I'm trying to upgrade my 1.16 mod to 1.17, and after updating my code, I get this error.

 

Exception in thread "main" java.lang.RuntimeException: java.lang.StringIndexOutOfBoundsException: begin 0, end -1, length 3
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:39)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:53)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.LaunchServiceHandler.launch(LaunchServiceHandler.java:71)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.Launcher.run(Launcher.java:106)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.Launcher.main(Launcher.java:77)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:26)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.BootstrapLaunchConsumer.accept(BootstrapLaunchConsumer.java:23)
        at [email protected]/cpw.mods.bootstraplauncher.BootstrapLauncher.main(BootstrapLauncher.java:89)
Caused by: java.lang.StringIndexOutOfBoundsException: begin 0, end -1, length 3
        at java.base/java.lang.String.checkBoundsBeginEnd(String.java:3751)
        at java.base/java.lang.String.substring(String.java:1907)
        at [email protected]/cpw.mods.cl.ModuleClassLoader.loadClass(ModuleClassLoader.java:128)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
        at java.base/java.lang.Class.getDeclaredMethods0(Native Method)
        at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3334)
        at java.base/java.lang.Class.getMethodsRecursive(Class.java:3475)
        at java.base/java.lang.Class.getMethod0(Class.java:3461)
        at java.base/java.lang.Class.getMethod(Class.java:2193)
        at MC-BOOTSTRAP/[email protected]/net.minecraftforge.fml.loading.targets.ForgeClientUserdevLaunchHandler.lambda$launchService$0(ForgeClientUserdevLaunchHandler.java:38)
        at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37)
        ... 7 more

 

I can't for the life of me, figure out why it is giving me this error.

I also got the exact same error running the 1.17 mdk

did you run the gradle refresh task, for your ide and trhe dependencies?

I was actually able to figure it out with the help of some people on a discord server! Thanks for trying to help though.

11 minutes ago, Pinary said:

I was actually able to figure it out with the help of some people on a discord server! Thanks for trying to help though.

what was the solution (for people who have the same problem)?

The solution was to delete client:extra jar from ~/.gradle/caches/forge_gradle/minecraft_repo/versions/1.17.1