File APIs for Java Developers
Manipulate DOC, XLS, PPT, PDF and many others from your application.
The moose likes Cattle Drive and the fly likes OOP-4 Lookup hashmap Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login
JavaRanch » Java Forums » This Site » Cattle Drive
Bookmark "OOP-4 Lookup hashmap" Watch "OOP-4 Lookup hashmap" New topic

OOP-4 Lookup hashmap

K. Tsang

Joined: Sep 13, 2007
Posts: 1966

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?


Marilyn de Queiroz

Joined: Jul 22, 2000
Posts: 9043
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: 1966

Thanks Marilyn, I got the serial number same as hashmap key
wood burning stoves
subject: OOP-4 Lookup hashmap
Similar Threads
Collections how much detail??
Extract HashMap array value
static objects
Storing objects in hashmap