Re: How can I get the key for a specified value in a HashTable object?
George wrote:
On Thu, 12 Jul 2007 Lekeas GK wrote...
|From: Flo 'Irian' Schaetz <iryan@gmx.de>
|Date: Thu, 12 Jul 2007 15:55:49 +0200
|Subject: Re: How can I get the key for a specified value in a HashTable
| object?
|
|And thus spoke George...
|
|> I am having the following problem: I have a HashTable object and I would
|> like to extract the value for a specified key - the opposite is easy to do
|> with the get method, but extracting keys from values does not seem to be
|> an easy process. Any ideas?
|
|That's not a good idea normaly - a HashTable is supposed to work the
|other way round... But of course you can simple iterate through the
|HashTable.keys() and see if one of them brings the correct value.
True, but this is not a very good idea when it comes down to searching
large hash tables. Is there any other data structure where there is no
key/value differentiation and you can search in both directions? I need to
be able to do that for the implementation of my PhD model and I have no
idea how to go about it.
Why not just build a two-way map using two HashMap instances, with the
key and value roles reversed between the two maps?
Patricia
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