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How to check duplicates in hashmap

 
vin Hari
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Hello all,
Iam using multimap to store duplicates ,for each key multiple values,
but how to retrive it means how to check for duplicate values while retrieving.please tell me how to check duplicate values.
 
David O'Meara
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The keys for a HashMap are stored in a Set - it won't allow duplicates. Either way, you can use the containsKey or containsValue method to look for anexisting record before insertion.
 
Nicholas Jordan
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This is an intermediate question, probably, but strikes me as belonging in advanced because complexity is involved.

MultiMap maps a key to a List or Vector which would mean that you would call get Iterator on the the return from a key lookup. You would then have to walk the value with the iterator, counting and testing and so on. I don't see where an Iterator is going to give out a count(), accessing the list or vector before walking the iterator would tell how many elements are in the List or Vector
 
vin Hari
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Thank you,
For reply, but iam not checking for duplicates while inserting,Actually what iam trying is iam creating menu driven program for which it requires for single submenu can contain many many elements thats why iam using multi map to insert but while retriving there values i want to check if next key is similar to previous key then make it as submenu and take out only values which form a items of submenu for that i require to see for duplicates even i tried with hashcode() but i did not get,
any more solutions please.
 
Stan James
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Can you show us a little code that almost works? Then we can tell exactly where you're stuck.

Is there something like this?
 
I agree. Here's the link: http://aspose.com/file-tools
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