java - Apache Spark : ERROR local class incompatible when initiating a SparkContext class

Question

您好，我在 Spark 网站上运行示例 http://spark.apache.org/docs/1.2.0/quick-start.html#self-contained-applications

spark版本:spark-1.4.0

sbt 版本:0.13.8

我运行命令“sbt run”并得到错误“java.io.InvalidClassException:org.apache.spark.deploy.ApplicationDescription；本地类不兼容”。

当我尝试启动 SparkContext 类时，此应用程序在“val sc = new SparkContext(conf)”处失败。我用谷歌搜索并看到 this post但我没有使用 hadoop-client。

可以请你检查一下吗？我的猜测是 build.sbt 中的版本问题。非常感谢。

更新:我已尝试提交 python 应用程序并且工作正常，这意味着 Spark 集群正常。

scala代码如下:

/* SimpleApp.scala */
import org.apache.spark.SparkContext
import org.apache.spark.SparkContext._
import org.apache.spark.SparkConf

object SimpleApp {
  def main(args: Array[String]) {
    val logFile = "YOUR_SPARK_HOME/README.md" // Should be some file on your system
    val conf = new SparkConf().setAppName("Simple Application")
    val sc = new SparkContext(conf)
    val logData = sc.textFile(logFile, 2).cache()
    val numAs = logData.filter(line => line.contains("a")).count()
    val numBs = logData.filter(line => line.contains("b")).count()
    println("Lines with a: %s, Lines with b: %s".format(numAs, numBs))
  }
}

built.sbt 如下:

name := "Simple Project"

version := "1.0"

scalaVersion := "2.10.4"

libraryDependencies += "org.apache.spark" %% "spark-core" % "1.2.0"

错误信息如下:

15/08/27 05:23:38 ERROR Remoting: org.apache.spark.deploy.ApplicationDescription; local class incompatible: stream classdesc serialVersionUID = 7674242335164700840, local class serialVersionUID = -7685200927816255400
java.io.InvalidClassException: org.apache.spark.deploy.ApplicationDescription; local class incompatible: stream classdesc serialVersionUID = 7674242335164700840, local class serialVersionUID = -7685200927816255400
    at java.io.ObjectStreamClass.initNonProxy(ObjectStreamClass.java:617)
    at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1622)
    at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1517)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1771)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
    at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1990)
    at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1915)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1798)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1350)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:370)
    at akka.serialization.JavaSerializer$$anonfun$1.apply(Serializer.scala:136)
    at scala.util.DynamicVariable.withValue(DynamicVariable.scala:57)
    at akka.serialization.JavaSerializer.fromBinary(Serializer.scala:136)
    at akka.serialization.Serialization$$anonfun$deserialize$1.apply(Serialization.scala:104)
    at scala.util.Try$.apply(Try.scala:161)
    at akka.serialization.Serialization.deserialize(Serialization.scala:98)
    at akka.remote.serialization.MessageContainerSerializer.fromBinary(MessageContainerSerializer.scala:63)
    at akka.serialization.Serialization$$anonfun$deserialize$1.apply(Serialization.scala:104)
    at scala.util.Try$.apply(Try.scala:161)
    at akka.serialization.Serialization.deserialize(Serialization.scala:98)
    at akka.remote.MessageSerializer$.deserialize(MessageSerializer.scala:23)
    at akka.remote.DefaultMessageDispatcher.payload$lzycompute$1(Endpoint.scala:58)
    at akka.remote.DefaultMessageDispatcher.payload$1(Endpoint.scala:58)
    at akka.remote.DefaultMessageDispatcher.dispatch(Endpoint.scala:76)
    at akka.remote.EndpointReader$$anonfun$receive$2.applyOrElse(Endpoint.scala:937)
    at akka.actor.Actor$class.aroundReceive(Actor.scala:465)
    at akka.remote.EndpointActor.aroundReceive(Endpoint.scala:415)
    at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516)
    at akka.actor.ActorCell.invoke(ActorCell.scala:487)
    at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:238)
    at akka.dispatch.Mailbox.run(Mailbox.scala:220)
    at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:393)
    at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
    at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
    at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
    at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)

Answer 1

您说您正在使用 Spark 1.4.0 集群运行，但您的 build.sbt 正在使用 1.2.0 构建。请在您的 build.sbt 中更改为:

libraryDependencies += "org.apache.spark" %% "spark-core" % "1.4.0"