Scala统计一个文件所有单词出现的次数

 1 import scala.io.Source
 2
 3 object WordCount extends App {
 4
 5   val path = "C:\\Users\\Administrator\\Desktop\\ff\\fzsExample\\src"
 6   val file = new File(path)
 7   val files = file.listFiles().filter(_.isFile)
 8   val mapData = scala.collection.mutable.Map[String, Int]()
 9
10   def readFile(item : File): Unit = {
11     try {
12         Source.fromFile(item).getLines().flatMap(_.split("\\s+")).toList.map(x => {
13         mapData.get(x) match {
14           case Some(b) => mapData += ( x -> b.+(1))
15           case None => mapData += ( x -> 1)
16         }
17       })
18     }catch{
19       case e1: FileNotFoundException => println("FileNotFoundException")
20       case e2: RuntimeException => println("RuntimeException")
21       case e3: Exception => println("Exception")
22     }
23   }
24
25   files.map(readFile)
26   println(mapData)  

方法二：

1  val wordlist = Source.fromFile(item).getLines().flatMap(line => line.split(" ")).map(word => (word, 1))
2    //方法一：先groupBy再map
3    wordlist.groupBy(_._1).map {
4      case (word, list) => (word, list.size)
5    }.foreach(println)
6
7 }