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List<String> toArray problem

I have:

 List<String> myStringList = new ArrayList<String>();

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then later:

myStringList.add(myString);

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then even later:

return (String[]) myStringList.toArray();

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which caues the exception:
java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to [Ljava.lang.String;

I've referred to nothing but String in myStringList, yet it think it is list of Object.
What gives?

SOLUTION

for_yan

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SOLUTION

CPColin

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ASKER CERTIFIED SOLUTION

CEHJ

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CEHJ

Mick Barry

> The following is better. Otherwise (iirc) the array gets created twice

It doesn't get created twice
What CPColin suggested is the recommended approach

CEHJ

>>It doesn't get created twice

That's incorrect

CPColin

"It" isn't created twice, but two arrays are. The array passed in is created and the array returned is created. My suggestion is shorter, at the expense of the one extra initialization; CEHJ's is slightly more efficient, at the expense of a few more characters of code (although the cast shouldn't be necessary).

CEHJ

>>"It" isn't created twice, but two arrays are.

Yes, that's what i meant

Mick Barry

> at the expense of the one extra initialization

which is so small its not worth worrying about

> (although the cast shouldn't be necessary).

its not

CEHJ

>>(although the cast shouldn't be necessary).

You're right - old habits die hard ;)

CEHJ

>>which is so small its not worth worrying about

How would you know how small that, created by reflection, would be?

List&lt;String&gt; toArray problem

List<String> toArray problem