How to correctly write paths to resources in Java?

Question

Java

Good day to all. I am currently learning java. I develop in intellij idea.
Undertook to implement a simple reference using javafx. The sqlite database, maven pulls up the necessary libraries to connect. Everything works while you run from idea and stops working after building in jar. In the process of studying, I realized that I was collecting it in the wrong way and with the paths I have a complete mess.
Therefore, the question is how to correctly register the paths to the resources folder?
In idea, when you create a maven project, we have the following structure

src
--main
----java
------Main
----resources
------db
--------test.db
------test.fxml
--test
pom.xml

How to correctly set the path to test.fxml and test.db in Main?
At the moment fxml (moved it to the root to Main) I get through

Parent root = FXMLLoader.load(getClass().getResource("main.fxml"));

But that's not right for me

Answer 1

Why when calling
from Main
In the terminal gives
file:/E:/JavaProjects/test/target/classes/test.db