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From: Jim Janney <jjanney@shell.xmission.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: The first 10 files
Date: Sat, 26 Jan 2013 17:13:19 -0700
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Wojtek <nowhere@a.com> writes:

> John B. Matthews wrote :
>> Although it may be beyond your control, you should also critically
>> assess a design having tens of thousands of files in a single
>> directory.
>
> Well of course.
>
> The directory holds files which are uploaded by external events. If
> there are a lot of events between application runs, then the number of
> files can indeed reach large numbers.
>
> Since this is happening on a server, and you cam potentially have many
> hundreds of people accessing at the same time (each with there own
> directory), I was hoping to be able to "stage" file processing.
>
> The:
>
> public boolean accept(File pathname) {
>             return maxFiles-- > 0;
>         }
>
> in FileFilter is interesting, but the file system nevertheless still
> runs through the entire directory. Maybe FileFilter needs:
>
> public boolean abort(File pathname);
>
> Hmm, maybe I need a timed background process to move files to
> "holding" directories which will be limited to a small number of
> files.

You could run a command in a subprocess.  On a Unix system

    ls -U | head -n 10

should run quickly (-U tells it not to sort).  Not sure how to do that
on Windows.

-- 
Jim Janney