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Re: Question about HashMap and Map.Entry ...

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Daniel Pitts <newsgroup.nospam@virtualinfinity.net> wrote:
> On 8/30/12 12:32 PM, Andreas Leitgeb wrote:
>> Damn, on re-read, I notice, that my own implementation of
>> Map.Entry could just hold a ref to the map and implement
>> setValue() to write the value back into the Map...
> Or, if you know all the keys before hand, you can use instead Map<Long, 
> MyLongWrapper> map.

I know all the relevant keys before hand. I currently do
an initial map.put(k,0L) for each relevant "k".

> MyLongWrapper would have .set() and .get(), or even .actUpon()
> depending on the semantics you need.

Indeed, that is a more elegant approach, than mine.
Although it won't save me the extra containsKey(), as I'll
be also having "k"s that aren't in the map, I'll turn my
auxiliary Entry-taking method from the outer class into a
method of some inner class MyLongWrapper that only needs
the extra "v" as parameter...

> Again, I suggest Trove, I seem to recall they had an interface that 
> supported exactly what you are trying to accomplish.

Yep, they seem to have inspired your suggestion, but now
that I know it, I don't actually need TLong*HashMap 
anymore. (My processing on the values is none of these
trove-predefined ones, anyway)

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Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 17:39 +0000
  Re: Question about HashMap and Map.Entry ... markspace <-@.> - 2012-08-30 10:46 -0700
    Re: Question about HashMap and Map.Entry ... Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-30 11:15 -0700
      Re: Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 19:24 +0000
        Re: Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 19:32 +0000
          Re: Question about HashMap and Map.Entry ... Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-30 13:08 -0700
            Re: Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 21:55 +0000
              Re: Question about HashMap and Map.Entry ... Robert Klemme <shortcutter@googlemail.com> - 2012-08-31 07:27 +0200
                Re: Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-31 10:26 +0000
                Re: Question about HashMap and Map.Entry ... Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-08-31 11:22 -0700
                Re: Question about HashMap and Map.Entry ... Robert Klemme <shortcutter@googlemail.com> - 2012-09-01 11:06 +0200
        Re: Question about HashMap and Map.Entry ... markspace <-@.> - 2012-08-30 14:30 -0700
          Re: Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 22:42 +0000
        Re: Question about HashMap and Map.Entry ... markspace <-@.> - 2012-08-30 14:34 -0700
  Re: Question about HashMap and Map.Entry ... Lew <lewbloch@gmail.com> - 2012-08-30 13:42 -0700
    Re: Question about HashMap and Map.Entry ... Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-08-30 22:34 +0000

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