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Author

Help with Data Structures...

Sneha Kashyap
Greenhorn

Joined: May 06, 2009
Posts: 22
Hi,

I am unable to decide as to which data structure to use for the following purpose
Slno Name
01 abc
01 def
02 abc
03 xyz

I want these to be grouped and then stored accordingly Like: 01 {abc,def}
02 {abc}
03 {xyz}
I want to group these as itemsets based on the sl no value.

Please Help Thanks in advance.
mahesh shinde
Ranch Hand

Joined: Jul 24, 2009
Posts: 69

you mean which collection class
Sneha Kashyap
Greenhorn

Joined: May 06, 2009
Posts: 22
Thanks, Yeah and how to use it to achieve the same.
Ulf Dittmer
Rancher

Joined: Mar 22, 2005
Posts: 42958
    
  73
How about Map<Integer, List<String>>?

Or maybe Map<String, List<String>> if the "01" is a string and not an integer.
Sneha Kashyap
Greenhorn

Joined: May 06, 2009
Posts: 22
Thanks, but map cannot contain duplicate values, I need to have duplicate keys, like 01 mapping to abc,def Can you help me as to how this can be achieved.
saipraneeth nallapareddy
Ranch Hand

Joined: Dec 02, 2009
Posts: 159
i guess it is TreeSet which will eliminate the duplicate not the HashMap.
name-value pairs are sufficient.
don't confuse with HashSet and HashMap.
Ulf Dittmer
Rancher

Joined: Mar 22, 2005
Posts: 42958
    
  73
Thanks, but map cannot contain duplicate values, I need to have duplicate keys, like 01 mapping to abc,def

That's not duplicate keys in the Map, that's multiple entries in the List.
Campbell Ritchie
Sheriff

Joined: Oct 13, 2005
Posts: 44031
    
  33
Sneha Kashyap wrote: Thanks, but map cannot contain duplicate values, I need to have duplicate keys, like 01 mapping to abc,def Can you help me as to how this can be achieved.
Ulf has already told you what to do.
 
Have you checked out Aspose?
 
subject: Help with Data Structures...
 
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