scala 读取txt文件的方法示例

文件格式分别如下

package txt

object ReadTxt {

 def readFromTxtByLine(filePath:String) = {
 //导入Scala的IO包
 import scala.io.Source
 //以指定的UTF-8字符集读取文件，第一个参数可以是字符串或者是java.io.File
 val source = Source.fromFile(filePath, "UTF-8")
 //或取文件中所有行
 //val lineIterator = source.getLines()
 //迭代打印所有行
 //lineIterator.foreach()
 //将所有行放到数组中
 val lines = source.getLines().toArray
 source.close()
 //println(lines.size)
 lines
 }

 def LackingFileUtil(array:Array[String],keyMap:Map[String,String]) = {
 // 使用for循环和until遍历Array / ArrayBuffer
 // 使until是RichInt提供的函数
 var lockMapList = List[Map[String,String]]()
 for (i <- 0 until array.length){
  if(i==0){
  val lineArray = array(i).trim.split("\\|")
  lockMapList = lockMapList :+ Map("id"->lineArray(0).trim,"name"->lineArray(1).trim,"pass"->lineArray(2).trim)
  }else{
  val lineArray = array(i).split(",")
  if(lineArray.length==3){
   lockMapList = lockMapList :+ Map("id"->lineArray(0).trim,"name"->lineArray(1).trim,"pass"->lineArray(2).trim)
  }else if(lineArray.length==2){
   val pass = keyMap.getOrElse(lineArray(0).trim,lineArray(1).trim)
   lockMapList = lockMapList :+ Map("id"->lineArray(0).trim,"name"->lineArray(1).trim,"pass"->pass.trim)
  }else if(lineArray.length==1){
   lockMapList = lockMapList :+ Map("id"->lineArray(0).trim,"name"->"","pass"->"")
  }else{
   lockMapList = lockMapList :+ Map("id"->"-","name"->"","pass"->"")
  }
  }
  //println(array(i))
 }
 lockMapList

 // 跳跃遍历Array / ArrayBuffer
 /*for(i <- 0 until (array.length, 2))
  println(array(i))*/

 // 从尾部遍历Array / ArrayBuffer
 /*for(i <- (0 until array.length).reverse)
  println(array(i))*/

 // 使用“增强for循环”遍历Array / ArrayBuffer
 /*for (e <- array){
  println(e)
  e.split(",").mkString
 }*/

 }

 def KeyFileUtil(array:Array[String]) = {
 var keyMapList = Map[String, String]()
 for (i <- 0 until array.length) {
  //println(array(i))
  val lineArray = array(i).trim.split(",")
  //println(lineArray.size)
  if(lineArray.size==2){
  keyMapList = keyMapList ++ Map(lineArray(0).trim -> lineArray(1).trim)
  }else if(lineArray.size==1){
  keyMapList = keyMapList ++ Map(lineArray(0).trim -> "")
  }else{
  keyMapList = keyMapList ++ Map("-" -> "")
  }
 }
 keyMapList
 }

 def isEmpty(s: String): Boolean = (s == null) || (s.size==0)
}

package txt

import scala.reflect.io.File

object App {

 def main(args: Array[String]): Unit = {

 val key = ReadTxt.readFromTxtByLine("D:"+File.separator+"workspace"+File.separator+"source.txt")
 //println(key.mkString)
 val keyMap = ReadTxt.KeyFileUtil(key)

 //println(keyMap)

 val lack = ReadTxt.readFromTxtByLine("D:"+File.separator+"workspace"+File.separator+"source1.txt")

 val lockMapList = ReadTxt.LackingFileUtil(lack,keyMap)

 println(lockMapList)

 }
}

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