【发布时间】：2018-05-08 19:56:24
【问题描述】：
我在使用 scalatest 测试我的 akka 流应用程序时遇到 NullPointerException，但不明白为什么......我可能错过了 Akka Streams 中的某些内容，我只是在深入研究它。
我在 scala 2.12.4 和 sbt 1.0.3 中使用 scalatest 的通用代码结构 这是我的应用程序
object CdrToMongoReactiveStream extends App {
implicit val system = ActorSystem("cdr-data-generator")
implicit val materializer = ActorMaterializer()
implicit val executionContext=materializer.executionContext
import RandomCdrJsonProtocol._
val randomCdrThrottledSource : Source[RandomCdr,NotUsed]= Source
.fromIterator(() => Iterator.continually(RandomCdr(msisdnLength,timeRange)))
.throttle(throughput,1.second,1,ThrottleMode.shaping)
.named("randomCdrThrottledSource")
val cdrJsonParseFlow : Flow[RandomCdr,String,NotUsed]= Flow[RandomCdr]
.map((cdr: RandomCdr) => cdr.toJson.toString())
.named("cdrJsonParseFlow")
val mongodbBulkSink : Sink[String,NotUsed] = Flow[String]
.map((json: String) => Document.parse(json))
.map((doc: Document) => new InsertOneModel[Document](doc))
.grouped(bulkSize)
.flatMapConcat { (docs: Seq[InsertOneModel[Document]]) ⇒
Source.fromPublisher(collection.bulkWrite(docs.toList.asJava))
}
.to(Sink.ignore)
val f = randomCdrThrottledSource.via(cdrJsonParseFlow).runWith(mongodbBulkSink)
}
还有我的测试文件
class CdrToMongoReactiveStreamSpec extends WordSpec with Matchers {
import RandomCdrJsonProtocol._
"randomCdrThrottledSource" should {
"generate RandomCdr elements only" in {
val future = CdrToMongoReactiveStream.randomCdrThrottledSource
// line 30 in the error
.runWith(Sink.head)(CdrToMongoReactiveStream.materializer)
val cdr = Await.result(future,10.second)
cdr shouldBe a [RandomCdr]
}
}
"cdrJsonParseFlow" should {
"parse RandomCdr to correct json format" in {
val randomCdr = RandomCdr("+33612345678",1511448336402L,"+33612345678","SMS","OUT",0,0,0)
val (pub,sub) = TestSource.probe[RandomCdr]
.via(CdrToMongoReactiveStream.cdrJsonParseFlow)
.toMat(TestSink.probe[String])(Keep.both)
.run()
sub.request(1)
pub.sendNext(randomCdr)
sub.expectNext() shouldBe equal(randomCdr.toJson.toString())
}
}
}
还有错误提示
java.lang.NullPointerException was thrown.
