Kotlin：按类生成工厂

我们正在尝试在kotlin中进行一些通用处理。基本上，对于给定的类，我们希望获得相关的生成器对象。i、 a.对于任何扩展GenericObject的对象，我们需要该对象的生成器

interface Builder<T : GenericObject> 
object ConcreteBuilder: Builder<ConcreteObject>

然后我们可以通过以下方式获得：

inline fun <reified T : GenericObject> transform(...): T {
    val builder = map[T::class] as Builder<T>
    ...

inline fun转换（…）：T{
val builder=将[T:：class]映射为生成器
...

但是这不是很好，因为：

• 我们需要显式转换到

  Builder

• 映射没有

  T

  的概念，键和值可能与不同的类型相关

---

有没有更好的方法来实现它？

地图的包装可以是：

class BuilderMap {

    private val map = mutableMapOf<KClass<out GenericObject>, Builder<out GenericObject>>()

    fun <T: GenericObject> put(key: KClass<T>, value: Builder<T>) {
        map[key] = value
    }
    
    operator fun <T: GenericObject> get(key: KClass<T>): Builder<T> {
        return map[key] as Builder<T>
    }
    
}

---

Thx它做得很好

class BuilderMap {

    private val map = mutableMapOf<KClass<out GenericObject>, Builder<out GenericObject>>()

    fun <T: GenericObject> put(key: KClass<T>, value: Builder<T>) {
        map[key] = value
    }
    
    operator fun <T: GenericObject> get(key: KClass<T>): Builder<T> {
        return map[key] as Builder<T>
    }
    
}

val builderMap = BuilderMap()
builderMap.put(ConcreteObject::class, ConcreteBuilder)
builderMap.put(BetonObject::class, BetonBuilder)
// builderMap.put(BetonObject::class, ConcreteBuilder) – will not compile

val builder = builderMap[T::class]