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Subject: Re: Question about HashMap and Map.Entry ...
Date: Thu, 30 Aug 2012 10:46:57 -0700
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On 8/30/2012 10:39 AM, Andreas Leitgeb wrote:

> What I'm missing, however, is:
>    How would I get the Entry for a given key?


What about:

   Long value = hashMap.get( key );
   if( value != null )
     hashMap.put( key , newValue );

This only updates the value for key if key is already present.  I think 
that's what you said you are doing.  It assumes that "null" is not a 
valid value for any key.  (That can be changed as well, but it's 
basically a scan through the entries at that point.)