JavaFX Application not loading fxml files when exported to a jar file - javafx

Question

I have just finished my first java project, however I can't seem to get it to build properly. It will load the initial fxml file that the whole calculator runs on, however when I try to add a holiday/break in the holiday/break menu a dialogpane is supposed to display so the user can fill information, but I keep getting a location not set error when I run the jar file in the cmd. It all works when I launch it in intellij but not in the jar.
This is how I have my files set up. I made a resource directory in the FinishedCalCulator project and marked it as the resource root
This is how I set the Location of the FXML file into the loader. This works when I run it in Intellij but not in the jar file.
Project Structure
Running through CMD
Invocation Target Exception/Location not set error
I have looked around and found a few posts talking about putting all of the fxml files into a resource file and I did that and got it working again in Intellij, but it still will not display the dialog panes when I try to add them. I'm not really sure what I am doing wrong here. I don't think I fully understand what I am doing wrong. Any help would be great.

Answer 1

To expand on my comment...
Answer
In your code you are calling getResource("/addHolidayDialog.fxml"). Your resource's filename, however, is AddHolidayDialog.fxml. Simply change the "a" in your code to "A" and your code should work.
Explanation
Running from Intellij
When you run your application from Intellij it uses the output files in the out/production/classes directory. In other words, the classes are not in a JAR file. When you call getClass().getResource("/addHolidayDialog.fxml") you will get a URL like:
file://C:/.../out/production/classes/addHolidayDialog.fxml
Which works on Windows despite the fact the file is actually named AddHolidayDialog.fxml because Windows has a case-insensitive file system.
Running from JAR
Then you export your project to a JAR and run it from there. Calling the same getResource code you will now get a URL (if the code worked) like:
jar:file://C:/.../your-application.jar!/addHolidayDialog.fxml
What your code actually returns from getResource, however, is null. According to the JAR file, the resource addHoldiayDialog.fxml doesn't exist. It'll happily tell you that AddHolidayDialog.fxml does exist, however. The reason for this being that a JAR file has a case-sensitive "file system".