Combining bounded wildcards in Java

Question

Is there anyway to use a bounded wildcard require a class implement more than one interface?

In otherwords, something like...

class Foo<S extends Comparable && Clonable>

...which would require that objects extend both interfaces?

I realize I can make another ComparableAndClonable which extends the two but I don't have control over some of the code (So I can't go make my future-S object implement ComparableAndClonable).

For the record, `S` is a [bounded type parameter](https://docs.oracle.com/javase/tutorial/java/generics/bounded.html), not a [bounded wildcard](https://docs.oracle.com/javase/tutorial/java/generics/wildcards.html). — shmosel, Feb 18 '16 at 22:06

score 3 · Accepted Answer · edited May 23 '17 at 11:50

3

class Foo<S extends Comparable & Clonable>

Should work.

See Java Generics Wildcarding With Multiple Classes for further info.

[1]:

edited May 23 '17 at 11:50

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answered Mar 03 '10 at 18:03

Martin

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Combining bounded wildcards in Java

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