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Question about the task

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1. Figure out what the program does.
2. Implement logic in the printCountdown method so that every half a second the program displays an object from the variable list. The output should be in reverse order: from the index passed to Countdown down to zero.

Example:
Index 3 is passed

Example console output:
Line 2 Line 1 Line 0

Requirements:

The printCountdown method should run for about half a second.
The printCountdown method should reduce (decrement) the value of the variable countFrom.
The printCountdown method must display the list item with an index equal to the new value of countFrom.
The main method must create a Countdown object.
The program's output must match the example in the task conditions.

package com.codegym.task.task16.task1614; import java.util.ArrayList; import java.util.List; /* Countdown */ public class Solution { public static volatile List<String> list = new ArrayList<>(5); static { for (int i = 0; i < 5; i++) { list.add("Line " + i); } } public static void main(String[] args) throws InterruptedException { Thread t = new Thread(new Countdown(3), "Countdown"); t.start(); } public static class Countdown implements Runnable { private int countFrom; public Countdown(int countFrom) { this.countFrom = countFrom; } public void run() { try { while (countFrom > 0) { printCountdown(); } } catch (InterruptedException e) { } } public void printCountdown() throws InterruptedException { //write your code here Thread.sleep(500); while(true) { countFrom--; System.out.println(Solution.list.get(countFrom)); if(this.countFrom==0) break; } } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

14 April 2019, 16:19

solution

Your logic is a little jumbled. #1a) line 34 already places the printCountdown method in a while loop, you do not need a loop inside the method. #1b) line 34 already has a condition that breaks the loop when there are no more things to print, make sure you also remove the 'break' inside the method along with the loop it breaks. #2) you want it to print to screen every half second, which you do accomplish, however your sleep should occur after the first print, not before.

Satya Vath

Level 31 , Vijayawada, India

16 April 2019, 12:38

Thanks For Your Support Gagnon

Mateo

Level 26 , Zagreb, Croatia

1 July 2019, 09:26

Guadalupe is CodeGyms MVP!