I think the problem is with the constructor. HELP PLIZ

Question about the task

Refactoring the Chain of Responsibility pattern

Java Multithreading, Level 9, Lesson 9

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when i remove the level field, the constructors crash, and i need them to make it verify. what's the solution?

We have a program that has a logging system that works as follows:
- if the event's log level is FATAL, the manager is called, the CEO receives an SMS, a message is displayed on the console, and an entry is made in the log file;
- if the event's log level is ERROR, the CEO receives an SMS, a message is displayed on the console, and an entry is made in the log file;
- if the event's log level is WARN, a message is displayed on the console and an entry is made in the log file;
- if the event's log level is INFO, a log entry is made in the log file.

The program implements the "chain of responsibility" pattern. Study it carefully. The FileLogger, ConsoleLogger, SmsLogger, and PhoneLogger classes have a lot of duplicate code. Pull all the duplicate code up to an AbstractLogger abstract class.
In refactoring, pulling up means to move fields, methods, constructors from all child classes into one common parent class. In doing so, the code that is moved to the parent class is removed from the child classes.

The program's behavior should not change.

Requirements:

The AbstractLogger class must be abstract.
The AbstractLogger class must support the Logger interface.
You must pull the level and next fields up to the AbstractLogger class.
You need to pull the setNext(Logger) and inform(String, int) methods up to the AbstractLogger class.
The program's output should remain unchanged.

package com.codegym.task.task29.task2912; /* Refactoring the Chain of Responsibility pattern */ public class Solution { public static void main(String[] args) { Logger logger3 = (Logger) new PhoneLogger(Level.FATAL); Logger logger2 = (Logger) new SmsLogger(Level.ERROR); Logger logger1 = (Logger) new ConsoleLogger(Level.WARN); Logger logger0 = (Logger) new FileLogger(Level.INFO); logger3.setNext(logger2); logger2.setNext(logger1); logger1.setNext(logger0); logger3.inform("Everything is OK", Level.INFO); logger3.inform("We found a bug", Level.WARN); logger3.inform("Database connection error", Level.ERROR); logger3.inform("System shut down", Level.FATAL); } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

19 August 2020, 13:37

solution

#1 the child classes need to inherit from the parent class. #2 when that is complete, you should put a constructor in the AbstractLogger class that sets level. When a parent class has only non-default constructors this will force any child classes to call super() in any of its constructors with arguments that match one of the parent classes constructors. It is a common mistake to not do this and have a child class error out because when an object is created it is only partially initialized. If you are unable to fix the code from these tips (maybe you forget how the original code was), reset the task. It will take 2 minutes to create an AbstractLogger class and copy/paste the code from one of the other classes in.

Henrique

Level 41 , São Paulo, Brazil

19 August 2020, 14:12

Thanks, man! That solved the problem. The silly mistake of forgetting to inherit te parent class (how could I forget that??? 😡) caused me all the problems, and I thought the problem was elsewhere.

Guadalupe Gagnon

Level 37 , Tampa, United States

19 August 2020, 14:15

I've made plenty of silly mistakes on my journey through learning how to program too. I tell people all the time that mistakes are the best way to learn.