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 }