Re: Evaluating FileAlterationMonitor

BTW, what are your findings that make WatchSerice not work well?

Gary


On Tue, Jan 30, 2024, 11:57 AM Gary D. Gregory <[email protected]> wrote:

> Patrick,
>
> ATM, I think you could create a subclass of the FileAlterationObserver and
> re-implement FileAlterationObserver.checkAndNotify(). You'll have to decide
> what to do in the case of file trees. Do you want to sort by timestamp for
> all files in the tree or just sort files in the current folder being
> processed. At least, that's the consideration needed for a general
> solution. You'll notice that any solution will likely need a second file
> comparator that sorts files for presentation to listeners in the customized
> order. The current comparator is needed as is since it is used for event
> and event type detection.
>
> Let me know what you think and you are considering providing a PR on
> GitHub.
>
> TY!
>
> Gary
>
> On 2024/01/29 23:15:17 Gary Gregory wrote:
> > YW. I think you could sort files if I refactor the monitor a bit such
> that
> > you can plug in a custom comparator (it's already there internally)...
> >
> > Gary
> >
> > On Mon, Jan 29, 2024, 5:19 PM Thomas, Patrick R
> > <[email protected]> wrote:
> >
> > > Thanks for the quick response. I will need to test its behavior for
> lost
> > > connections.
> > >
> > > Based on what I have discovered so far, I will have to create my own
> > > monitor. I need to create a list of new files from all of the monitored
> > > folders during each pass and then sort them by date/time to make sure
> they
> > > are processed in the correct order.
> > >
> > > It doesn't seem to notify about files that already exist. I will have
> to
> > > add this as well, although it is optional because it doesn't work
> correctly
> > > in my current system.
> > >
> > > Thank you,
> > >
> > > Patrick R. Thomas
> > >
> > > -----Original Message-----
> > > From: Gary Gregory <[email protected]>
> > > Sent: Monday, January 29, 2024 2:05 PM
> > > To: Commons Users List <[email protected]>
> > > Subject: Re: Evaluating FileAlterationMonitor
> > >
> > > CAUTION! This email originated outside of Quest Diagnostics. DO NOT
> click
> > > links or open attachments unless you recognize the sender and know the
> > > content is safe. Please report suspicious emails to:
> > > [email protected]
> > >
> > >
> > > The documentation we have is on the site and the Java document. If you
> > > have improvements on the code or documentation, we welcome them as PRs
> on
> > > GitHub.
> > >
> > > The monitor thread wakes up, looks around, and fires events. If a file
> is
> > > not there because a network connection is broken, this will show up as
> a
> > > deleted file.
> > >
> > > YYMV since we do not test this use case in unit tests.
> > >
> > > Gary
> > >
> > >
> > > On Mon, Jan 29, 2024, 1:45 PM Thomas, Patrick R
> > > <[email protected]> wrote:
> > >
> > > > Hello,
> > > >
> > > > Our application monitors multiple folders for new files to import.
> > > > Once a new file is detected, it is moved to a working folder where it
> > > > is processed and then moved to an archive folder. Files are never
> > > > updated, and ones that are deleted before processing are skipped. The
> > > > current implementation has the folders on the same server as the
> > > > application. We are using Java's WatchService to do the monitoring.
> > > > For security reasons, we have to move to a new design where the
> > > > folders will be on a different server. My understanding is that
> > > > WatchService will not work well for this. I am evaluating
> > > > FileAlterationMonitor as an alternative. I have several questions. Is
> > > > there additional documentation I can reference? If the folder being
> > > > monitored is on a mapped network drive and the connection is lost,
> > > > what happens? Can the monitor detect files that already exist when it
> > > > starts? It is also important that the files remain in the order they
> > > were created to be imported.
> > > >
> > > > Any help would be greatly appreciated.
> > > >
> > > > Thank you,
> > > >
> > > > Patrick R. Thomas
> > > > Software Engineer
> > > >
> > > >
> > > >
> ______________________________________________________________________
> > > > The contents of this message, together with any attachments, are
> > > > intended only for the use of the person(s) to which they are
> addressed
> > > > and may contain confidential and/or privileged information. Further,
> > > > any medical information herein is confidential and protected by law.
> > > > It is unlawful for unauthorized persons to use, review, copy,
> > > > disclose, or disseminate confidential medical information. If you are
> > > > not the intended recipient, immediately advise the sender and delete
> > > this message and any attachments.
> > > > Any distribution, or copying of this message, or any attachment, is
> > > > prohibited.
> > >
> > > ______________________________________________________________________
> > > The contents of this message, together with any attachments, are
> intended
> > > only for the use of the person(s) to which they are addressed and may
> > > contain confidential and/or privileged information. Further, any
> medical
> > > information herein is confidential and protected by law. It is
> unlawful for
> > > unauthorized persons to use, review, copy, disclose, or disseminate
> > > confidential medical information. If you are not the intended
> recipient,
> > > immediately advise the sender and delete this message and any
> attachments.
> > > Any distribution, or copying of this message, or any attachment, is
> > > prohibited.
> > >
> >
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [email protected]
> For additional commands, e-mail: [email protected]
>
>