From: forgottenwizard <phrexianreaper@...>
Date: 2007-10-30T03:44:25+09:00
Subject: Re: Problem using FileUtils to sort JPEG files

On 14:54 Mon 29 Oct     , 7stud -- wrote:
> Suppose your directory has 2,000 files in it.
> 
> The way I see it, in order for your code to determine whether a file's 
> type is already a directory, your code has to go searching through a 
> directory with 2,000 files in it.  And your code does that for each 
> filename.  Also, if your directory has 10,000 files instead of 2,000 
> files, then the search will take five times as long.
> 
> The code I posted only has to search through the directory three times 
> to set things up, i.e when it creates the directories. After that, the 
> code loops over the file names and does a lookup in a hash to determine 
> if there's a directory for the file's file type, and hash lookups are 
> extremely fast.   Which would you rather do: search a directory 
> containing 2,000 files 2,000 times; or search a directory containing 
> 2,000 files 3 times, and then do extremely fast hash lookups 2,000 
> times?  For the purposes of the comparison, you can assume hash lookups 
> take 0 time.

Alright, I see what you are saying. I'll look over your code again,
since I obviously missed something.

Thanks for the explinasion :)