Converting generic ArrayList

Question

Is it possible to convert:

ArrayList<?> objects; to ArrayList<String>() if you know objects only contains Strings?

SLaks · Accepted Answer · 2013-12-03 15:56:35Z

7

Yes; just cast it.
You will get a compile-time warning, because even though you know that, the compiler doesn't.

Beware that if someone else adds some other class to the list after you cast it, you will get exceptions when you try to use it.

This is only true because of type erasure.

answered Dec 3, 2013 at 15:56

SLaks

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Comments

Tourki · Accepted Answer · 2013-12-03 15:57:32Z

2

ArrayList<?> anonymList = null;
ArrayList<String> strings = (ArrayList<String>) anonymList;

answered Dec 3, 2013 at 15:57

Tourki

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