访问斯卡拉期货返回的价值 [英] Accessing value returned by scala futures

问题描述

我是scala期货的新手，并且对scala期货的回报价值有疑问.

I am a newbie to scala futures and I have a doubt regarding the return value of scala futures.

因此，一般来说，scala未来的语法是

So, generally syntax for a scala future is

 def downloadPage(url: URL) = Future[List[Int]] {

 }

我想知道如何从其他调用此方法的方法访问List[Int].

I want to know how to access the List[Int] from some other method which calls this method.

换句话说，

val result = downloadPage("localhost") 

那么，将List[Int]淘汰的方法应该是什么?

then what should be the approach to get List[Int] out of the future ?

我尝试使用map方法，但无法成功完成此操作.

I have tried using map method but not able to do this successfully.`

推荐答案

成功案例(listInt)=>我想返回listInt，但我不知道该怎么做.

The case of Success(listInt) => I want to return the listInt and I am not able to figure out how to do that.

最佳做法是您不返回该值.相反，您只是将未来(或用map，flatMap等转换的版本)传递给需要此值的每个人，他们可以添加自己的onComplete.

The best practice is that you don't return the value. Instead you just pass the future (or a version transformed with map, flatMap, etc.) to everyone who needs this value and they can add their own onComplete.

如果您确实需要返回它(例如，在实现传统方法时)，那么您唯一可以做的就是阻止(例如，使用

If you really need to return it (e.g. when implementing a legacy method), then the only thing you can do is to block (e.g. with Await.result) and you need to decide how long to await.

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