解决 Scala 中模糊的隐式转换

问题描述

有什么方法可以在下面选择使用 asJavaIterable 吗?我知道我可以拼出那个特定的函数名称，但我想知道我是否可以声明性地指定我想要的类型.我也很好奇为什么 asJavaIterable 没有优先于 asJavaCollection.

Any way to opt to use asJavaIterable in the following? I know I can just spell out that particular function name, but I'm wondering if I can just declaritively specify the type I want. I'm also curious why asJavaIterable isn't taking precedence over asJavaCollection.

scala> import scala.collection.JavaConversions._
import scala.collection.JavaConversions._

scala> Iterable(0,1):java.lang.Iterable[Int]
<console>:11: error: type mismatch;
 found   : Iterable[Int]
 required: java.lang.Iterable[Int]
Note that implicit conversions are not applicable because they are ambiguous:
 both method asJavaIterable in object JavaConversions of type [A](i: Iterable[A])java.lang.Iterable[A]
 and method asJavaCollection in object JavaConversions of type [A](i: Iterable[A])java.util.Collection[A]
 are possible conversion functions from Iterable[Int] to java.lang.Iterable[Int]
       Iterable(0,1):java.lang.Iterable[Int]
               ^

推荐答案

可以限制导入的范围，以便不考虑 asJavaCollection:

It's possible to limit the scope of the import so that asJavaCollection will not be considered:

import scala.collection.JavaConversions.{asJavaCollection=>_,_}

这表示导入 JavaConversions 的所有成员，除了 asJavaCollection".

This says, "import all members of JavaConversions, except asJavaCollection".

但是，我认为最好导入 JavaConverters 并使您的转换显式.

However, I think its preferable to import JavaConverters and make your conversions explicit.

import scala.collection.JavaConverters._

Iterable(0,1).asJava

这篇关于解决 Scala 中模糊的隐式转换的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！