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OOP-4 Lookup hashmap

K. Tsang
Bartender

Joined: Sep 13, 2007
Posts: 2726
    
    9

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?

Thanks


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

Joined: Jul 22, 2000
Posts: 9055
    
  12
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.


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K. Tsang
Bartender

Joined: Sep 13, 2007
Posts: 2726
    
    9

Thanks Marilyn, I got the serial number same as hashmap key
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: OOP-4 Lookup hashmap