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Bug Report: NoSuchMethodError crash on Forge 1.20.1 (47.4.20) #48

@ElGato-ConBotas

Description

@ElGato-ConBotas

Description
RoadArchitect fails to initialize on Forge 1.20.1 (47.4.20), crashing the game during the mod construction phase before the main menu loads.

Error

[14:55:30] [modloading-worker-0/ERROR]: Failed to create mod instance. ModID: roadarchitect, class net.oxcodsnet.roadarchitect.forge.RoadArchitectForge
java.lang.NoSuchMethodError: 'net.minecraft.resources.ResourceLocation net.minecraft.resources.ResourceLocation.tryParse(java.lang.String)'
	at net.oxcodsnet.roadarchitect.handlers.RoadPipelineController.cacheStructureSelectors(RoadPipelineController.java:153)
	at net.oxcodsnet.roadarchitect.handlers.RoadPipelineController.refreshStructureSelectorCache(RoadPipelineController.java:69)
	at net.oxcodsnet.roadarchitect.forge.config.RAConfigForgeBridge.bootstrap(RAConfigForgeBridge.java:280)
	at net.oxcodsnet.roadarchitect.forge.RoadArchitectForge.<init>(RoadArchitectForge.java:27)

Cause
ResourceLocation.tryParse(String) is not available under that name in Forge 1.20.1's mappings. The method exists in 1.20.1, but the mod appears to be compiled against a newer API (1.21.x style), where the method was later renamed/restructured.

Environment

  • Mod version: roadarchitect-1.6.6-forge+1.20.1.jar
  • Forge version: 47.4.20
  • Minecraft version: 1.20.1
  • Java: 17.0.8 (Eclipse Adoptium)
  • OS: Windows 11 x64

Steps to reproduce

  1. Install Forge 1.20.1-47.4.20
  2. Add roadarchitect-1.6.6-forge+1.20.1.jar to the mods folder
  3. Launch the game
  4. Game crashes during mod loading

Expected behavior
Mod loads and initializes correctly.

Additional notes
This appears to affect all versions of RoadArchitect for Forge 1.20.1, not just 1.6.6, since the issue is in RoadPipelineController.java which is core logic present across versions. The 1.20.1 Forge port was introduced in v1.6.1 (October 2025) and may have been compiled against 1.21.x mappings without fully adapting the API.

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