| James J. Gavan 2006-03-09, 6:55 pm |
| Oliver Wong wrote:
Hey I have looked at rudimentaries - I knew Map = Dictionary :-)
Now I understand your 'Pairs' concept, your examples of 'doubles',
'triples' etc., that would work in the M/F dictionary class; and the J4
proposed KeyedCollection.
Mind you - if you think about it, the most logical thing is to have
names/descriptors as Dictionary Keys. I can't see you get much mileage
asking a dictionary "Do you have an element with a Key '12345' ?
There are several methods which pick up on the data, but I have never
used them.
One possibility - use a callback/iterator against the whole collection
automatically checking each element. Then terminate with
'quitIteration', when you have found what you want.
My prime interest was converting data files written in RM/COBOL to
either M/F Files or SQL Tables. As part of 'normalization' I wanted to
get rid of duplicate descriptors stored in 700 data sets, (very small
volumes each, 20 - 30 entries). Example :
Gas Plant A - System 123 - Gas Scrubber
Gas Plant B - System 456 - Gas Scrubber
Using mnemonic codes in the DB Table, GS = Gas Scrubber - build
Dictionary from existing codes in the DB Table and as I read in each RM
entry do a look-up : (1) If found use new "GS" code, or (2) add a new
code to the Dictionary and write it to the DB Table - the M/F
files/Tables written for Plants A and B above contain the new mnemonics.
TOP POST - no more
Jimmy
>
> "James J. Gavan" <jgavandeletethis@shaw.ca> wrote in message
> news:uJNPf.128728$B94.114109@pd7tw3no...
>
>
>
> Yes, I meant something different.
>
> In Java as well, you can't have a dictionary (though it's called a
> "Map" in Java) where two objects have the same key. I was saying you
> could "fake" it by having a "Pair" object whose sole purpose is to
> contain references to the two objects you *do* want to store.
>
> Key --> Data
> 123 (Hot, Cold)
> 124 (push, pull)
> 125 (stop, go)
> etc.
>
> The idea is that only one object, the "pair" object, is associate with a
> given key. But the pair object is like a collection whose size is
> guaranteed to always be 2. Obviously, you can extend this idea if you
> wanted to simulate 3 objects per key:
>
> Key --> Data
> 123 (Hot, Warm, Cold)
> 124 (push, rest, pull)
> 125 (red, green, blue)
> etc.
>
> - Oliver
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