Question

所以我一直在尝试使用signal-collect框架，我下载了.jar个文件并将其解压缩到一个文件夹中。目前文件夹结构如下：

LICENSE.txt  
PageRank.scala  
core-1.1.1-sources.jar  
dependencies/  
javaapi-1.1.1-sources.jar  
NOTICE.txt  
README.txt  
core-1.1.1.jar  
javaapi-1.1.1-javadoc.jar  
javaapi-1.1.1.jar

PageRank.scala是他们提供的Scala测试代码，其中包括：

import com.signalcollect._

object PageRank extends App {
  val graph = GraphBuilder.build
  graph.addVertex(new PageRankVertex(id=1))
  graph.addVertex(new PageRankVertex(id=2))
  graph.addEdge(new PageRankEdge(sourceId=1, targetId=2))
  graph.addEdge(new PageRankEdge(sourceId=2, targetId=1))
  graph.execute
  graph.foreachVertex(println(_))
  graph.shutdown
}

class PageRankVertex(id: Any, dampingFactor: Double=0.85)
    extends DataGraphVertex(id=id, state=1-dampingFactor) {
  type Signal = Double

  def collect(oldState: Double, mostRecentSignals: Iterable[Double]): Double = {
    1 - dampingFactor + dampingFactor * mostRecentSignals.sum
  }

}

class PageRankEdge(sourceId: Any, targetId: Any)
    extends DefaultEdge(sourceId, targetId) {
  type SourceVertex = PageRankVertex

  def signal(sourceVertex: PageRankVertex) = {
    sourceVertex.state * weight / sourceVertex.sumOfOutWeights
  }

}

对于JVM / Java / Scala，我是新手，这是我尝试将.jar's添加到类路径以编译PageRank.scala：

$ scalac -classpath *.jar dependencies/*.jar PageRank.scala 
error: IO error while decoding core-1.1.1.jar with UTF-8
Please try specifying another one using the -encoding option
error: IO error while decoding javaapi-1.1.1-javadoc.jar with UTF-8
Please try specifying another one using the -encoding option
error: IO error while decoding javaapi-1.1.1-sources.jar with UTF-8
Please try specifying another one using the -encoding option
error: IO error while decoding javaapi-1.1.1.jar with UTF-8
Please try specifying another one using the -encoding option
error: IO error while decoding dependencies/je-3.2.76.jar with UTF-8
Please try specifying another one using the -encoding option
error: IO error while decoding dependencies/scala-library-2.9.1.jar with UTF-8
Please try specifying another one using the -encoding option
6 errors found

我无法弄清楚出了什么问题......发生了什么事？谢谢！问候， -kstruct

Answer 1

您需要将两个类路径路径作为单个参数传递。

试试这个：

$ scalac -classpath "*.jar:dependencies/*.jar" PageRank.scala
$ scala -classpath "*.jar:dependencies/*.jar" PageRank
PageRankVertex(id=2, state=0.9999999999999997)
PageRankVertex(id=1, state=0.9999999999999997)

它对我有用。

Answer 2

似乎根据已安装的Java版本，类路径中包含多个JAR的通配符可能会也可能不起作用。我在StackOverflow的其他地方找到了https://neo4j.com/docs/java-reference/current/#tutorial-traversal（请注意，你可以在'echo'后面有多个文件夹，用空格分隔）：

scalac -classpath $(echo *.jar dependencies/*.jar | tr ' ' ':')  PageRank.scala
scala -classpath $(echo *.jar dependencies/*.jar | tr ' ' ':')  PageRank

Answer 3

为简单起见，您可以使用： scala -classpath $（echo * .jar依赖项/*.jar | tr'''：'）PageRank.scala

将.jar添加到classpath（Scala）

3 个答案: