Can't see my mistake

Question about the task

Under discussion

Any help would be much appreciated. It says that "The readKeyFromConsoleAndInitPlanet method must be called in the Solution class's static block." when it clearly is, as are all of the unmet conditions.Especially the last condition which is all of the classes to be in different files :/

1. Find an example of the singleton pattern used for lazy initialization. Use your favorite search engine (such as Google).
2. In separate files, create three singleton classes in its likeness and image: Sun, Moon, and Earth.
3. Implement the Planet interface in the Sun, Moon, and Earth classes.
4. In Solution class's static block, call the readKeyFromConsoleAndInitPlanet method.
5. Implement the readKeyFromConsoleAndInitPlanet method:
5.1. Read one String value from the console.
5.2. If the value is equal to one of the Planet interface's constants, create a corresponding object and assign it to Planet thePlanet, otherwise set the Planet thePlanet to null.

Requirements:

The Sun class should prevent Sun objects from being created outside the class.
The Sun class must have a private static Sun field named instance.
The Sun class must implement the public static getInstance method, which returns the value of the field instance.
The Sun class's getInstance method must ALWAYS return the same object.
The field instance must be initialized after the first call to the getInstance method, but not before.
The Moon class should prevent Moon objects from being created outside the class.
The Moon class must have a private static Moon field instance.
The Moon class must implement the public static getInstance method, which returns the value of the field instance.
The Moon class's getInstance method must ALWAYS return the same object.
The field instance must be initialized after the first call to the getInstance method, but not before.
The Earth class should prevent Earth objects from being created outside the class.
The Earth class must have a private static Earth field instance.
The Earth class must implement the public static getInstance method, which returns the value of the field instance.
The Earth class's getInstance method must ALWAYS return the same object.
The field instance must be initialized after the first call to the getInstance method, but not before.
The readKeyFromConsoleAndInitPlanet method must be called in the Solution class's static block.
The readKeyFromConsoleAndInitPlanet method should read one line from the keyboard.
The readKeyFromConsoleAndInitPlanet method must correctly update the value of the variable thePlanet according to the task conditions.
The Sun, Moon and Earth classes must be in separate files.

package com.codegym.task.task15.task1522; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; /* Reinforce the singleton pattern */ public class Solution { public static void main(String[] args) { } public static Planet thePlanet; // Add static block here static { try { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); readKeyFromConsoleAndInitPlanet(br.readLine()); } catch (IOException e) { System.out.println("Not a legit planet"); } } public static void readKeyFromConsoleAndInitPlanet(String thePlanet1) { // Implement step #5 here if (thePlanet1.equals("earth")) thePlanet = Earth.getInstance(); else if (thePlanet1.equals("moon")) thePlanet = Moon.getInstance(); else if (thePlanet1.equals("sun")) thePlanet = Sun.getInstance(); else thePlanet = null; } }

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hacks patel

Level 20 , Ahmedabad, India

30 May 2019, 09:34

BufferedReader r = new BufferedReader(new InputStreamReader(System.in)); try { String s = r.readLine(); if(s.equals(Planet.EARTH)){ thePlanet = Earth.getInstance(); } else if(s.equals(Planet.MOON)){ thePlanet = Moon.getInstance(); } else if(s.equals(Planet.SUN)){ thePlanet = Sun.getInstance(); } else { thePlanet = null; } } catch (IOException e){ } //try something like this

Bill Wu

Level 29 , Wellington, New Zealand

17 May 2019, 06:16

1. getInstance() should be synchronized; 2. readKeyFromConsoleAndInitPlanet() shouldn't have parameters, just make the reading string inside the method. Hopefully that helps.

Darko Jakimovski

Level 18 , Kriva Palanka, Macedonia, The Former Yugoslav Republic of

17 May 2019, 09:24

Thanks Bill

Guadalupe Gagnon

Level 37 , Tampa, United States

17 May 2019, 14:03

Good catch. I didn't even notice the readKeyFromConsoleAndInitPlanet method had no parameters to start with, but it makes sense when reading the method name.

Darko Jakimovski

Level 18 , Kriva Palanka, Macedonia, The Former Yugoslav Republic of

20 May 2019, 10:44

I finished this one at last. My logic with setting thePlanet to null was also flawed, it threw a NullPointerException :) Thanks guys. Tripple OG's :D

Guadalupe Gagnon

Level 37 , Tampa, United States

15 May 2019, 19:29

Take a look at Sun, Moon, and Earth class. There is something different with Sun and Moon that you are not doing in Earth. Start there and see if verification passes.

Darko Jakimovski

Level 18 , Kriva Palanka, Macedonia, The Former Yugoslav Republic of

16 May 2019, 08:02

That helped for the last two conditions, but how am I not calling readKeyFromConsoleAndInitPlanet in the static block? Btw how are the higher lvls? Having fun? You've melted them in record time :D

Guadalupe Gagnon

Level 37 , Tampa, United States

16 May 2019, 13:23

It's funny how picky the validation system is. I actually mean 'frustrating'..... Try these steps, one should pass you (hopefully): #1 at line 23 of the Solution class, use br.readline().toLowerCase() and see if that corrects the issue. #2 in the solution class, your if else blocks starting at line 32, have them test for the actual values of the Planet class, for example: thePlanet1.equals(Planet.SUN) #3 remove line 26

Guadalupe Gagnon

Level 37 , Tampa, United States

16 May 2019, 13:25

I'm at a stand still with the level i am at now. The tasks are hard and i only pass a couple a day, after multiple fails. I keep pressing on, but its like walking through mud.... uphill.

Darko Jakimovski

Level 18 , Kriva Palanka, Macedonia, The Former Yugoslav Republic of

16 May 2019, 15:25

Already tried everything. I'm sure my code does what it supposed to do. Thanks anyway. you are the bomb. Condolences on the tasks. I just asked because I'm a bit afraid of what's to come :)