Famous 4th thread.

Question about the task

Under discussion

I tried many ways from former questions in this topic, and I don't know, maybe something wrong with creating threads in Solution class, or inheritance?

1. Create 5 different threads that differ from Thread:
1.1. Thread 1 must run indefinitely;
1.2. Thread 2 should display "InterruptedException" when an InterruptedException occurs;
1.3. Thread 3 should display "Hurray" every half second";
1.4. Thread 4 must implement the Message interface. When the showWarning method is called, the thread should stop;
1.5. Thread 5 should read numbers from the console until "N" is entered. Then it should display the sum of the entered numbers.
2. In a static block, add your threads to List<Thread> threads in the specified order.
3. The threads should not start automatically.

Hint:
Thread 4 can be checked using isAlive()

Requirements:

The Solution class's static block must create 5 threads and add them to the threads list.
The threads in the threads list should not start automatically.
Thread 1 in the threads list must run infinitely.
Thread 2 in the threads list should display "InterruptedException" when an InterruptedException occurs.
Thread 3 in the threads list should display "Hurray" every half second.
Thread 4 in the threads list must implement the Message interface. When the showWarning method is called, the thread should stop.
Thread 5 in the threads list should read numbers from the console until "N" is entered. Then it should display the sum of the entered numbers.

package com.codegym.task.task16.task1632; public interface Message { void showWarning(); }

Comments (5)

Popular
New
Old

You must be signed in to leave a comment

Thomas

Level 41 , Bayreuth, Germany

11 January 2023, 16:35

useful

maybe try to make isWarned volatile

matemate123

Level 50 , Kraków, Poland

11 January 2023, 19:07

not working too

matemate123

Level 50 , Kraków, Poland

11 January 2023, 19:19

Ok it's weird task. I changed in solution for simpler

Thread1 thread1 = new Thread1();
Thread2 thread2 = new Thread2();
Thread3 thread3 = new Thread3();
Thread4 thread4 = new Thread4();
Thread5 thread5 = new Thread5();

Then verificator accept my 4th thread but 2th was on red. I change (in Thread2) run (!isInterrupted) for (isAlive()) and now we talking!

Thomas

Level 41 , Bayreuth, Germany

12 January 2023, 07:48

for thread 2, I'd just use an infinity loop using true instead (that's what I actually did in my solution ;) ). Your original one has a minimal possibility that sending an interrupt is not causing the exception (that's when the task gets interrupted exactly when your thread is testing the while condition - In that case the sleep method won't throw the exception and the task ends regularly).

matemate123

Level 50 , Kraków, Poland

12 January 2023, 11:47

Yea probably 1/1000 , 10/1000 posibility? It's crazy with that threads, I suppose after month it'll be easier to grasp the understanding.