Re: Java 5 Generics Question

Steven <steven.green30@xxxxxxxxxxx> writes:

> I am trying to define an array of vectors.
> For example:
>
> Vector<Object>[] data = new Vector[4];
>
> The preceeding works with warnings.
> Trying:
>
> Vector<Object>[] data = new Vector<Object>[4];
>
> Fails with errors.
> What is the proper way to define an array of Vector<Object> ?

You cannot (in Java 5.0). The reason is that there's no way the array
element assignment check at data[i] = ... could be performed, because
there is no runtime representation of the array element type
Vector<Object>.

Instead use array lists, as in:

ArrayList<Vector<Object>> data = new ArrayList<Vector<Object>>();

WARNING: Technical information, not flame bait, ahead:

This is one of the things that work a little better in
C#/CLI 2.0: the runtime supports exact type instances of generic
types, and therefore you can create an array whose element type is a
type instance of a generic type.

Peter
--
Department of Natural Sciences http://www.dina.kvl.dk/~sestoft/
Royal Veterinary and Agricultural University * Tel +45 3528 2334
Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark * Fax +45 3528 2350
.

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