Help a brother out.

Question about the task

Fix four mistakes

Java Core, Level 4, Lesson 8

Under discussion

The error "The initList method must fill the resulting list with random values". Any hints?

1. Think about what the main method does.
2. Create static methods initList(List<Number> list), printListValues(List<Number> list), and processCastObjects(List<Number> list) in the Solution class.
3. Find the block of code that fills the list with values and move it to the initList method.
4. Find the block of code that uses a for loop to display the contents of the list, and move it to the printListValues method.
5. Find the block of code that checks the type of each object of the list and displays messages on the screen, and move it to the processCastObjects method.
6. Correct 2 bugs in the printListValues method so that the method correctly displays the contents of the list passed as an argument.
7. Correct 2 bugs related to type casting in the processCastObjects method
- for a Float object, you need to display "Is float defined? " + !(<Float object>.isNaN()).
- for a Double object, you need to print "Is double infinite? " + <Double object>.isInfinite().

Requirements:

The Solution class must implement static methods initList(List<Number> list), printListValues(List<Number> list), and processCastObjects(List<Number> list).
The initList method must fill the resulting list with random values.
The printListValues method should display the contents of the resulting list.
The processCastObjects method should analyze the list items and display text for Float and Double objects in accordance with the task conditions.

package com.codegym.task.task14.task1418; import java.util.LinkedList; import java.util.List; /* Fix four mistakes */ public class Solution { public static void main(String[] args) { List<Number> list = initList(new LinkedList<> ()); printListValues(list); processCastObjects(list); } public static List<Number> initList(List<Number> list) { List<Number> list1 = new LinkedList<>(); // 3 list1.add(new Double(1000f)); list1.add(new Double("123e-445632")); list1.add(new Float(-90 / -3)); list1.remove(new Double("123e-445632")); return list1; } public static void printListValues(List<Number> list) { // 4 - Correct 2 bugs for (int i = 0; i < list.size(); i++) { System.out.println(list.get(i)); } } public static void processCastObjects(List<Number> list) { // 5 for (Number object : list) { // Correct 2 bugs if (object instanceof Float) { Float a = (Float) object; System.out.println("Is float defined? " + !(a.isNaN())); } else if (object instanceof Double) { Double a = (Double) object; System.out.println("Is double infinite? " + a.isInfinite()); } } } }

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Rich

Level 23 , San Diego, United States

17 November 2020, 00:20

find the three required segments, make the three helper methods outside if main, move them to the correct method and debug

Joy Majumdar

Level 16 , Kolkata, India

29 July 2019, 10:38

Put those actions what you see by creating the mentioned methods given in the conditions i.e. in Solution class create the method() { copy those stuff here }

yz Backend Developer

12 July 2019, 10:57

u should already have created list and then add that list to the method(initList) which then adds some random values. List list = new List(); initList(list){ list.add(); } the method on;y adds not creates

Hashirama

Level 26 , Port-Harcourt, Nigeria

6 February 2019, 12:51

Your return type should be void for all the methods because we don't need to return anything. 1. The first method that adds elements adds them to the list you pass as argument 2. The second method prints every element from the list you pass as argument 3. The third method makes those decisions from the list you pass as argument.

Roman

Level 41

16 November 2018, 11:18

In the initList(List list) method you should fill the list which is a argument of the method.