Scala文件操作----(读取和写入字符)

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如果有以下情景，怎么用scala实现读写文件？

1、实现读取以下文件内容

E:/device_level

2、将字符串写入文件

"E:/test.txt"

实现如下：

package com.ngaa.scala.testimport java.io.{ByteArrayInputStream, File, FileInputStream, InputStream}import scala.io.BufferedSource/**  * Created by jfei_yang on 20170705.  * Update date:  * Time: 10:50  * Project: sparkmvn  * Package: com.ngaa.scala.test  * Describle : 测试scala读写文件操作  *  * Result of Test: 测试通过  * Command:  *  *  * Email:  jifei.yang@ngaa.com.cn  * Status：线上正在使用  * Machine ip:  * ^^集群----->192.168.1.1（001业务统计）  * ^^集群----->127.0.0.1  （002业务统计）  *  * Attention：  *  *  */object TestNgaaUtils {  def main(args: Array[String]) {    val str="http://stat-y.xywy.com/vclick.png?Type=visit&Url=http%3A%2F%2Fm.so.xywy.com%2Fcomse.php%3Fsrc%3D3gclubso%26keyword%3D%25E5%259B%259B%25E5%258D%2581%25E5%2587%25A0%25E5%25B2%2581%25E7%2594%25B7%25E4%25BA%25BA%25E5%25BF%2583%2\n5E7%2590%2586&Domain=m.so.xywy.com&ClientId=1499086455712135328943326&ClientVisitNumber=7&ClientVisitNumberDay=7&SessionId=149908645571212102385&SessionNumber=7&LoginId=&UserType=&UrlKeyWord=%E5%9B%9B%E5%8D%81%E5%87%A0%E5%B2%81%E7%94%B7%E4%BA%BA%E5%BF%83%E7%90%86&TypeId\n=zhao&XPoint=15&YPoint=172&Height=80&Width=330&ItemId=m_detail_circles&Href=&TagName=DIV&Text=&Params=t%3Dmagicube%26n%3Dm_detail_circles%26p%3D1%26w%3D%E5%85%B6%E4%BB%96%E7%96%BE%E7%97%85%E5%9C%88&RandomNum=0.23594240844249725&RefKeyWord=&Redomain=3g.club.xywy.com&Ref=\nhttp%3A%2F%2F3g.club.xywy.com%2Fstatic%2F20140610%2F45407765.htm"    //从文件中读取字符串    val json=inputToString(new FileInputStream ("E:/device_level"))    //将字符串写入文件    inputToFile(str2InputStream(str),new File("E:/test.txt"))    println(json)      }  //可以从InputStream中读取文件字符串  def inputToString(is: java.io.InputStream): String = {    val lines: Iterator[String] = scala.io.Source.fromInputStream(is, "utf-8").getLines()    val sb = new StringBuilder()    lines.foreach(sb.append(_))    sb.toString()  }  //将输入流写入文件(test.txt)中  //参数f---> val file = new File("F:/test.txt")  def inputToFile(is: java.io.InputStream, f: java.io.File) {    val in: BufferedSource = scala.io.Source.fromInputStream(is)    val out = new java.io.PrintWriter(f)    try {      in.getLines().foreach(out.print(_))//等价write，只是多了一句if(s==null)s="null"    }    finally {      out.close    }  }  /**    * string to inputStream    * @param str    * @return    */  def str2InputStream(str:String):InputStream={    new  ByteArrayInputStream(str.getBytes())  }}

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