Generic Generics: "Syntax error on token "extends", , expected"

Question

``` public interface View{... public interface Control{... public class RemoteControl> implements Control{... ``` gives me a "Syntax error on token "extends", , expected" on "V extends View" for the RemoteControl class. I guess the following alternative was possible ``` public class RemoteControl,V extends View> implements Control {... ``` Still I wonder if this cannot be done in a more implicit way since the latter would require a redundant declaration of the View. I.e.: ``` public class TVRemoteControl extends RemoteControl implements TVControl{... ``` vs ``` public class TVRemoteControl extends RemoteControl implements TVControl{... ``` Maybe I'm just stuck in a box again, but is it possible to get the "generic Generics" in a more elegant way

Accepted Answer

You suggest: I guess the following alternative was possible ``` public class RemoteControl,V extends View> implements Control{} ``` This is the correct solution, although I would normally write it as (for readability): ``` public class RemoteControl> implements Control{} ``` You are typing `RemoteControl` on a `Control` object which is also typed on an object that `extends View`. As such you need to provide the implementation of `View` that types the `Control` object that types your `RemoteControl` object. I guess you could interpret your question as saying, why do I have to provide `V` - shouldn't it be implied from the `>`. To which, the answer is no, you need to provide a type for `V` to ensure that the right type of `Control` is provided (i.e. that it `extends Control`) If you don't care what type `View` the `Control` object is typed on, you don't need to type `Control` in the `RemoteControl`: ``` public class RemoteControl implements Control{} ``` However, the fact `Control` is typed on `V extends View` and `RemoteControl implements Control`, rather suggests that you do...

Generic Generics: "Syntax error on token "extends", , expected"

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