Migrating to Java from C++.
I have a third party code with an interface I am required to implement which goes something like this.
public interface Foo<T>{
public T doSomething();
}
I want to implement this interface so that I can call doSomething() and get 3 different classes A, B and C which extend a common base Z as below.
public class A extends Z{...};
public class B extends Z{...};
public class C extends Z{...};
I could not find any way of avoiding writing the following 3 classes.
public class ARet implements Foo<A>{...}
public class BRet implements Foo<B>{...}
public class CRet implements Foo<C>{...}
For the given interface Foo, is it not possible to write an implementation which returns T extends Z something which would look like public class Ret implements Foo<T extends Z>{...}. This does not appear to work. Is there any way of avoiding the 3 classes or there is no way around it?
If you want the implementation of the interface to be generic, you need to declare T as a generic type parameter of Ret :
public class Ret<T extends Z> implements Foo<T>{...}
Collected from the Internet
Please contact [email protected] to delete if infringement.
Comments