CODESAMPLE

Facade - Scala

Facade Scala

The Facade pattern provides a simplified interface to a complex subsystem. It encapsulates multiple interactions within the subsystem into a single, higher-level interface, making it easier for clients to use. This example demonstrates a media player facade, hiding the complexities of audio and video processing. The MediaFacade class offers simple playMovie and playMusic methods, internally coordinating the AudioPlayer, VideoPlayer, and Codec components. This implementation is idiomatic Scala due to its use of classes for encapsulation, clear method signatures, and concise code leveraging Scala’s features.

// Subsystem classes
class AudioPlayer {
  def play(audioType: String, fileName: String): Unit = {
    println(s"Playing audio file: $fileName (Type: $audioType)")
  }
}

class VideoPlayer {
  def play(fileName: String): Unit = {
    println(s"Playing video file: $fileName")
  }
}

class Codec {
  def convert(fileType: String, fileName: String): String = {
    println(s"Converting file: $fileName (Type: $fileType)")
    fileName // Simulate conversion - return the same name
  }
}

// Facade class
class MediaFacade {
  private val audioPlayer = new AudioPlayer()
  private val videoPlayer = new VideoPlayer()
  private val codec = new Codec()

  def playMovie(fileName: String): Unit = {
    val convertedFileName = codec.convert("mp4", fileName)
    videoPlayer.play(convertedFileName)
  }

  def playMusic(fileName: String): Unit = {
    val convertedFileName = codec.convert("mp3", fileName)
    audioPlayer.play("mp3", convertedFileName)
  }
}

// Client code
object Main {
  def main(args: Array[String]): Unit = {
    val mediaFacade = new MediaFacade()

    mediaFacade.playMovie("movie.avi")
    mediaFacade.playMusic("song.wav")
  }
}