Time out error when trying to validate

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The program creates the expected output. When trying to validate I'm running into a time out error though. ("Check your code. It looks like you have an infinite loop.") I explicitly added Thread.currentThread().interrupt(); in the catch clauses of the InterruptedExceptions in order to kind of "rethrow" the interrupt. (I also tried using boolean flags beforehand.) When sending the interrupt from the main method the program successfully stops running. I'm therefore not sure what the issue is. Any hints are much appreciated. :-) Cheers Seb

1. Create a Producer and Consumer (See the comments on the main method).

2. Create toString, equals, and hashCode methods in the SharedItem class. To do this in IntelliJ IDEA, do the following in the body of the SharedItem class:
2.1. Alt+Insert -> toString() -> Enter.
2.2. Alt+Insert -> equals() and hashCode() -> click 'Next' every time.
2.3. Leave IntelliJ IDEA's implementation of the toString(), equals(), and hashCode() methods as it is.

3. In Producer and Consumer, implement the run method so that calling the interrupt method interrupts the consumer and producer threads.

4. Implement the Producer's run method:
4.1. Using the offer method, add 9 SharedItems to the queue, with the following arguments: ("SharedItem-N", N), where N is a item number from 1 to 9.
4.2. Before each addition, display the phrase "'SharedItem-N' added". Use System.out.format.
4.3. Put the thread to sleep for 0.1 seconds.
4.4. If the queue has a Consumer that is not busy working, then display the phrase "Consumer is waiting!".
Take a look at the methods of the TransferQueue interface. You'll find the method you need.

5. Implement the Consumer's run method:
5.1. Put the thread to sleep for 0.45 seconds.
5.2. In an infinite loop, use the take method to get an item from the queue and display "Processing item.toString()".

6. Check the output against the output.txt file.

7. Don't display the stack trace on the console.

8. Use System.out.format to display any information on the screen.

Requirements:

Create a Producer class.
Create a Consumer class.
The following methods must be created in the SharedItem class: toString(), equals(Object), and hashCode().
The Producer class's run() method must be implemented according to the task conditions.
The Consumer class's run() method must be implemented according to the task conditions.
The output should match the output.txt file.

package com.codegym.task.task30.task3003; import java.util.concurrent.LinkedTransferQueue; import java.util.concurrent.TransferQueue; /* Saving time */ public class Solution { /* 1. Create a Producer class. To do this, click Alt+Enter -> Create Class... on the red class name. 2. Point at the parameter name in the constructor (queue) and click Alt+Enter -> Create Field for Parameter 'queue' -> Enter -> Enter. The field name is queue. 3. Point at the underlined class description. Then Alt+Enter -> Implement Methods -> Enter. 4. Do items 1-3 for the Consumer class. */ public static void main(String[] args) throws InterruptedException { TransferQueue<SharedItem> queue = new LinkedTransferQueue<>(); Thread producer = new Thread(new Producer(queue)); Thread consumer = new Thread(new Consumer(queue)); producer.start(); consumer.start(); Thread.sleep(1500); producer.interrupt(); consumer.interrupt(); } }

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ABDOULRAHMAN ADEN DAHER

Level 31 , DJBOUTI, Djibouti

9 February, 11:29

import java.util.concurrent.TransferQueue;
public class Consumer implements Runnable {

     private final TransferQueue<SharedItem> queue;

    public Consumer(TransferQueue<SharedItem> queue) {
        this.queue = queue;
    }

    @Override
    public void run() {
        try {
            Thread.sleep(450);
            while (!Thread.currentThread().isInterrupted()) {
                SharedItem sharedItem = queue.take();
                System.out.format("Processing %s%n", sharedItem);
            }
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }

}

ABDOULRAHMAN ADEN DAHER

Level 31 , DJBOUTI, Djibouti

9 February, 11:29

import java.util.concurrent.TransferQueue;
public class Producer implements Runnable{



   private final TransferQueue<SharedItem> queue;

    public Producer(TransferQueue<SharedItem> queue) {
        this.queue = queue;
    }

    @Override
    public void run() {
        try {
            for (int i = 1; i <= 9; i++) {
                SharedItem sharedItem = new SharedItem("SharedItem-" + i, i);
                System.out.format("'SharedItem-%d' added%n", i);
             //   System.out.format("'%s' added%n", sharedItem.getDescription());
                queue.offer(sharedItem);
                Thread.sleep(100);
                if (queue.hasWaitingConsumer()) {
                     System.out.format("Consumer is waiting!%n");
                   // System.out.println("Consumer is waiting!");
                }
            }
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    }


}

Seb

Level 41 , Crefeld, Germany

14 February 2020, 22:48

Alrighty, thanks to the help of Evghenii, I've finally been able to solve this task... :-P :-) The time out error was basically created due to all those extra try-catch blocks. It's sufficient to wrap the whole run method in one try-catch block - catching InterruptedException and leaving the catch block empty. That way the producer.interrupt() and the consumer.interrupt() called in the main method, stop the run methods already. That's pretty much it.