing such a problem. Please help!

Here is the content of the properties file I use:

# Root logger option
log4j.rootLogger=ERROR,FILE,stdout

# Define the file appender
log4j.appender.FILE=org.apache.log4j.DailyRollingFileAppender

log4j.appender.FILE.File=.//..//logs//LoggerFile.log

# Define the layout for file appender
log4j.appender.FILE.DatePattern='.'yyyy-MM-dd
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.conversionPattern=%d{yyyy-MM-dd HH:mm:ss.SSS zzz} %5p     %c{1}:%L - %m%n

log4j.appender.FILE.MaxFileSize=10MB


# 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.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L -  %m%n`

回答1:

I had similar requirements of daily log file rotation.. (Though the question is older, thought the answer would help others)..

Key points:

1. First of all, we can avoid using DailyRollingFileAppender. Why? DailyRollingFileAppender has been observed to exhibit synchronization issues and data loss. The log4j extras companion includes alternatives which should be considered for new deployments and which are discussed in the documentation for org.apache.log4j.rolling.RollingFileAppender. Reference: Documentation of Daily Rolling File Appender

2. Apache extras log4j, Would suggest to use org.apache.log4j.rolling.RollingFileAppender with the Time based rolling policy

3. May find a sample configuration for time based rotation of log.

Hope this helps.

回答2:

First of all you have an error because the DailyRollingFileAppender does not support the property MaxFileSize.

Then you can try to remove the char ' from the DatePattern:

Try changing

log4j.appender.FILE.DatePattern='.'yyyy-MM-dd

to

log4j.appender.FILE.DatePattern=.yyyy-MM-dd

回答3:

Try to add another line log4j.appender.file.Append=true

The full code looks like below

            # Root logger option
            log4j.rootLogger=DEBUG, file, stdout

            # Daily rolling file appender
            log4j.appender.file=org.apache.log4j.DailyRollingFileAppender
            log4j.appender.file.File=logs/mylogs.log
            log4j.appender.file.Append=true
            log4j.appender.file.DatePattern='.'dd-MM-yyyy
            log4j.appender.file.MaxFileSize=10MB
            log4j.appender.file.MaxBackupIndex=100
            log4j.appender.file.encoding=UTF-8
            log4j.appender.file.layout=org.apache.log4j.PatternLayout
            log4j.appender.file.layout.ConversionPattern=%d{dd-MM-yyyy HH:mm:ss} %-5p %c{1}:%L - %m%n