What purpose do generic constructors serve in Java?

Question

As everyone knows you can have a generic class in Java by using type arguments:

class Foo<T> {     T tee;     Foo(T tee) {         this.tee = tee;     } } 

But you can also have generic constructors, meaning constructors that explicitly receive their own generic type arguments, for example:

class Bar {     <U> Bar(U you) {         // Why!?     } } 

I'm struggling to understand the use case. What does this feature let me do?

Answer 1

The use case I'm thinking of might be that some wants an Object which inherits from 2 Types. E.g. implements 2 interfaces:

public class Foo {      public <T extends Bar & Baz> Foo(T barAndBaz){         barAndBaz.barMethod();         barAndBaz.bazMethod();     } } 

Though I have never used it in production.