flink的版本：1.4.0、1.4.1、1.4.2
当我尝试制作这个简单的flink应用程序时

val env: StreamExecutionEnvironment = 
  StreamExecutionEnvironment.getExecutionEnvironment
env.fromElements("a", "b", "c").addSink(new BucketingSink[String]("file:///Users/joshlemer/projects/my-project/target/output"))

我得到以下运行时异常：

Exception in thread "main" java.lang.NoClassDefFoundError: Lorg/apache/hadoop/fs/FileSystem;
    at java.lang.Class.getDeclaredFields0(Native Method)
    at java.lang.Class.privateGetDeclaredFields(Class.java:2583)
    at java.lang.Class.getDeclaredFields(Class.java:1916)
    at org.apache.flink.api.java.ClosureCleaner.clean(ClosureCleaner.java:72)
    at org.apache.flink.streaming.api.environment.StreamExecutionEnvironment.clean(StreamExecutionEnvironment.java:1550)
    at org.apache.flink.streaming.api.datastream.DataStream.clean(DataStream.java:184)
    at org.apache.flink.streaming.api.datastream.DataStream.addSink(DataStream.java:1134)
    at org.apache.flink.streaming.api.scala.DataStream.addSink(DataStream.scala:1036)
    at com.company.project.Job$.run(Job.scala:52)
    at com.company.project.Job$.main(Job.scala:28)
    at com.company.project.Job.main(Job.scala)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FileSystem
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

即使我可以用 dataStream.writeAsText(...) .
我的build.sbt也很典型：

val flinkVersion = "1.4.2"
val flinkDependencies =
  Seq(
    "org.apache.flink" %% "flink-scala" % flinkVersion % "provided",
    "org.apache.flink" %% "flink-streaming-scala" % flinkVersion % "provided",
    "org.apache.flink" %% "flink-statebackend-rocksdb" % flinkVersion,
    "org.apache.flink" %% "flink-connector-kafka-0.11" % flinkVersion,
    "org.apache.flink" %% "flink-connector-filesystem" % flinkVersion,
    "org.apache.flink" %% "flink-test-utils" % flinkVersion % "test",
    "org.apache.flink" % "flink-test-utils-junit" % flinkVersion % "test"
  )

额外的 idea.sbt 正如flink为intellij用户推荐的那样

lazy val mainRunner = project.in(file("mainRunner")).dependsOn(RootProject(file("."))).settings(
  // we set all provided dependencies to none, so that they are included in the classpath of mainRunner
  libraryDependencies := (libraryDependencies in RootProject(file("."))).value.map{
    module =>
      if (module.configurations.equals(Some("provided"))) {
        module.copy(configurations = None)
      } else {
        module
      }
  }
)

我用它来运行应用程序（mainrunner被设置为应用程序类路径）。
我很困惑为什么会发生这种情况，尤其是为什么程序包以“lorg”而不是“org”开头？
谢谢！