Question

我试图在intellij中运行一个简单的spark示例，但是我得到了这样的错误：

Exception in thread "main" java.lang.ExceptionInInitializerError
at org.apache.spark.SparkContext.withScope(SparkContext.scala:701)
at org.apache.spark.SparkContext.textFile(SparkContext.scala:819)
at spark.test$.main(test.scala:19)
at spark.test.main(test.scala)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Incompatible Jackson version: 2.7.6
at com.fasterxml.jackson.module.scala.JacksonModule$class.setupModule(JacksonModule.scala:64)
at com.fasterxml.jackson.module.scala.DefaultScalaModule.setupModule(DefaultScalaModule.scala:19)
at com.fasterxml.jackson.databind.ObjectMapper.registerModule(ObjectMapper.java:730)
at org.apache.spark.rdd.RDDOperationScope$.<init>(RDDOperationScope.scala:82)
at org.apache.spark.rdd.RDDOperationScope$.<clinit>(RDDOperationScope.scala)

我试图更新我的杰克逊依赖，但它似乎不起作用，我这样做：

libraryDependencies += "com.fasterxml.jackson.core" % "jackson-core" % "2.8.7"
libraryDependencies += "com.fasterxml.jackson.core" % "jackson-databind" % "2.8.7"

但它仍然显示相同的错误消息，有人可以帮我修复错误吗？

这是spark示例代码：

object test {
def main(args: Array[String]): Unit = {
    if (args.length < 1) {
        System.err.println("Usage: <file>")
        System.exit(1)
    }

    val conf = new SparkConf()
    val sc = new SparkContext("local","wordcount",conf)
    val line = sc.textFile(args(0))

    line.flatMap(_.split(" ")).map((_, 1)).reduceByKey(_+_).collect().foreach(println)

    sc.stop()
    }
}

这是我的built.sbt：

name := "testSpark2"

version := "1.0"

scalaVersion := "2.11.8"


libraryDependencies += "com.fasterxml.jackson.core" % "jackson-core" % "2.8.7"
libraryDependencies += "com.fasterxml.jackson.core" % "jackson-databind" % "2.8.7"

libraryDependencies += "org.apache.spark" % "spark-core_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-mllib_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-repl_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-streaming-flume_2.10" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-sql_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-network-shuffle_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-streaming-kafka-0-10_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-hive_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-streaming-flume-assembly_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-mesos_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-graphx_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-catalyst_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-launcher_2.11" % "2.1.0"

Answer 1

Spark 2.1.0包含com.fasterxml.jackson.core作为传递依赖。因此，我们不需要在libraryDependencies中包含。

但是如果你想添加一个不同的com.fasterxml.jackson.core依赖项版本，那么你必须覆盖它们。像这样：

name := "testSpark2"

version := "1.0"

scalaVersion := "2.11.8"


dependencyOverrides += "com.fasterxml.jackson.core" % "jackson-core" % "2.8.7"
dependencyOverrides += "com.fasterxml.jackson.core" % "jackson-databind" % "2.8.7"
dependencyOverrides += "com.fasterxml.jackson.module" % "jackson-module-scala_2.11" % "2.8.7"

libraryDependencies += "org.apache.spark" % "spark-core_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-mllib_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-repl_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-streaming-flume_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-sql_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-network-shuffle_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-streaming-kafka-0-10_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-hive_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-streaming-flume-assembly_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-mesos_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-graphx_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-catalyst_2.11" % "2.1.0"
libraryDependencies += "org.apache.spark" % "spark-launcher_2.11" % "2.1.0"

所以，像上面的那样更改你的build.sbt，它会按预期工作。

我希望它有所帮助！

Answer 2

FYI。对于我的情况，我在应用程序中使用spark和kafka-streams，而kafka-streams使用com.fasterxml.jackson.core 2.8.5。添加exclude如下修复了问题

（gradle这个）

compile (group: "org.apache.kafka", name: "kafka-streams", version: "0.11.0.0"){
    exclude group:"com.fasterxml.jackson.core"
}

Answer 3

通过使用resolutionStrategy（https://docs.gradle.org/current/dsl/org.gradle.api.artifacts.ResolutionStrategy.html）实现Gradle解决方案：

configurations {

    all {

        resolutionStrategy {
            force 'com.fasterxml.jackson.core:jackson-core:2.4.4', 'com.fasterxml.jackson.core:jackson-databind:2.4.4', 'com.fasterxml.jackson.core:jackson-annotations:2.4.4'
        }
    }
}

Spark2.1.0与Jackson版本2.7.6不兼容

3 个答案: