log4j. Rollover each hour, zip daily

Question

Can I configure log4j to rollover each hour, then compress all the daily log-files into one zip (so that zip contains 24 log-files).

Ideally I'd like to zip files only for those days which are one week old and earlier. But that's another part of the question.

Answer 1

You probably want to use a DailyRollingFileAppender. To roll them hourly, for example, you'd use a DatePattern of '.'yyyy-MM-dd-HH. For a log4j.properties file:

log4j.appender.myAppender=org.apache.log4j.DailyRollingFileAppender
log4j.appender.myAppender.DatePattern='.'yyyy-MM-dd-HH
...

Or for your programmatic configuration:

DailyRollingFileAppender appender = new DailyRollingFileAppender();
appender.setDatePattern("'.'yyyy-MM-dd-HH");

Logger root = Logger.getRootLogger();
root.addAppender(appender);

Unfortunately, using a DailyRollingFileAppender means that you can't limit the file size - this could be problematic if you have tons of logs in the given rolled period.

To compress take a look to: compress-log4j-files