java: (String[])List.toArray() gives ClassCastException

by

This is because when you use

 toArray()

it returns an Object[], which can’t be cast to a String[] (even tho the contents are Strings) This is because the toArray method only gets a 

List

and not 

List<String>

as generics are a source code only thing, and not available at runtime and so it can’t determine what type of array to create.

use

toArray(new String[v2.size()]);

which allocates the right kind of array (String[] and of the right size)

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