public class System1 {
    public void dosomething() {
        System.out.println("system1..");
    }
}

public class System2 {
    public void dosomething() {
        System.out.println("system2..");
    }
}

public class Facade {
    System1 system1 = new System1();
    System2 system2 = new System2();
    public void dosomething() {
        system1.dosomething();
        system2.dosomething();
    }
}

public class Client1 {
    public static void main(String[] args) {
        Client1 client1 = new Client1();
        client1.dosomething();
    }

    public void dosomething() {
        Facade facade = new Facade();
        facade.dosomething();
    }
}

public class Client2 {
    public static void main(String[] args) {
        Client2 client2 = new Client2();
        client2.dosomething();
    }

    public void dosomething() {
        Facade facade = new Facade();
        facade.dosomething();
    }
}