Map -> Arraylist

[Pockets]

Is there a method out there to strip out the keys to a Map and return an ArrayList of all the elements? In the context here, the keys are unimportant and can be discarded.

[DemonWasp]

Without speaking to any kind of efficiency concern, you could use:

Java:

map.entrySet().toArray

to get an array. Array -> ArrayList is trivial too.

[OneOffDriveByPoster]

DemonWasp @ Mon Nov 10, 2008 9:51 am wrote:

Java:

map.entrySet().toArray

The above won't get you just the values of course. Anyhow, why do you need the conversion? Do you have methods you need to call that need an ArrayList?

[Pockets]

Yeah, it's for a game of hearts. We're handed a trick as a map of <playerID strings, Card objects>, and I need to strip the card objects into a simple array for use in a card counting function. I may just use a manual iterator though.

[OneOffDriveByPoster]

Pockets @ Mon Nov 10, 2008 4:35 pm wrote:

I may just use a manual iterator though.

This is probably a cleanest thing to do. If you are not sure you will always have a Map, then use a Iterator from Map.values(). Not sure why you wanted an ArrayList specifically. Map.values() will give you a Collection view of the map's values. Your algorithm might not need to have something as specific as ArrayList.