Help with Data Structures...

[Sneha Kashyap]

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]

you mean which collection class

[Sneha Kashyap]

Thanks, Yeah and how to use it to achieve the same.

[Ulf Dittmer]

How about Map<Integer, List<String>>?

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

[Sneha Kashyap]

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]

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]

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]

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.