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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 16:00:42 -0700
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Wojtek <nowhere@a.com> writes:

> Using:
>
> int max = 10;
> int count = 0;
>
> for (File thisFile : aDir.listFiles())
> {
>  doSomething(thisFile);
>
>  if ( ++count >= max )
>    break;
> }
>
> gives me the first ten files in aDir. But if aDir contains 30K files,
> then the listFiles() will run for a long time as it builds an array
> for the 30K files.
>
> Is there a way to have Java only get the first "max" files?

As Roedy says, in pure Java there's no way to avoid reading the entire
directory, whether it builds the entire array or not.  And if you want
them in any particular order it's necessary to read them all and sort
them anyway.

-- 
Jim Janney