I get timeout

Question about the task

Restaurant (part 22)

Java Multithreading, Level 9, Lesson 15

Under discussion

I have no clue what is wrong. I get timeout.

Unfortunately, the orders are still not being prepared in parallel. Here's how our thread from the previous task works.
It finds a cook, finds an order, gives the order to the cook using the startCookingOrder method, waits for the order to be prepared, and only then moves on to the next order. This is because all the actions are performed consecutively on a single thread. We can't perform actions in parallel on the same thread.
We need a standard Producer-Consumer implementation.
RandomOrderGeneratorTask is our Producer, because it makes orders.
Cook is the Consumer, because it processes orders.

1. Move the queue from OrderManager to Restaurant, and make it a private constant.
2. Add a queue field and setter to the Cook class. Immediately after creating a cook, use the created setter to set the created field equal to the constant from item 1.
3. Tablet should not be an Observable. Remove all the dependencies.
4. In Tablet, create a setter and set a reference to the queue (item 1) a tablet is created.
5. In Tablet, replace the logic that notifies the Observer with logic that adds the order to the queue.
6. In the method main, create and run threads based on Cook tasks.
7. Remove the cooks set, its getter, and the register(Cook cook) method from the StatisticsManager class.
8. Make the Cook class a task (Runnable). Move the logic from the thread in the OrderManager constructor to the Cook class's run method.
9. Remove the OrderManager class and fix the Observer-Observable relationship in the main method.

Requirements:

A private final static LinkedBlockingQueue orderQueue field must be created in the Restaurant class.
A private LinkedBlockingQueue queue field and corresponding setter must be created in the Cook class.
A private LinkedBlockingQueue queue field must be created in the Tablet class.
The Tablet class not must be a descendant of the Observable class.
The Cook class should support the Runnable interface.
The general logic of order preparation and displaying ads must be preserved.
The OrderManager class should be deleted.

package com.codegym.task.task27.task2712; import com.codegym.task.task27.task2712.kitchen.Cook; import com.codegym.task.task27.task2712.kitchen.Order; import com.codegym.task.task27.task2712.kitchen.Waiter; import java.util.ArrayList; import java.util.List; import java.util.concurrent.LinkedBlockingQueue; public class Restaurant { private static final int ORDER_CREATION_INTERVAL = 100; private static final LinkedBlockingQueue<Order> orderQueue = new LinkedBlockingQueue<>(); public static void main(String[] args) throws Exception { Cook cook1 = new Cook("Amigo"); Cook cook2 = new Cook("Diego"); cook1.setQueue(orderQueue); cook2.setQueue(orderQueue); Waiter waiter = new Waiter(); cook1.addObserver(waiter); cook2.addObserver(waiter); List<Tablet> tablets = new ArrayList<>(); for (int i = 1; i <= 5; i++) { Tablet tablet = new Tablet(i); tablets.add(tablet); tablet.setQueue(orderQueue); } Thread cookThread1 = new Thread(cook1); cookThread1.start(); Thread cookThread2 = new Thread(cook2); cookThread2.start(); RandomOrderGeneratorTask randomOrderGeneratorTask = new RandomOrderGeneratorTask(tablets, ORDER_CREATION_INTERVAL); Thread thread = new Thread(randomOrderGeneratorTask); thread.start(); Thread.sleep(1000); thread.interrupt(); cookThread1.interrupt(); cookThread2.interrupt(); } }

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AnnemiekFF

Level 41 , Breda, Netherlands

21 April 2020, 09:17

You don't have to call interrupt on the cookThread.