Temptations of Scala…

March 14, 2014

As I continue my romance with Scala language, I decided to take up the rubber duck code from Head First Design Patterns. The code already is implemented using Strategy pattern as we know. Just check the C# code juxtaposed against the Scala code, (dont ask which one is C# code)

class Program
{
    static void Main(string[] args)
    {
        var actualDuck = new Duck(new ActualFlyBehavior(), 
                               new ActualQuackBehavior());
        actualDuck.DoFly();
        actualDuck.DoQuack();
        var rubberDuck = new Duck(new NoFlyBehavior(), 
                                 new NoQuackBehavior());
        rubberDuck.DoFly();
        rubberDuck.DoQuack();
        Console.ReadLine();
    }
}

public class ActualFlyBehavior : IFly
{
    public void Fly()
    {
        Console.WriteLine("I am actually flying!!!");
    }
}

public class ActualQuackBehavior : IQuack
{
    public void Quack()
    {
        Console.WriteLine("I am actually quacking!!!");
    }
}

public class NoFlyBehavior : IFly
{
    public void Fly()
    {
        Console.WriteLine("---");
    }
}

public class NoQuackBehavior : IQuack
{
    public void Quack()
    {
        Console.WriteLine("---");
    }
}

public class Duck
{
    private readonly IFly fly;
    private readonly IQuack quack;

    public Duck(IFly fly, IQuack quack)
    {
        this.fly = fly;
        this.quack = quack;
    }

    public void DoFly()
    {
        fly.Fly();
    }

    public void DoQuack()
    {
        quack.Quack();
    }
}

public interface IFly
{
    void Fly();
}

public interface IQuack
{
    void Quack();
}

object Starter extends App
{
  println("Hello World!!!")
  val actualDuck = new ActualDuck
  actualDuck.doFly()
  actualDuck.doQuack()
  val rubberDuck = new RubberDuck
  rubberDuck.doFly()
  rubberDuck.doQuack()
}

abstract class Duck
{
  def doFly()
  def doQuack()
}


class ActualDuck extends Duck with Fly with Quack
{

}

class RubberDuck extends Duck
{
  def doFly() {println("---")}
  def doQuack() {println("---")}
}

trait Fly
{
  def doFly(){println("I am actually flying!!!")}     
}

trait Quack
{
  def doQuack(){println("I am actually quacking!!!")}  
}

Temptations of Scala…

Abhang Rane

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