There is a key design patterns that are used in the code above. State the pattern and describe which classes play which roles in the pattern. Also Draw a class diagram depicting the classes and their relationships.

Beef.java

public class Beef implements Protein $\{$

public String add$()\{$

return "Protein added is Beef";

$\}$

$\}$

BeefDish.java

public class BeefDish extends Food $\{$

public BeefDish$($Protein protein$)\{$

super$($protein$)$;

$\}$

@Override

public String cook$()\{$

return "BeefDish cooked. $"+$ protein.add$()$;

$\}$

$\}$

Chicken.java

public class Chicken implements Protein $\{$

public String add$()\{$

return "Protein added is Chicken";

$\}$

$\}$

ChickenDish.java

public class ChickenDish extends Food $\{$

public ChickenDish$($Protein protein$)\{$

super$($protein$)$;

$\}$

@Override

public String cook$()\{$

return "ChickenDish cooked. $"+$ protein.add$()$;

$\}$

$\}$

Food.java

public abstract class Food $\{$

protected Protein protein;

$//$standard constructors

abstract public String cook$()$;

public Food$($Protein protein$)\{$

this.protein $=$ protein;

$\}$

$\}$

Protein.java

public interface Protein $\{$

String add$()$;

$\}$

Test.java

public class Test $\{$

public static void main$($String$[]$ args$)\{$

$//$a dish with beef

Food dish$1=$ new BeefDish$($new Beef$())$;

System.out.println$($dish$1.$cook$())$;

$//$a dish with protein

Food dish$2=$ new ChickenDish$($new Chicken$())$;

System.out.println$($dish$2.$cook$())$;

$\}$

$\}$