将Scala future转换为CompletableFuture错误

Question

我正在使用这个库（https://github.com/scala/scala-java8-compat）将Scala Future转换为Java 8 CompletableFuture。

但是运行这个例子：

package utils;

import akka.dispatch.Futures;
import org.junit.Test;
import scala.concurrent.Future;

import java.util.concurrent.CompletableFuture;

import scala.compat.java8.FutureConverters;
import scala.concurrent.Promise;

public class ScalaFuture {
@Test
public void test() throws InterruptedException {
    Promise promise = Futures.promise();
    Future scalaFuture = promise.future();
    CompletableFuture cf = FutureConverters.toJava(scalaFuture).toCompletableFuture();
    cf.whenComplete((result, t) -> {
        System.out.println(result);
    });
    promise.success("works");
    Thread.sleep(1000);
}

我有这个错误

java.lang.NoClassDefFoundError: scala/Function1$class

    at scala.concurrent.java8.FuturesConvertersImpl$CF.<init>(FutureConvertersImpl.scala:18)
    at scala.compat.java8.FutureConverters$.toJava(FutureConverters.scala:60)
    at scala.compat.java8.FutureConverters.toJava(FutureConverters.scala)
    at utils.ScalaFuture.test(ScalaFuture.java:19)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:564)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.ClassNotFoundException: scala.Function1$class
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:185)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:496)
    ... 26 more

知道我的代码有什么问题吗？