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From: Jeff Higgins <jeff@invalid.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: LinkedHashMap - get latest key?
Date: Wed, 02 Apr 2014 12:06:24 -0400
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On 04/02/2014 10:44 AM, Andreas Leitgeb wrote:
> Given a LinkedHashMap instance, what would be a
> reasonable way to obtain the latest added key?
>
> The specific definition of "reasonable" being:
>   - no separate keeping track of key-sequence
>   - it should be a O(1) operation, and not
>      have to iterate all keys.
>
> Unlike TreeMap, the LinkedHashMap doesn't implement
> NavigableMap.
>
> If nothing else helps, I'll need to switch to a LinkedList,
> and thereby sell the "O(1)" of searching for an Object (by
> key) in exchange for a "O(1)" of obtaining the last Object.
>
> It just seems odd to me, that a LinkedHashMap doesn't
> have such a nobrainer getter, or, that a LinkedHashMap
> isn't also a NavigableMap with the natural ordering
> induced by position.
>
?
Collections.max(myMap.entrySet())