Plugin Debugging HotSwap Problem

Dear all,

I am currently trying to figure out, how I can use the HotSwap functionality.

I am using Intelij Idea and followed the whole tutorial from this series:

I made a local copy of the current stable 7.1 git repository and integrated my plugin as an artifact.

I am able to debug, but when I am using the “Reload changed classes” functionality, it tries to rebuild sponge and my plugin and I receive the following error:

Unable to find source java class: ‘C:\Users\gottw.gradle\caches\minecraft\net\minecraftforge\forge\1.12.2-\start\’ because it does not belong to any of the source dirs: '[D:\SpongeForge\testmods\src\main\java]*

The strange thing is that the file at C:\Users\gottw.gradle\caches\minecraft\net\minecraftforge\forge\1.12.2-\start\ is present.

I am completely new to Intelij Idea and Sponge, but I would like to be able to use the HotSwap functionality. Does anybody of you have an idea what kind of problem I have and how I can solve it?

Has it something todo, that the project workspace is on disk D and the cache on C?

I would appreciate any help! Thanks in advance


----- Edit -----

My run configuration:

Plugin artifact:

I think I have a guess as to what’s going on. Could you send a screenshot of the “External Libraries” section in the project pane? It should look something like this:

In particular, I’m trying to see if there’s a “start” folder in that list.

1 Like

Thanks for the answer :slight_smile:

Here are my external libraries


Part 1:

Part 2:

Part 3:

Part 4:

There is a start folder refered aswell


Hm… I really have no idea what’s going on then. Are you on the latest SpongeForge and IntelliJ versions?

I updated IntelliJ IDEA and SpongeForge and now it builds the project without the described error. Now when I do some code changes in my plugin, I click on “Reloaded changed classes” and it rebuilds my plugin and SpongeFroge which causes the server to stop.

Because the console error ouput was to long I had to upload it seperatly
Copy of console output:
Crash report:

Any idea how to get HotSwap running on the latest version?


@JBYoshi or someone else, any idea left? I really want to continue developing our plugin. At the moment I have to restart the whole server for every line of code I change. It is really hard to make any progress. We migrated a Spigot plugin into Sponge with a lot of code and we need the HotSwap functionality to test and adjust the migrated code.

I would really appreciate any help …