Add CompostItemEvent and EntityCompostItemEvent

paper-api/src/main/java/io/papermc/paper/event/block/CompostItemEvent.java

@@ -0,0 +1,66 @@
+package io.papermc.paper.event.block;
+
+import org.bukkit.block.Block;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.block.BlockEvent;
+import org.bukkit.event.inventory.InventoryMoveItemEvent;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Called when an item is about to be composted by a hopper.
+ * To prevent hoppers from moving items into composters, cancel the {@link InventoryMoveItemEvent}.
+ */
+@NullMarked
+public class CompostItemEvent extends BlockEvent {
+
+    private static final HandlerList HANDLER_LIST = new HandlerList();
+
+    private final ItemStack item;
+    private boolean willRaiseLevel;
+
+    @ApiStatus.Internal
+    public CompostItemEvent(final Block composter, final ItemStack item, final boolean willRaiseLevel) {
+        super(composter);
+        this.item = item;
+        this.willRaiseLevel = willRaiseLevel;
+    }
+
+    /**
+     * Gets the item that was used on the composter.
+     *
+     * @return the item
+     */
+    public ItemStack getItem() {
+        return this.item;
+    }
+
+    /**
+     * Gets whether the composter will rise a level.
+     *
+     * @return {@code true} if successful
+     */
+    public boolean willRaiseLevel() {
+        return this.willRaiseLevel;
+    }
+
+    /**
+     * Sets whether the composter will rise a level.
+     *
+     * @param willRaiseLevel {@code true} if the composter should rise a level
+     */
+    public void setWillRaiseLevel(final boolean willRaiseLevel) {
+        this.willRaiseLevel = willRaiseLevel;
+    }
+
+    @Override
+    public HandlerList getHandlers() {
+        return HANDLER_LIST;
+    }
+
+    public static HandlerList getHandlerList() {
+        return HANDLER_LIST;
+    }
+
+}

paper-api/src/main/java/io/papermc/paper/event/entity/EntityCompostItemEvent.java

@@ -0,0 +1,45 @@
+package io.papermc.paper.event.entity;
+
+import io.papermc.paper.event.block.CompostItemEvent;
+import org.bukkit.block.Block;
+import org.bukkit.entity.Entity;
+import org.bukkit.event.Cancellable;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Called when an item is about to be composted by an entity.
+ */
+@NullMarked
+public class EntityCompostItemEvent extends CompostItemEvent implements Cancellable {
+
+    private final Entity entity;
+    private boolean cancelled;
+
+    @ApiStatus.Internal
+    public EntityCompostItemEvent(final Entity entity, final Block composter, final ItemStack item, final boolean willRaiseLevel) {
+        super(composter, item, willRaiseLevel);
+        this.entity = entity;
+    }
+
+    /**
+     * Gets the entity that interacted with the composter.
+     *
+     * @return the entity that composted an item.
+     */
+    public Entity getEntity() {
+        return this.entity;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void setCancelled(final boolean cancel) {
+        this.cancelled = cancel;
+    }
+
+}