java.lang.NullPointerException
at CdrToMongoReactiveStreamSpec.$anonfun$new$2(CdrToMongoReactiveStreamSpec.scala:30)
at org.scalatest.OutcomeOf.outcomeOf(OutcomeOf.scala:85)
at org.scalatest.OutcomeOf.outcomeOf$(OutcomeOf.scala:83)
at org.scalatest.OutcomeOf$.outcomeOf(OutcomeOf.scala:104)
at org.scalatest.Transformer.apply(Transformer.scala:22)
at org.scalatest.Transformer.apply(Transformer.scala:20)
at org.scalatest.WordSpecLike$$anon$1.apply(WordSpecLike.scala:1078)
at org.scalatest.TestSuite.withFixture(TestSuite.scala:196)
at org.scalatest.TestSuite.withFixture$(TestSuite.scala:195)
at org.scalatest.WordSpec.withFixture(WordSpec.scala:1881)
at org.scalatest.WordSpecLike.invokeWithFixture$1(WordSpecLike.scala:1076)
at org.scalatest.WordSpecLike.$anonfun$runTest$1(WordSpecLike.scala:1088)
at org.scalatest.SuperEngine.runTestImpl(Engine.scala:289)
at org.scalatest.WordSpecLike.runTest(WordSpecLike.scala:1088)
at org.scalatest.WordSpecLike.runTest$(WordSpecLike.scala:1070)
at org.scalatest.WordSpec.runTest(WordSpec.scala:1881)
at org.scalatest.WordSpecLike.$anonfun$runTests$1(WordSpecLike.scala:1147)
at org.scalatest.SuperEngine.$anonfun$runTestsInBranch$1(Engine.scala:396)
at scala.collection.immutable.List.foreach(List.scala:389)
at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:384)
at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:373)
at org.scalatest.SuperEngine.$anonfun$runTestsInBranch$1(Engine.scala:410)
at scala.collection.immutable.List.foreach(List.scala:389)
at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:384)
at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:379)
at org.scalatest.SuperEngine.runTestsImpl(Engine.scala:461)
at org.scalatest.WordSpecLike.runTests(WordSpecLike.scala:1147)
at org.scalatest.WordSpecLike.runTests$(WordSpecLike.scala:1146)
at org.scalatest.WordSpec.runTests(WordSpec.scala:1881)
at org.scalatest.Suite.run(Suite.scala:1147)
at org.scalatest.Suite.run$(Suite.scala:1129)
at org.scalatest.WordSpec.org$scalatest$WordSpecLike$$super$run(WordSpec.scala:1881)
at org.scalatest.WordSpecLike.$anonfun$run$1(WordSpecLike.scala:1192)
at org.scalatest.SuperEngine.runImpl(Engine.scala:521)
at org.scalatest.WordSpecLike.run(WordSpecLike.scala:1192)
at org.scalatest.WordSpecLike.run$(WordSpecLike.scala:1190)
at org.scalatest.WordSpec.run(WordSpec.scala:1881)
at org.scalatest.tools.SuiteRunner.run(SuiteRunner.scala:45)
at org.scalatest.tools.Runner$.$anonfun$doRunRunRunDaDoRunRun$13(Runner.scala:1340)
at org.scalatest.tools.Runner$.$anonfun$doRunRunRunDaDoRunRun$13$adapted(Runner.scala:1334)
at scala.collection.immutable.List.foreach(List.scala:389)
at org.scalatest.tools.Runner$.doRunRunRunDaDoRunRun(Runner.scala:1334)
at org.scalatest.tools.Runner$.$anonfun$runOptionallyWithPassFailReporter$24(Runner.scala:1031)
at org.scalatest.tools.Runner$.$anonfun$runOptionallyWithPassFailReporter$24$adapted(Runner.scala:1010)
at org.scalatest.tools.Runner$.withClassLoaderAndDispatchReporter(Runner.scala:1500)
at org.scalatest.tools.Runner$.runOptionallyWithPassFailReporter(Runner.scala:1010)
at org.scalatest.tools.Runner$.run(Runner.scala:850)
at org.scalatest.tools.Runner.run(Runner.scala)
at org.jetbrains.plugins.scala.testingSupport.scalaTest.ScalaTestRunner.runScalaTest2(ScalaTestRunner.java:138)
at org.jetbrains.plugins.scala.testingSupport.scalaTest.ScalaTestRunner.main(ScalaTestRunner.java:28)
【问题讨论】：
-
第 30 行的值之一可能为空。您是否尝试过打印它们或使用您的 IDE 调试工具来确定它是哪一个？不清楚哪一行是原始文件中的第 30 行，因为您似乎在运行后删除了一些行。您能否将这些行添加到您的问题中，或者，如果它们不重要，请在没有这些行的情况下再次运行测试，以便我们获得有用的堆栈跟踪？
-
该错误对您的代码没有意义。空指针异常地址
CdrToMongoReactiveStreamSpec.scala:30但您的代码 sn-p 只有 25 行。 -
对不起，我简化了准备就绪的代码。第 30 行是 runwith(...)
标签： scala akka scalatest akka-stream akka-testkit