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convert a ArrayList to a Hashmap

jaggernat
jaggernat asked
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Last Modified: 2008-02-01
hi experts

i have a requirment where i have to convert a ArrayList to a Hashmap

want to know if thats possible

here is a code snippet
ArrayList judgeObjects = (ArrayList)request.getAttribute("judges"); //judges is of type list
Iterator judgeIterator=  judgeObjects.iterator();
while (judgeIterator.hasNext ()) {
    HashMap judegenames = judgeIterator.next(); //want to save ArrayList objects in Hashmap.// Any ideas ?....

....
}
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try this:

Map map = new HashMap();
ArrayList judgeObjects = (ArrayList)request.getAttribute("judges");Iterator judgeIterator=  judgeObjects.iterator();
while (judgeIterator.hasNext ()) {
    HashMap judegenames = judgeIterator.next(); //want to save ArrayList objects in Hashmap.// Any ideas ?....
    map.putAll(judegenames);
....
}

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Author

Commented:
works ..thanks.

one general question.

is ther any specific use of Hashmap over arraylist or vice-versa.
Can i just use Arraylist instead of using Hashmap in while loop
 (  HashMap judegenames = judgeIterator.next();
    map.putAll(judegenames);
 )
> is ther any specific use of Hashmap over arraylist or vice-versa.
HashMap (or Map in general) is used to store key - value pairs whereas List stores list of objects
> Can i just use Arraylist instead of using Hashmap in while loop
Well depends on the usage, if you want only either key or values of the judegenames, then you can use ArrayList
otherwise Map should be used

Author

Commented:
while (judgeIterator.hasNext ()) {
    HashMap judegenames = judgeIterator.next(); //want to save ArrayList objects in Hashmap.// Any ideas ?....
    map.putAll(judegenames);
....
}



for the above code , can i just use arraylist instead of hashmap. which one is a better choice

thanks
> for the above code , can i just use arraylist instead of hashmap. which
> one is a better choice
see above

Author

Commented:
thanks
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