1.18.1 Modding - Error with Intellij

[Lbarto12]

So I've just started to try modding minecraft, and I've done a lot of java programming before this, but I'm getting stopped by what I think are version errors. I tried setting up runClient with java 8 (following a tutorial for an older version of minecraft), but got a major.minor version error. So after some research I found that that 1.18.x uses Java 17, so I installed the JDK and switched it out in the project settings page, but now I get a new error:

Exception in thread "main" java.lang.reflect.InaccessibleObjectException: Unable to make public static void cpw.mods.bootstraplauncher.BootstrapLauncher.main(java.lang.String[]) accessible: module cpw.mods.bootstraplauncher does not "exports cpw.mods.bootstraplauncher" to unnamed module @1175e2db
    at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
    at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
    at java.base/java.lang.reflect.Method.checkCanSetAccessible(Method.java:199)
    at java.base/java.lang.reflect.Method.setAccessible(Method.java:193)
    at com.intellij.rt.execution.application.AppMainV2.main(AppMainV2.java:127)

and I've searched around but can't seem to find a thread discussing this problem (maybe I'm just blind). I'm not sure how a JDK version change would make the main function inaccessible (unless it's a completely new error that has nothing to do with version).

 

Any help / suggestions would be greatly appreciated.

 

Thanks!

[MFMods]

run genIntellijRuns task (i assume you did).

in configuration of the runClient task is a java version dropdown; pick 17. main class box in my ide (2 rows below 17) says "cpw.mods.bootstraplauncher.BootstrapLauncher" without "main". module box (to the right of 17) says main.

 

[Lbarto12]

@MFMods I appreciate you replying! unfortunately, this is the exact configuration I have. Nothing seems to work, which sucks cause I really want to learn how to mod

[MFMods]

ok, new plan - start over. unpack MDK zip into a new folder and get example mod to start. just import the build.gradle file, that'll make a new project, run genIntellijRuns (you can do it from IDE) and then runClient.

do not edit ExampleMod source or anything else until you can start it. only set java version where it's wrong.

after you can start it for the first time, you'll make edits to build.gradle, mods.toml and you'll delete a few files (txt, etc.). now it is very important that once you make those changes and confirm that they work, you turn those changes into a command line script (or a shell script). that way, for the next mod, you'll be able to initialize build.gradle and mods.toml in a second and be sure you didn't break anything.

[Lbarto12]

@MFMods I tried what you have suggested and the error is still there...   any other ideas?

[hasunemiku2015]

If you are using intellij , try installing the minecraft development kit addon and then make a new project there

It will automatically get quite a bit of stuff done for you, while it "might not be good for beginner" (said by some people in spigot forum cuz you don't learn how to configure things properly), it actually does a lot of stuff perfectly for you , so just "copy homework".

 

The addon is self-intuitive enough so I wont guide you through how to use it here

[Lbarto12]

@MFMods @hasunemiku2015 Thank you both for helping me, but I am apparently just dumb. The solution was to upgrade intellij. Since I've been writing Java code for a few years and I downloaded the IDE a long time ago.

This is how I figured it out:

I was getting very tired of the problem, so I figured I'd try Fabric and see what it was about, but when I tried to launch the game in Fabric I got a more comprehensive error telling me the gradle build wasn't compatible with my version of Intellij (which I find very strange, but such is life). With this in mind I updated and retried forge, and that was apparently all it took.

Thank you for your patience, wish me luck!