I have a little problem.

When I runData, I get this error.

Caused by: java.lang.NullPointerException: Cannot invoke "net.minecraft.world.item.CreativeModeTab.getRecipeFolderName()" because the return value of "net.minecraft.world.item.Item.getItemCategory()" is null

These are my recipes:

ShapedRecipeBuilder.shaped(ModBlocks.FLINT_BLOCK.get()).define('#', Items.FLINT).pattern("###").pattern("###").pattern("###").unlockedBy("has_material", has(Items.FLINT)).save(pFinishedRecipeConsumer);
ShapedRecipeBuilder.shaped(ModBlocks.CHARCOAL_BLOCK.get()).define('#', Items.CHARCOAL).pattern("###").pattern("###").pattern("###").unlockedBy("has_material", has(Items.CHARCOAL)).save(pFinishedRecipeConsumer);

How can I fix this?

 

Here is my creative mode tab declaration.

    public static final CreativeModeTab TAB_BETTER_MATERIALS = new CreativeModeTab("better_materials") {
        @Override public @NotNull ItemStack makeIcon() {return new ItemStack(ModBlockItems.FLINT_BLOCK.get());}
    };

Here are my BlockItems, which have a creative mode tab set.

    public static final RegistryObject<Item> FLINT_BLOCK = BLOCK_ITEMS.register("flint_block", ()-> new BlockItem(ModBlocks.FLINT_BLOCK.get(), new Item.Properties().tab(BetterMaterials.TAB_BETTER_MATERIALS)));
    public static final RegistryObject<Item> CHARCOAL_BLOCK = BLOCK_ITEMS.register("charcoal_block", ()-> new BlockItem(ModBlocks.FLINT_BLOCK.get(), new Item.Properties().tab(BetterMaterials.TAB_BETTER_MATERIALS)) {
        @Override public int getBurnTime(ItemStack itemStack, @Nullable RecipeType<?> recipeType) {return 16000;}
    });

The recipe is for a Block, and the block doesn't have a creative mode tab, the blockitem has. Could it be an error from the anonymous class, even tho the error is thrown twice for both blocks...

Edited March 7, 20223 yr by Darkorg69

Spoiler

Exception in thread "main" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
	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:149)
Caused by: java.lang.reflect.InvocationTargetException
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at MC-BOOTSTRAP/[email protected]/net.minecraftforge.fml.loading.targets.ForgeDataUserdevLaunchHandler.lambda$launchService$0(ForgeDataUserdevLaunchHandler.java:41)
	at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.LaunchServiceHandlerDecorator.launch(LaunchServiceHandlerDecorator.java:37)
	... 7 more
Caused by: java.lang.NullPointerException: Cannot invoke "net.minecraft.world.item.CreativeModeTab.getRecipeFolderName()" because the return value of "net.minecraft.world.item.Item.getItemCategory()" is null
	at TRANSFORMER/[email protected]/net.minecraft.data.recipes.ShapedRecipeBuilder.save(ShapedRecipeBuilder.java:94)
	at TRANSFORMER/[email protected]/net.minecraft.data.recipes.RecipeBuilder.save(RecipeBuilder.java:21)
	at TRANSFORMER/[email protected]/darkorg.bettermaterials.data.common.ModRecipeProvider.buildCraftingRecipes(ModRecipeProvider.java:31)
	at TRANSFORMER/[email protected]/net.minecraft.data.recipes.RecipeProvider.run(RecipeProvider.java:97)
	at TRANSFORMER/[email protected]/net.minecraft.data.DataGenerator.run(DataGenerator.java:44)
	at TRANSFORMER/[email protected]/net.minecraftforge.forge.event.lifecycle.GatherDataEvent$DataGeneratorConfig.lambda$runAll$0(GatherDataEvent.java:98)
	at MC-BOOTSTRAP/[email protected]/cpw.mods.modlauncher.api.LamdbaExceptionUtils.lambda$rethrowConsumer$0(LamdbaExceptionUtils.java:34)
	at java.base/java.util.HashMap$Values.forEach(HashMap.java:1065)
	at TRANSFORMER/[email protected]/net.minecraftforge.forge.event.lifecycle.GatherDataEvent$DataGeneratorConfig.runAll(GatherDataEvent.java:94)
	at TRANSFORMER/[email protected]/net.minecraftforge.data.loading.DatagenModLoader.begin(DatagenModLoader.java:45)
	at TRANSFORMER/[email protected]/net.minecraft.data.Main.main(Main.java:67)
	... 13 more
Caused by: java.lang.reflect.InvocationTargetException

Caused by: java.lang.NullPointerException: Cannot invoke "net.minecraft.world.item.CreativeModeTab.getRecipeFolderName()" because the return value of "net.minecraft.world.item.Item.getItemCategory()" is null


> Task :runData FAILED

Execution failed for task ':runData'.
> Process 'command 'C:\Program Files\Java\jdk-17.0.2\bin\java.exe'' finished with non-zero exit value 1

 

Here is the log.

The issue was related to a typo in my BlockItem declaration.