SP - Command Pattern

package ZCOMM1;

// Задатак ZCOMM1: Додати програм на месту три тачке како би се добила порука:
// Danas je lep dan.

class Client{
    Receiver rec;
    Command cm;

    Client(){
        rec = new Receiver();
        cm = new ConcreteCommand(rec);
    }

    Command getCommand(){return cm;}
    public static void main(String[] args) {
        Client cl = new Client();
        Invoker inv = new Invoker(new ConcreteCommand(cl.rec));
        inv.Execute();
    }
}

class Invoker{
    Command com;

    Invoker(Command com1) {
        com = com1;
    }

    void Execute() {
       com.Execute();
    }
}

interface Command{
  void Execute();
}

class ConcreteCommand implements Command{
    Receiver rec;

    ConcreteCommand(Receiver rec1) {
        rec = rec1;
    }

    @Override
    public void Execute() {
        rec.Action();
    }
}

class Receiver{
    void Action(){System.out.println("Danas je lep dan.");}
}