First some backstory:
I have a special need to allow the use of a common/shared log file within a clustered environment. I have already taken other measures necessary to handle the simultaneous writing of logging events to the same file w/o corruption. I have been using log4j 1.2.x for a while for this purpose, and it's been working in a production environment for quite some time actually.
What I did there is make my own DailyRollingSharedFileAppender (based on the old DailyRollingFileAppender) that contains some custom logic & locking to provide a safe mechanism for handling file rollovers on the shared files.
I am currently in the process of upgrading to log4j2 for several reasons, and as such am working to re-implement this concept by making a couple of custom classes to augment log4j2 accordingly. Given the new architecture (which is very nice, BTW) I think this should actually a fairly straightforward process...
1) Create a SharedFileRenameAction that extends FileRenameAction (has my custom logic & locking)
2) Create a SharedFileRolloverStrategy that extends DefaultRolloverStrategy (no gz/zip support, uses SharedFileRenameAction)
3) Reference SharedFileRolloverStrategy in log4j2.xml for the appenders using shared files
So for this, I only need to override a few things in these classes, and as such I'd rather extend them than completely write new ones. For #2 this is not an issue, but for #1 I have hit a snag:
public final class FileRenameAction extends ActionBase
(note: using beta-2 here, in trunk ActionBase is now AbstractAction)
I've marked this issue as "Question" for now, so here is that question:
Why is FileRenameAction marked final?
If there was no intentional restriction on extensibility here, then I'd like to make this issue an "Improvement" instead, requesting that this class no longer have the final qualifier.