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dynamic Array (ArrayList)

Anthony Smith
Ranch Hand

Joined: Sep 10, 2001
Posts: 285
I needed a dynamic array so I did an ArrayList. My actual method needs to return a int array. SO in order to do that do I have to declare an in array of the size of my ArrayList and then get each element out convert it to an int and then put it into my int array or is there a way I can do it in one shot w/o a loop?
Bert Bates

Joined: Oct 14, 2002
Posts: 8898
Anthony -
You can get part way there by calling the toArray( ) method, that'll get you an array of Objects...

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Jim Yingst

Joined: Jan 30, 2000
Posts: 18671
Or, assuming your ArrayList contains Integer objects, you can get a tiny bit further with

This way you have an Integer[] rather than an Object[]. But still, if what you really wanted was an int[], you need a loop. And as long as you have to do that anyway, you might as well forget the toArray() stuff and build the array you want directly:

It would be nice if there were a one-liner for this, but it's not that big a deal really...

"I'm not back." - Bill Harding, Twister
I agree. Here's the link:
subject: dynamic Array (ArrayList)
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