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Forced types in java property declaration

Java Code:

class First {}
class Second extends First {}
class Jinkies<T> {}
interface Greeting<T> {}
class Hello<U extends T, T> implements Greeting<T> {
  private Map<Jinkies<U>, List<U>> scooby;
}

In the announcement scooby, both Jinkiesand Listhave the same type parameter - this is what I want to provide. Is there a way to do this in Java, without the transfer of the two parameters ( Uand T) in the class declaration Hello?

I would like to have only one - for example. sort of:

class Hello<U extends T> implements Greeting<T>

however, this does not compile. I have to write:

new Hello<Second, First>()

instead:

new Hello<Second>()

although I don’t care Firstanywhere in the body Hello(as well as users Hello).

Edit - as @LouisWasserman explains in the comment, the bad example on my part is above. Maybe clarify - let's say I always want to do:

new Hello<First>()

U, U extends First (.. First Second ) Hello, First , U . , :

void method1(U a) {}
void method2(U b) {}

, U U , not , (.. First Second), .

<U extends T> void method1(U a) {}
<U extends T> void method2(U b) {}

, method1(first) method2(second).

- , , , -. , . , First, "" Third. Second, "" Zero. ...

+4
1

, , , :

class Jinkies<X> {}
interface Greeting<Y> {}
class Hello<T,U extends T> implements Greeting<T> {
  private Map<Jinkies<U>, List<U>> scooby;
}

, T new Hello<Second, First>(), , T.

+2

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