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OOP-4 Lookup hashmap

K. Tsang

Joined: Sep 13, 2007
Posts: 3130

I once done this assignment a while back and now trying to enhance it and stuff. But I found a potential problem with my implementation.

When the hashmap is created should the value be a "Thing" or "String" through the getDescription() method?
eg HashMap<Integer, String> hMap ... or HashMap<Integer,Thing> hMap ...
assuming I populate the hashmap like this:
hMap.put(1, new BookOnTape()); //<Integer,Thing>
hMap.put(1, new BookOnTape().getDescription()); //<Integer,String>

Another way of asking is once the hashmap is populated, should the Thing's serial number be the same as the hashmap key?


K. Tsang JavaRanch SCJP5 SCJD OCPJP7 OCPWCD5 OCPBCD5 OCPWSD5 OCMJEA5 part 1 part 2/3
Marilyn de Queiroz

Joined: Jul 22, 2000
Posts: 9059
The value should be a Thing.

It is ok if the Thing's serial number is the same as the hashmap key, but the value should be the Thing, not the Thing's description.

"Yesterday is history, tomorrow is a mystery, and today is a gift; that's why they call it the present." Eleanor Roosevelt
K. Tsang

Joined: Sep 13, 2007
Posts: 3130

Thanks Marilyn, I got the serial number same as hashmap key
I agree. Here's the link:
subject: OOP-4 Lookup hashmap
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