I'm having some trouble testing a KClass<T> ...

# getting-started

[bbaldino]

I'm having some trouble testing a KClass<T> for being an Enum, and then getting an equivalent to Class<T Extends Enum<T>> out of it. for example:

fun <T : Any>test(valueType: KClass<T>) {
    when (valueType) {
        Enum::class -> {
            // How to get 'x' to be Class<T> where T extends Enum<T> ?
            val x = valueType.java
        }
        else -> TODO()
    }
}

[bbaldino]

val x = valueType.java as Class<Enum> complains about the missing type argument for Enum

[bbaldino]

valueType.java as Class<Enum<T>> complains because it doesn't see T as within the required bounds

[tseisel]

fun <T : Enum<T>> test(valueType: KClass<T>)

is the equivalent of

void <T extends Enum<T>> test(Class<T> valueType)

[bbaldino]

in my situation i'm unable to change the boundary on T...is there a way to force cast it?

[bbaldino]

(my real method must handle other values of T that aren't enums)

[bbaldino]

i figured there must be a way to force cast in the case i detect it as an enum, though, just haven't been able to sort out how to do it

[Daniel Seemaier]

does valueType.java as Class<Enum<*>> work?

[bbaldino]

it gets "closer", but still isn't what i need. i think i'll have to add more detail for my use case:

[bbaldino]

i have a generic method which takes in a value type KClass<T> and then, based on that type, returns an appropriate "getter" function which handles that type:

[bbaldino]

override fun <T : Any> getterFor(valueType: KClass<T>): (String) -> T {
        return when(valueType) {
            Boolean::class -> { path -> config.getBoolean(path) as T }
            Number::class -> { path -> config.getNumber(path) as T }
            Int::class -> { path -> config.getInt(path) as T }
            Long::class -> { path -> config.getLong(path) as T }
            Double::class -> { path -> config.getDouble(path) as T }
            String::class -> { path -> config.getString(path) as T }
            Enum::class -> { path ->
                val c = valueType.java as Class<Enum<*>>
                config.getEnum(c, path) as T
            }

[bbaldino]

the getEnum method i'm trying to call has the following signature:

[bbaldino]

public <T extends Enum<T>> T getEnum(Class<T> enumClass, String path);

[bbaldino]

when i use val c = valueType.java as Class<Enum<*>> i get this error:

[bbaldino]

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