使用静态类型别名 Java 类 [英] Type aliasing Java classes with statics

问题描述

假设 MyClass 是一个用 Java 定义的类，并且有许多静态和非静态成员.我试图在 Scala 对象 MyObject 中为这个类(和相关联的对象)取别名，如下所示:

Suppose MyClass is a class defined in Java, and has many static as well as non-static members. I tried to alias this class (and associated companion object) in a Scala object MyObject as shown below:

object MyObject {
  import javastuff._
  type MyAlias = MyClass
  val MyAlias = MyClass
}

Scalac 抱怨:

error: object MyClass is not a value
val MyAlias = MyClass

我该如何解决这个问题?谢谢.

How do I work around this? Thanks.

推荐答案

虽然这在纯 Scala 中适用于类 + 伴生对象，但在 Java 的静态方法中是不可能的，因为这些不属于任何接口.

Although this works in pure Scala for a class + companion object, it's not possible with Java's static methods, as these don't belong to any interface.

>

Scala 可以，理论上，创建一个包含某个类的所有静态方法的委托的对象，但它目前不这样做.如果您愿意编写插件，也可以为此编写编译器插件.

Scala could, in theory, create an object containing delegates to all the static methods of some class, but it doesn't do this currently. It's also possible to write a compiler plugin for this if you feel comfortable writing plugins.

否则，您要么必须自己创建一个充满委托的对象，要么只是挑选一些方法并将它们作为函数传递.

Failing that, you'll either have to create an object full of delegates yourself, or just cherry-pick a few methods and pass them around as functions.

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