@Mod("xy")
@Mod.EventBusSubscriber(bus = Mod.EventBusSubscriber.Bus.MOD)
public class XYMod() {
	// ...
	@SubscribeEvent
	public static void onEntityRegistry(final RegistryEvent.Register<EntityType<?>> event) {
		IForgeRegistry<EntityType<?>> r = event.getRegistry();
		r.register(EntityType.Builder.create(EntityItemNoDespawn::new, EntityClassification.MISC)
	              .size(0.25f, 0.25f)
	              .setShouldReceiveVelocityUpdates(false)
	              .build("item_nodespawn").setRegistryName("xy", "item_nodespawn"));
	}
}

Above is my main mod class, where I register the entity. It extends the vanilla ItemEntity. My custom item class:

public class ItemXY extends Item {
    // ...

    public boolean hasCustomEntity(ItemStack stack) {
        return true;
    }

    public Entity createEntity(World world, Entity location, ItemStack itemstack) {
        return new EntityItemNoDespawn(world, location.posX, location.posY, location.posZ, itemstack);
    }
}

When I try to load a world that already contains an EntityItemNoDespawn (created by dropping my item), it gets stuck at the square loading screen (at 100%). These are the last lines of the log:

[08:54:45] [Server thread/INFO] [minecraft/SimpleReloadableResourceManager]: Reloading ResourceManager: Default, forge-1.14.4-28.1.79_mapped_snapshot_20190719-1.14.3-recomp.jar, main
[08:54:46] [Server thread/INFO] [minecraft/RecipeManager]: Loaded 6 recipes
[08:54:47] [Server thread/INFO] [minecraft/AdvancementList]: Loaded 811 advancements
[08:54:47] [Server thread/INFO] [minecraft/MinecraftServer]: Preparing start region for dimension minecraft:overworld
[08:54:47] [Client thread/INFO] [minecraft/LoggingChunkStatusListener]: Preparing spawn area: 0%
[08:54:47] [Client thread/INFO] [minecraft/LoggingChunkStatusListener]: Preparing spawn area: 0%
[08:54:48] [Client thread/INFO] [minecraft/LoggingChunkStatusListener]: Preparing spawn area: 46%

 

1. Please post more of your code, especially the code of EntityItemNoDespawn.

2. "xy" is not a good mod id as it is too short and will cause conflict. Consider using a longer and more unique name.

EntityItemNoDespawn:

public class EntityItemNoDespawn extends ItemEntity {
    public EntityItemNoDespawn(EntityType<?> type, World world) {
        super((EntityType<? extends ItemEntity>) type, world);
        this.setNoDespawn();
    }
    public EntityItemNoDespawn(World world, double x, double y, double z, ItemStack stack) {
        super(world, x, y, z, stack);
        this.setNoDespawn();
    }
}

 

12 hours ago, Wurst said:

These are the last lines of the log:

We need to see the whole log. Also what DavidM said about your mod I'd. It's not something you should consider. It's really just an action you need to take. 

Here's the whole debug.log file: https://paste.ee/p/3dWdC

16 minutes ago, Wurst said:

Here's the whole debug.log file: https://paste.ee/p/3dWdC

Nothing that stands out completely there would you mind posting the entirety of your EntityItemNoDespawn and Your Register<EntityType> event method.

The Register<EntityType> event method is in my main mod class, which I posted in my first comment. The issue already appears with the reduced class I posted. This is the full class:

public class EntityItemNoDespawn extends ItemEntity {
    public EntityItemNoDespawn(EntityType<?> type, World world) {
        super((EntityType<? extends ItemEntity>) type, world);
        this.rotationYaw = (float)(Math.random() * 360.0D);
        this.setMotion(0, -1, 0);
        this.setInfinitePickupDelay();
        this.setNoDespawn();
    }
    public EntityItemNoDespawn(World world, double x, double y, double z, ItemStack stack) {
        super(world, x, y, z, stack);
        this.setPosition(Math.round(x) + 0.5, Math.round(y) + 0.5, Math.round(z) + 0.5);
        this.rotationYaw = (float)(Math.random() * 360.0D);
        this.setMotion(0, -1, 0);
        this.setInfinitePickupDelay();
        this.setNoDespawn();
    }

    @Override
    public void tick() {
        this.setCustomName(new StringTextComponent(this.getItem().getCount() + " " + this.getItem().getDisplayName()));
        this.setCustomNameVisible(true);
        super.tick();
    }

    @Override
    public boolean getAlwaysRenderNameTagForRender() {
        return true;
    }
}