#555: Item - add getters/setters for owner/thrower

By: Shane Bee <shanebolenback@me.com>

paper-api/src/main/java/org/bukkit/entity/Item.java

@@ -1,7 +1,9 @@
 package org.bukkit.entity;
 
+import java.util.UUID;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 /**
  * Represents a dropped item.
@@ -36,4 +38,41 @@ public interface Item extends Entity {
      * @param delay New delay
      */
     public void setPickupDelay(int delay);
+
+    /**
+     * Sets the owner of this item.
+     *
+     * Other entities will not be able to pickup this item when an owner is set.
+     *
+     * @param owner UUID of new owner
+     */
+    public void setOwner(@Nullable UUID owner);
+
+    /**
+     * Get the owner of this item.
+     *
+     * @return UUID of owner
+     */
+    @Nullable
+    public UUID getOwner();
+
+    /**
+     * Set the thrower of this item.
+     *
+     * The thrower is the entity which dropped the item. This affects the
+     * trigger criteria for item pickups, for things such as advancements.
+     *
+     * @param uuid UUID of thrower
+     */
+    public void setThrower(@Nullable UUID uuid);
+
+    /**
+     * Get the thrower of this item.
+     *
+     * The thrower is the entity which dropped the item.
+     *
+     * @return UUID of thrower
+     */
+    @Nullable
+    public UUID getThrower();
 }