I've got a strange message

Question about the task

List of number arrays

Java Syntax, Level 9, Lesson 11

Under discussion

I've got a strange message: The task does not compile on the server! Though it is working as intended in IJ.

Create a list whose elements are arrays of numbers.
Add to the list five array objects whose lengths are 5, 2, 4, 7, and 0, respectively.
Fill the arrays with any data and display them on the screen.

Requirements:

The program must not read data from the keyboard.
The createList method must declare and initialize an ArrayList<int[]> variable.
The createList method must return the created list.
The createList method must add 5 elements to the list.
Each element in the list must be an array of numbers. The length of the first array must be 5; the second — 2; and the rest — 4, 7, and 0, respectively.
The program should display the elements of all the arrays in the list. Each element on a new line.

package com.codegym.task.task09.task0926; import java.util.ArrayList; import java.util.List; /* List of number arrays */ public class Solution { public static void main(String[] args) { ArrayList<int[]> list = createList(); printList(list); } public static ArrayList<int[]> createList() { return new ArrayList<int[]>(List.of(fillArr(5), fillArr(2), fillArr(4), fillArr(7), fillArr(0))); } public static void printList(ArrayList<int[]> list) { for (int[] array : list) { for (int x : array) { System.out.println(x); } } } static int[] fillArr(int l) { int[] arr = new int[l]; for (int i = 0; i < arr.length; i++) { arr[i] = i; } return arr; } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

11 November 2020, 15:03

What Nouser said is true. You should set the language in intelliJ to Java 8 so you don't use constructs/methods created in later versions that won't compile on the server. Go to File > project structure next select Modules then, for each Module, set the Language Level to 8 See picture below:

Dmitri

Level 22 , Seversk, Russia

12 November 2020, 11:57

Thank you!

Nouser

Level 36 , Germany

11 November 2020, 12:33

useful

For List.of you need Java 9+ and afaik the validation uses Java 8. Instead you could try something with Arrays.asList, not as beautiful but... OK

//create a two dim array
int[][] tempTestArr = new int[][]{fillArr(4), fillArr(5), fillArr(6), fillArr(7)};
//save the array in a list
List<int[]> testList = Arrays.asList(tempTestArr);
//if necessary, the list can be given to an ArrayList
ArrayList<int[]> finalArrayList = new ArrayList<>(testList);

//all in one line
//ArrayList<int[]> finalArrayList = new ArrayList<>(Arrays.asList(new int[][]{fillArr(4), fillArr(5), fillArr(6), fillArr(7)}));

Dmitri

Level 22 , Seversk, Russia

12 November 2020, 11:57

Thank you!