Question about generics. Having this code: ```// ...

# stdlib

[Greg Rynkowski]

Question about generics.

Having this code:

// all T - java classes implementing ViewDataBinding, each providing a static `bind` method
// ViewDataBinding - a Java abstract class (with no declaration of `bind`)

interface BindingAware<T : ViewDataBinding> {
    var f: T

    fun bind(v: View) {
        // f = T.bind(a)  // <= how to call static method provided by class behind T?
    }
}

How to call static method of T, having only T?

[Ruckus]

implementing ViewDataBinding, each providing a static bind method

Unfortunately, that static method is not part of the interface definition, so there's no way for the compiler to resolve.

[Ruckus]

There's no way (that I'm aware of) to provide a generic T with any knowledge of the associated class statics. If all subclasses are known, you could use a lookup table, otherwise you'll likely need some reflection magic (or pass a reference to the static method in as a member of any implementation of BindingAware, but that seems to defeat the purpose).

[Greg Rynkowski]

no, all subclasses are not known

tbh I made a simple solution using the reflection

interface ViewBindingAware<T : ViewDataBinding> {
    var b: T
}

inline fun <reified T : ViewDataBinding> ViewBindingAware<T>.bindView(v: View): T {
    val bindMethod = T::class.java.getMethod("bind", View::class.java)
    b = bindMethod.invoke(null, v) as T
    return b
}

and it works but I don't like too much reflection-based solutions and I left it on a side for now