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From: Martin Gregorie <martin@address-in-sig.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: Inserting In a List
Date: Tue, 2 Apr 2013 22:52:20 +0000 (UTC)
Organization: UK Free Software Network
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On Tue, 02 Apr 2013 18:22:55 -0400, Eric Sosman wrote:

> On 4/2/2013 5:06 PM, Martin Gregorie wrote:
>>[...]
>> Its also not clear to me whether the OP is expecting some form of
>> sorted list of filenames. If he is expecting that, it would be best to
>> use a TreeMap<String> rather than an ArrayList<String> to store the
>> filenames.
> 
>      Is there a reason to prefer TreeMap (or other SortedMap) over
> accumulate-disordered-and-sort-afterward?
>
I think so, yes, because none of File's list() and listFiles() methods 
guarantee the order of the returned files. By using TreeMap or equivalent 
the OP gets the sort for free, should it be required.

I use it a lot, both for that and because accessing stored objects by key 
from a TreeMap is almost certainly faster than scanning an ArrayMap 
unless it contains very few objects indeed. 


-- 
martin@   | Martin Gregorie
gregorie. | Essex, UK
org       |