It is showing error after i remove a method in CTO class

Question about the task

Parent of the CTO class

Java Core, Level 2, Lesson 12

Under discussion

it is showing error after i remove the method workHard from CTO class how can i solve this

Add a parent class to the CTO class so that the class isn't abstract.
You can't add or implement any methods in the CTO class.

Requirements:

The Solution class must have a Businessman interface with a void workHard() method.
The Solution class must have a non-abstract CTO class.
The CTO class must implement the Businessman interface.
The CTO class must not have any methods.
The Solution class must have one additional class.
The CTO class must inherit the additional class.
The additional class must have one method.

package com.codegym.task.task12.task1229; /* Parent of the CTO class */ public class Solution { public static void main(String[] args) { CTO cto = new CTO(); System.out.println(cto); } abstract static public class h{ abstract public void workHard(); } public static interface Businessman { public void workHard(); } public static class CTO extends h implements Businessman { public void workHard(){} } }

Comments (5)

Popular
New
Old

You must be signed in to leave a comment

Paravoffka

Level 18 , Vancouver, Canada

15 September 2019, 00:43

1) additionalOne implements Businessman 2) CTO extends additionalOne implements Businessman Done.

Guadalupe Gagnon

Level 37 , Tampa, United States

7 February 2019, 14:44

So a couple of things to help you solve this: #1 An interface is just a blueprint of methods that are absolutely going to be included in any class that implements that interface. #2 The abstract keyword on a method in a parent class functions almost the same way as above. This says that the class where the method is located will not have the code to run the method, but any class that extends this class will implement this method. Once you are able to figure out which class should implement businessman, and subsequently not make the method(s) abstract, you will be able to safely remove the workHard method from the CTO class.

Anoop Negi

Level 15 , Meerut, India

8 February 2019, 14:42

ok i removed abstract from class h then it worked but the question is why and how it worked can you tell please

Guadalupe Gagnon

Level 37 , Tampa, United States

8 February 2019, 14:49

do you mean that you removed abstract from the workHard method in class H? This is because abstract on a method is telling the compiler that the method in that class will have no body of code, however in any extended classes the method will be implemented. So the workHard in class h, at first writing, had the abstract modifier on it, and CTO extended class h, so that meant that workHard had to be implemented in CTO. When you removed that keyword, and subsequently implemented in h by adding { }, you now no longer needed to add it to CTO. It is still in CTO, as all methods are inherited, just not implemented in CTO. In the main method you can call the workHard() method on the cto object that is created, proving that it is in fact there.

ddi

Level 18 , Dortmund, Germany

8 August 2019, 14:21

Took me an hour to do this exercise but with both of your ideas is done. the additional class creates the workHard method the Businessmann calls it and the Cto implements it! took me a bit to get it :)