Express intersection A&B in Java

[zhong...@gmail.com]

http://stackoverflow.com/q/32657561/2158288

If a method needs to accept an A&B argument, java has a very nice solution

    <T extends A&B> void f(T arg)

However, in other places where we need to express A&B, we might need a wrapper type. The OP asked for

    Class<? extends A&B>    ( & not allowed in wildcard bound (but why?) )

and I think I got a pretty nice solution with a wrapper type.

    Klass<? extends A, B>    

Zhong Yu
bayou.io

[y s]

Wouldn't you be able to do something like:

    <T extends A&B> Class<T> ... ?

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[zhong...@gmail.com]

On Friday, September 18, 2015 at 3:15:04 PM UTC-5, Yuval Shavit wrote:

Wouldn't you be able to do something like:

    <T extends A&B> Class<T> ... ?

I guess not in OP's case. He probably wants an instance variable in a non-generic class.

It is common that we use types like `Class<? exends Foo>`; then sometimes we may as well need `Class<? extends Foo&Bar>` ... but we can't express that directly.

Zhong Yu
bayou.io