Scala example source code file (Directory.scala)

This example Scala source code file (Directory.scala) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Scala tags/keywords

directory, directory, file, file, int, iterator, iterator, jfile, none, none, option, path, string, tmpdir

The Scala Directory.scala source code

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2003-2011, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */

package scala.tools.nsc
package io

object Directory {
  import scala.util.Properties.{ tmpDir, userHome, userDir }
  
  private def normalizePath(s: String) = Some(apply(Path(s).normalize))
  def Current: Option[Directory]  = if (userDir == "") None else normalizePath(userDir)
  def Home: Option[Directory]     = if (userHome == "") None else normalizePath(userHome)
  def TmpDir: Option[Directory]   = if (tmpDir == "") None else normalizePath(tmpDir)
    
  def apply(path: Path): Directory = path.toDirectory
  
  // Like File.makeTemp but creates a directory instead
  def makeTemp(prefix: String = Path.randomPrefix, suffix: String = null, dir: JFile = null): Directory = {
    val path = File.makeTemp(prefix, suffix, dir)
    path.delete()
    path.createDirectory()
  }
}
import Path._

/** An abstraction for directories.
 *
 *  @author  Paul Phillips
 *  @since   2.8
 */
class Directory(jfile: JFile) extends Path(jfile) {  
  override def toAbsolute: Directory = if (isAbsolute) this else super.toAbsolute.toDirectory
  override def toDirectory: Directory = this
  override def toFile: File = new File(jfile)
  override def isValid = jfile.isDirectory() || !jfile.exists()
  override def normalize: Directory = super.normalize.toDirectory  
  
  /** An iterator over the contents of this directory.
   */
  def list: Iterator[Path] =
    jfile.listFiles match {
      case null   => Iterator.empty
      case xs     => xs.iterator map Path.apply
    }
  
  def dirs: Iterator[Directory] = list collect { case x: Directory => x }
  def files: Iterator[File] = list collect { case x: File => x }
  
  override def walkFilter(cond: Path => Boolean): Iterator[Path] =
    list filter cond flatMap (_ walkFilter cond)

  def deepDirs: Iterator[Directory] = Path.onlyDirs(deepList())
  def deepFiles: Iterator[File] = Path.onlyFiles(deepList())
  
  /** If optional depth argument is not given, will recurse
   *  until it runs out of contents.
   */
  def deepList(depth: Int = -1): Iterator[Path] =
    if (depth < 0) list ++ (dirs flatMap (_ deepList (depth)))
    else if (depth == 0) Iterator.empty
    else list ++ (dirs flatMap (_ deepList (depth - 1)))
  
  /** An iterator over the directories underneath this directory,
   *  to the (optionally) given depth.
   */
  def subdirs(depth: Int = 1): Iterator[Directory] = 
    deepList(depth) collect { case x: Directory => x }
}