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ArrayList to HashMap

S Majumder
Ranch Hand

Joined: Jun 03, 2009
Posts: 244
Hi everybody ,
Is there any java methods available by which I can take the ArrayList values and put into the HashMap's key or value ?

I am giving one example here :



I know I can do it by iterating the myList into loop & get those values & put into myMap.

Thanks

S
Campbell Ritchie
Sheriff

Joined: Oct 13, 2005
Posts: 39478
    
  28
It is quite easy to put keys or values into a Map, but you need to put them in pairs. If your elements from the Map go as Keys, what would you use as Values? If your elements from the Map go as Values, what would you use as Keys?
Rob Spoor
Sheriff

Joined: Oct 27, 2005
Posts: 19725
    
  20

Nope, that's the only one. The reason is the completely different structure of List (and Set, Collection, Queue, etc - all flat sequence structures) versus Map (key-to-value mapping).


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