On 11/13/2012 07:08 AM, Alan Bateman wrote:
On 12/11/2012 23:22, Jim Gish wrote:
Which file(s) are you concerned about truncating/damaging? The code
I'm impacting is for creating a new lock file. Where is the
potential for truncating/damaging that you both are referring to?
Is this sufficient (plus the proper exception handling of course) ?
//lockStream = new FileOutputStream(lockFileName);
fc = FileChannel.open(new
File(lockFileName).toPath(), CREATE_NEW, WRITE);
//fc = lockStream.getChannel();
CREATE rather than CREATE_NEW so that it doesn't fail if the lock file
already exists. Although it's just a lock file then I think it would
be impolite to truncate it.
You could use Paths.get(lockFileName)rather than new
File(lockFileName).toPath() here but either is fine.
-Alan.
I think we want it to fail if the lock file already exists. That's why
I used CREATE_NEW. At least the way the logic is now, is that it
attempts to create a new file and if it fails it tries again until it
can create a new one. It may be the case that the lockFileName is not
in the locks map, and thus we don't own it, but it's possible that
another JVM/app is logging in the same location. It, of course, would be
bad practice, but not disallowed. We shouldn't be grabbing a lock file
that might otherwise be in use.
Jim
--
Jim Gish | Consulting Member of Technical Staff | +1.781.442.0304
Oracle Java Platform Group | Core Libraries Team
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