scala - 定义 Play for Scala 中的 future 隐式上下文

Question

除了 Scala 提供的 future 执行上下文之外:

import scala.concurrent.ExecutionContext.Implicits.global

Play 提供了另一个执行上下文:

import play.api.libs.concurrent.Execution.Implicits.defaultContext

何时在 Play for Scala 中使用每个选项？

Answer 1

您可以在这里找到答案:

Play's internal execution context

这个问题并不完全重复，但非常接近，那里的答案也涵盖了您的问题。

简而言之:

您不得在 Play 中使用import scala.concurrent.ExecutionContext.Implicits.global。

回复评论

引用答案:

Instead, you would use play.api.libs.concurrent.Execution.Implicits.defaultContext, which uses an ActorSystem.

scala.concurrent.ExecutionContext.Implicits.global is an ExecutionContext defined in the Scala standard library. It is a special ForkJoinPool that using the blocking method to handle potentially blocking code in order to spawn new threads in the pool. You really shouldn't use this in a Play application, as Play will have no control over it. It also has the potential to spawn a lot of threads and use a ton of memory, if you're not careful.