Paper/nms-patches/IInventory.patch

--- a/net/minecraft/server/IInventory.java
+++ b/net/minecraft/server/IInventory.java
@@ -1,6 +1,7 @@
 package net.minecraft.server;
 
 import javax.annotation.Nullable;
+import org.bukkit.craftbukkit.entity.CraftHumanEntity; // CraftBukkit
 
 public interface IInventory extends INamableTileEntity {
 
@@ -36,4 +37,22 @@
     int g();
 
     void l();
+
+    // CraftBukkit start
+    ItemStack[] getContents();
+
+    void onOpen(CraftHumanEntity who);
+
+    void onClose(CraftHumanEntity who);
+
+    java.util.List<org.bukkit.entity.HumanEntity> getViewers();
+
+    org.bukkit.inventory.InventoryHolder getOwner();
+
+    void setMaxStackSize(int size);
+
+    org.bukkit.Location getLocation();
+
+    int MAX_STACK = 64;
+    // CraftBukkit end
 }