Creating an array of generics in java

Asked Feb 05 '18 at 00:24

Active Feb 05 '18 at 01:02

Viewed 42 times

I have been out of touch with Java for a while and trying to create an array of generics and a bit confused.

For regular types I can do things like this:

 String s[] = new String[10];

However if I have my own data type say a bag of integers and I want to define an array of Bag why can't I do this:

 Bag<Integer> b[] = new Bag<Integer>[10];

Neither can I do this:

 Bag<Integer> b[] = (Bag<Integer>) new Object[10];

The above doesnt work, how do I fix it?

EDIT: I saw the "duplicate" answer before I posted but I am unable to figure out how to use information in that answer to solve my problem. I have boiled down my issue to the simplest form and it doesnt appear to be the same.

edited Feb 05 '18 at 01:02

asked Feb 05 '18 at 00:24

user2399453

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I get a generic array creation error. – user2399453 Feb 05 '18 at 00:27
you should give the definition of `Bag` – davidxxx Feb 05 '18 at 00:28
@davidxxx If you just need to test it, use `class Bag {}`. The full definition isn't necessary. – 4castle Feb 05 '18 at 00:36
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Generics are erased at runtime, but since array want to validate type of inserted elements at runtime it doesn't want to accept generics. Instead consider using `List>` – Pshemo Feb 05 '18 at 00:46

Creating an array of generics in java

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