scala - java.lang.NoClassDefFoundError:scala/Product $ class

Question

我是scala的新手，正在尝试一些示例代码进行测试。但是，当我运行测试代码时，我遇到了一些问题。运行测试时，出现错误

[trace] Stack trace suppressed: run last test:executeTests for the full output.
[error] (test:executeTests) java.lang.NoClassDefFoundError: scala/Product$class
[error] Total time: 3 s, completed Feb 27, 2017 6:57:15 PM

我的代码如下

FilterChecks.scala

    class filterChecks extends FlatSpec {

  "Filter checker passed a filename which is present in directory" should "return file name" in {
    val matchingFileName = new FileObject("match")
    val listOfFiles = List(new FileObject("random"), matchingFileName)
    val matchedFiles = new FilterChecker("match").findMatchedFiles(listOfFiles)
    assert(matchedFiles == List(matchingFileName))

  }
}

FilterChecker类别

class FilterChecker(filter : String) {

  def matches(content : String) = content.contains(filter);

  def findMatchedFiles(fileObjects : List[FileObject]) = {
    for(fileObject <- fileObjects if(matches(fileObject.name)))
      yield fileObject
  }

}

文件对象

class FileObject(val name: String) {

}

生成文件如下:

name := "testScalaProject"

version := "1.0"

scalaVersion := "2.12.1"

// https://mvnrepository.com/artifact/org.scala-js/scalajs-test-interface_2.12
libraryDependencies ++= Seq("org.scala-js" % "scalajs-test-interface_2.12" % "0.6.14",
  "org.scalatest" % "scalatest_2.11" % "2.2.5",
  "com.novocode" % "junit-interface" % "0.11",
  "org.scala-lang" % "scala-library" % "2.12.1")

有人可以帮我解决问题。提前致谢

Answer 1

您的sbt构建文件不正确。您的scala版本是2.12.x，但是您使用的是在scala 2.11版本中编译的库。使用如下所示的sbt设置

注意:我更改了scalatest的版本，因为2.12版本的scala不再支持2.x版本

scalaVersion := "2.12.1"

libraryDependencies ++= Seq(
  "org.scala-js" %% "scalajs-test-interface" % "0.6.14",
  "org.scalatest" %% "scalatest" % "3.0.1", //version changed as these the only versions supported by 2.12
  "com.novocode" % "junit-interface" % "0.11",
  "org.scala-lang" % "scala-library" % scalaVersion.value
)

记得在sbt控制台中执行 reload， clean和 compile来开始干净的编译