将Scala反射与Java反射一起使用 [英] Using Scala reflection with Java reflection
问题描述
作为DSL的一部分，我有很多代码一直在使用Java反射来调用Java对象上用户指定的任意方法.
I have a lot of code that has been using Java reflection to invoke arbitrary user-specified methods on Java objects, as part of a DSL.
但是，实际上，其中的许多Java对象都是Scala对象，并且其中的某些方法都使用Scala @deprecated批注进行标记.不幸的是，Java的注释机制无法看到Scala注释，并且直到Scala 2.10为止(我知道吗?)没有方便的方法来访问这些注释.
However, a lot of those Java objects, in practice, are Scala objects, and some of the methods on them are marked with the Scala @deprecated annotation. Unfortunately, Java's annotations mechanism cannot see Scala annotations, and until Scala 2.10 there was no convenient way (that I know of?) to get access to those annotations.
我终于升级到2.10，并且希望能够从DSL发出弃用警告.但是，我不想重写整个求值器(至少现在是这样)以使用Scala反射，因此有一种简便的方法可以将java.lang.reflect.Method转换为可以使用Scala反射的值，以确定是否不建议使用Scala方法?还是我必须先使用Scala反射来复制很多现有的方法解析逻辑，然后才能获得该信息?
I have finally upgraded to 2.10, and would like to be able to emit deprecation warnings from my DSL. However, I don't want to rewrite the entire evaluator (for now, at least) to use Scala reflection, so is there a convenient way to go from a java.lang.reflect.Method to something I can use Scala reflection on to figure out if the Scala method in question is deprecated? Or will I have to duplicate a lot of the existing method resolution logic using Scala reflection before I can get at that information?
它看起来像曾经存在于Scala反射中的JavaToScala类，其中有一个methodToScala方法可以满足我的要求.我能找到的唯一跟踪记录是
It looks like a JavaToScala class used to exist in Scala reflection, which had a methodToScala method in it that did what I want. The only trace I can find is here, in a google code project. Why was the functionality moved out of core reflection? Or is it still there under a different name?
看起来该代码存在于scala.reflect.runtime.JavaMirrors中，但是不幸的是它是私有的(还有另一个JavaMirrors是公共API的一部分，但没有提供我需要的任何内容.)我如果存在通过公共API进行调用的路径"，将我带到深埋在私有JavaMirrors中的私有methodAsScala，则无法确定我的生活.至少可以说，这令人沮丧:(
It looks like the code in question lives on in scala.reflect.runtime.JavaMirrors, but unfortunately it's private (there's another JavaMirrors that is part of the public API, but doesn't provide any of what I need.) I can't figure out for the life of me if there's a "path" of invocations through a public API that takes me all the way down to the private methodAsScala buried deep within the private JavaMirrors. It's frustrating, to say the least :(
推荐答案
这是一个快速解决方法(贷记@EugeneBurmako)
Here is a quick fix (credits to @EugeneBurmako)
https://gist.github.com/xeno-by/5277805
对此已提出问题(贷方为@MysteriousDan):
An issue has been filed for this (credits to @MysteriousDan):
https://issues.scala-lang.org/browse/SI-7317
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