chapter09

  import java.io.File
  import java.nio.file._

  import scala.collection.mutable.ArrayBuffer
/**
  * Created by EX-CHENZECHAO001 on 2018-04-02.
  */
class Chapter09 {
  // 9.7 访问目录
  def subdirs(dir: File): Iterator[File] = {
    val children = dir.listFiles().filter(_.isDirectory)
    children.toIterator ++ children.toIterator.flatMap(subdirs(_))
  }
  implicit def makeFileVisitor(f: (Path) => Unit) = new SimpleFileVisitor[Path] {

  }
}




object Chapter09 extends App{
  val files = new Chapter09().subdirs(new File("D:\chenzechao\_learn"))
  for(file <- files){
    println(file.getName)
  }
}

  // 9.8 序列化
  class Person98 extends Serializable {

  }
  // 如果接受缺省ID，可略去@SerialVersionUID
  // 按常规方式对对象进行序列化和反序列化
  object Person98 {
    val fred = new Person98()
    import java.io._
    val out = new ObjectOutputStream(new FileOutputStream("/tmp/abc.obj"))
    out.writeObject(fred)
    out.close()
    val in =  new ObjectInputStream(new FileInputStream("/tmp/abc.obj"))
    val saveFred = in.readObject().asInstanceOf[Person98]

    // Scala集合类都是可序列化的
    class Person98_01 extends Serializable{
      private val friends = new ArrayBuffer[Person98]
    }
  }

  // 9.8 进程控制
  import sys.process._
//  "ls -al .."
  // sys.process包包含一个从字符器到ProcessBuilder对象的隐式转换。!操作符执行的就是这个ProcessBuilder对象
  // !操作符返回的被执行程序的返回值：程序成功执行的话就是0，否则就是显示错误的非0值
  // 如果使用!!则返回命令执行结果
  val result = "ls -al .." !!