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====== Loot Table Generation ======

In this tutorial, you will learn how to generate loot tables for blocks and other contents. With data generation, you do not need to write JSONs for each block anymore. Before reading this, make sure you've read [[datagen_setup|Getting started with Data Generation]], and have a class that implements ''DataGenerationEntrypoint''.

===== Block loot tables =====
To create add a data generation for block loot tables, just create a class which extends ''FabricBlockLootTableProvider''.

<code java TutorialBlockLootTableProvider.java>
public class TutorialBlockLootTableProvider extends FabricBlockLootTableProvider {
  protected TutorialBlockLootTableProvider(FabricDataOutput dataOutput, CompletableFuture<RegistryWrapper.WrapperLookup> registryLookup) {
    super(dataOutput, registryLookup);
  }

  @Override
  public void generate() {
    // ...
  }
}
</code>

And then, add this data generation in the entrypoint (we use ''ExampleModDataGenerator'' as an example):
<code java ExampleModDataGenerator.java>
public class ExampleModDataGenerator implements DataGeneratorEntrypoint {
  @Override
  public void onInitializeDataGenerator(FabricDataGenerator generator) {
    FabricDataGenerator.Pack pack = generator.createPack();

    pack.addProvider(TutorialBlockLootTableProvider::new);
  }
}
</code>

> If you're using versions pre-1.20, please replace ''pack.addProvider(TutorialBlockLootTableProvider::new);'' with ''fabricDataGenerator.addProvider(TutorialBlockLootTableProvider::new);'' and remove ''FabricDataGenerator.Pack myPack = fabricDataGenerator.createPack();''。

In the previous [[blocks]] tutorial, we created an //example block//. Now let's use the data generator to generate its loot table. It's as simple as:
<code java TutorialBlockLootTableProvider>
  @Override
  public void generate() {
    addDrop(TutorialBlocks.EXAMPLE_BLOCK);
  }
</code>

This is the most common loot table for a block. When mined, drops one. When exploded in a explosion with decay (such as creeper and nether bed), it may be destroyed totally and drop nothing.

You can also make it drop a little more complex, for example (the code is just to show an exmaple; please do not add loot tables for one block multiple times):
<code java>
    // drops nothing
    addDrop(TutorialBlocks.EXAMPLE_BLOCK, dropsNothing());
    
    // drops a dirt when mined
    addDrop(TutorialBlocks.EXAMPLE_BLOCK, Blocks.DIRT);
    
    // drops itself only when with tools with Silk Touch, otherwise drops nothing
    addDropWithSilkTouch(TutorialBlocks.EXAMPLE_BLOCK);
    
    // drops itself only when with tools with Silk Touch, otherwise drops a dirt block
    addDropWithSilkTouch(TutorialBlocks.EXAMPLE_BLOCK, Blocks.DIRT);
    
    // drops itself only when with shears or tools with Silk Touch, otherwise drops nothing
    addDrop(TutorialBlocks.EXAMPLE_BLOCK, dropsWithSilkTouchOrShears(TutorialBlocks.EXAMPLE_BLOCK));
    
    // drops three blocks
    addDrop(TutorialBlocks.EXAMPLE_BLOCK, drops(TutorialBlocks.EXAMPLE_BLOCK)
        .apply(SetCountLootFunction.builder(ConstantLootNumberProvider.create(5))));
</code>

You can also generate data for the [[crops]] we introduced before:
<code java>
    addDrop(TutorialBlocks.CUSTOM_CROP, cropDrops(TutorialBlocks.CUSTOM_CROP, TutorialItems.CUSTOM_ITEM, TutorialItems.CUSTOM_SEEDS, BlockStatePropertyLootCondition.builder(TutorialBlocks.CUSTOM_CROP).properties(StatePredicate.Builder.create().exactMatch(CropBlock.AGE, 7))));
</code>

===== Simple Loot Table =====

To add a simple loot table, which can also be used in many occasions, such as chests, we just extend ''SimpleFabricLootTableProvider''.
<code java TutorialChestLootTableProvider.java>
public class TutorialChestLootTableProvider extends SimpleFabricLootTableProvider {
  public TutorialChestLootTableProvider(FabricDataOutput output, CompletableFuture<RegistryWrapper.WrapperLookup> registryLookup) {
    super(output, registryLookup, LootContextTypes.CHEST);
  }

  public static final RegistryKey<LootTable> TEST_CHEST = RegistryKey.of(RegistryKeys.LOOT_TABLE, Identifier.of("tutorial", "test_chest"));

  @Override
  public void accept(BiConsumer<RegistryKey<LootTable>, LootTable.Builder> lootTableBiConsumer) {
    lootTableBiConsumer.accept(TEST_CHEST, LootTable.builder()
        .pool(LootPool.builder().rolls(ConstantLootNumberProvider.create(1.0F))
            .with(ItemEntry.builder(Items.DIAMOND)
                .apply(SetCountLootFunction.builder(ConstantLootNumberProvider.create(1.0F))))
            .with(ItemEntry.builder(Items.DIAMOND_SWORD)))
    );
  }
}
</code>

And then in your entry point:
<code java ExampleModDataGenerator.java>
public class ExampleModDataGenerator implements DataGeneratorEntrypoint {
  @Override
  public void onInitializeDataGenerator(FabricDataGenerator generator) {
    // ...

    pack.addProvider(TutorialChestLootTableProvider::new);
  }
}
</code>

If you're using versions pre-1.20, please replace ''pack.addProvider(TutorialChestLootTableProvider::new);'' with ''fabricDataGenerator.addProvider(TutorialChestLootTableProvider::new);'', and remove ''FabricDataGenerator.Pack myPack = fabricDataGenerator.createPack();''.

Now run the data generator, then start Minecraft and run the command ''/loot give @s loot tutorial:test_chest'' multiple times. See what happens!