java - 如何将 Java 双冒号运算符 (::) 翻译成 Scala？

Question

我想使用 camunda-bpm-assert-scenario在我的 ScalaTests 中。

我有这段代码 receiveTask::receive:

when(documentRequest.waitsAtReceiveTask("ReceiveTaskWaitForDocuments")).thenReturn((receiveTask) -> {
  receiveTask.defer("P1DT1M", receiveTask::receive);
});

根据Is it possible to use a Java 8 style method references in Scala?中的回答我可以很容易地将其翻译成:

receiveTask.defer("P1D", receiveTask.receive _)

但这给了我:

Error:(84, 45) type mismatch;
 found   : Unit
 required: org.camunda.bpm.scenario.defer.Deferred
       receiveTask.defer("P1D", receiveTask.receive _)

这是接收函数:

void receive();

这是预期的界面:

public interface Deferred {
  void execute() throws Exception;
}

我如何在 Scala 中实现这一点？ 这不是 Is it possible to use a Java 8 style method references in Scala? 的副本，没有解决“Error:(84, 45) type mismatch; ……”

Answer 1

看完这篇stackoverflow answer ，我可以解决它:

receiveTask.defer("P1D", new Deferred{
         def execute(): Unit = receiveTask.receive()
       })

Intellij 建议将其转换为单一抽象方法:

receiveTask.defer("P1D", () => receiveTask.receive())

问题是 receive 还有一个带参数的重载函数。