Kotlin/IntelliJ Modules with Shared Content Root - intellij-idea

Question

I'm working on a project in IntelliJ Idea using Kotlin. I'm trying to create a unit test for a Kotlin class, and I can create the class, except that when I run the test, I get an error that there is no JDK configured. I go into the project structure and change the JDK for the module, but when I click on Apply, I get a message saying that :
Content root
"C:\Users\2rtmar\Documents\xproject\xproject\examples\src\main" is
defined for modules "xproject-examples-utils_main" and
"xproject-examples-java_main". Two modules in a project cannot share
the same content root.
Another team member had said that these modules were faulty, and that they couldn't be used, but I'm not using them and still prevent me from running my code. I tried to unmark this module as a sources root, but did not fix the problem. I went as far as to removing the xproject\examples module entirely, but received the same message when trying to set the JDK of my module.
Any help is appreciated!

Answer 1

In my case I was trying to setup a multi-module Gradle project by adding a new module to my root Gradle project.
Despite adding an include ':my-submodule' to my settings.gradle, it
was always telling me gradle wrapper not found, because the submodule was kind of outside of the context of the root module.
This however is IntelliJ-specific
When I looked into Right-Click on module -> Open Module Settings - > Modules I was seeing the following hierarchy:
my-root
-> my-submodule
my-submodule
For whatever reason, IntelliJ has added the new module as a child and as a standalone module, and this caused the issue Two modules cannot have the same content root, as my-root:my-submodule and my-submodule are now both pointing to the same src/main directory.
This is IntelliJ's out of the box behaviour when adding a new
submodule, which is in my opinion totally wrong and likely a bug! You
cannot even fix it within the module settings
Solution
But I discovered a way to fix it.
Right-click on the module
Load/Unload Modules
Now unload the module that is not below the my-root
After that, there is just one single root pointing at the src directory and the active module is now within the parent's Gradle scope.
I hope Jetbrains fixes these issues. Those problems exist for a while now and are not pleasant to solve.

Answer 2

I got this issue recently.
The very first check should be to check if any other module with the same content root is added or not.[you can check this in Project Structure -> Modules]
If YES, remove the other project by clicking on - (minus) button at the top.

Answer 3

If you're using Intellij and have modified / are modifying the pom.xml files directly:
Go to the affected sources' pom.xml files
Go to the following area:
...
<build>
...
<resources>
<resource>
...
<directory>[DIRECTORY]</directory>
...
<includes>
...
</includes>
...
</resource>
</resources>
...
</build>
...
Change the [DIRECTORY] to something unique. For instance, I was referencing ../plugin-outputs. As such, I changed it to ../plugin-outputs/[specific sub-directory], wherein I named the sub directory as I wished.
Delete any "modules" listing the specific output directory. No, they aren't modules... however, they have the module icon applied to this, preventing the pom.xml files' changes to be updated while editing modules through the standard project structure tab.
I know this thread is 2 years old; however, there are MANY people who still read these artifacts... hopefully this helps someone.
-Dan