Why is this not validating and giving an error (the only one) for my update method in the Waiter class?

Question about the task

Under discussion

@Override
    public void update(Observable o, Object arg) {
        this.order = (Order) arg;
        System.out.println(this + " was prepared by " + o);
    }

What do we have? The cook has prepared the dishes. It's time to take them away, but the waiter is unaware.
We need to notify the waiter that it's time to pick up the order from the kitchen.
This situation is similar to the previous task, so we'll use the Observer pattern again.

1. Create a Waiter class in the kitchen package. It will carry the orders back to the table. The waiter won't have a name.

2. Cook prepares orders, and Waiter processes them. Properly assign Observer and Observable to Waiter and Cook.

3. The void update method will display a message about the order and who prepared it:
order + " was prepared by " + cook

4. In the class that inherits Observable, we'll do the following before sending an order:
4.1. Set the flag using setChanged()
4.2. Send the order to the observer using notifyObservers(order);

5. Let's write the main method.
For the Observable object, add our own Observer object. See item 2 and the description of the pattern in Wikipedia
We give the cook a name. The name doesn't affect the tests. In my version, the cook's name is Amigo. :)

Let's check the console output. Example of my output:

Your order: [Water] from Tablet{number=5}
Start cooking - Your order: [Water] from Tablet{number=5}

Your order: [Water] from Tablet{number=5} was prepared by Amigo

Requirements:

The Waiter class must implement the Observer interface.
The Cook class must be a descendant of the Observable class.
The Cook class's update method must call the setChanged method.
The Cook class's update method must call the notifyObservers method with the current order as the argument.
The Waiter class's update method should display a string formatted according to the task conditions.
The Restaurant class's main method should create a new waiter and use the addObserver method to add it the cook as an observer.

package com.codegym.task.task27.task2712; import com.codegym.task.task27.task2712.kitchen.Cook; import com.codegym.task.task27.task2712.kitchen.Waiter; public class Restaurant { public static void main(String[] args) { Tablet tablet = new Tablet(1); Cook cook = new Cook("Rondereo"); tablet.addObserver(cook); Waiter waiter = new Waiter(); cook.addObserver(waiter); tablet.createOrder(); // tablet.createOrder(); // tablet.createOrder(); // tablet.createOrder(); } }

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matemate123

Level 50 , Kraków, Poland

16 July 2023, 07:11

This line is unnecessary, and someone encountered an issue with a similar casting in the previous step.

this.order = (Order) arg;

Using toString() method is nice to see by Validator.

arg.toString ...  o.toString

Guadalupe Gagnon

Level 37 , Tampa, United States

12 December 2022, 21:51

Try using ConsoleHelper