generics - Kotlin将类转换为Unit

Question

如何将通用类强制转换为Unit？

resultType is Unit

private fun <R : Any> Deferrable<R>.resolve(result: String?, resultType: Class<R>) {
        when  {
            resultType is Unit -> send(Unit)
            null -> throw NullPointerException("result is expected to be of type ${resultType}")
            else -> send(Json.parse(result, resultType))
        }
    }

Answer 1

所以，我找到了解决方案

@Suppress("UNCHECKED_CAST")
private fun <R : Any> Deferrable<R>.resolve(result: String?, resultType: Class<R>) {
    when {
        resultType.isInstance(Unit) -> send(Unit as R)
        result == null -> throw NullPointerException("result is expected to be of type $resultType")
        else -> send(Json.parse(result, resultType))
    }
}