Many javadoc fixes thanks to Celtic Minstrel

By: Dinnerbone <dinnerbone@dinnerbone.com>

paper-api/src/main/java/org/bukkit/inventory/FurnaceRecipe.java

@@ -60,7 +60,7 @@ public class FurnaceRecipe implements Recipe {
      * @return The input material.
      */
     public MaterialData getInput() {
-        return (MaterialData) ingredient;
+        return ingredient;
     }
 
     /**

paper-api/src/main/java/org/bukkit/inventory/Inventory.java

@@ -45,7 +45,7 @@ public interface Inventory {
      * It will return a HashMap of what it couldn't fit.
      *
      * @param items The ItemStacks to add
-     * @return
+     * @return The items that didn't fit.
      */
     public HashMap<Integer, ItemStack> addItem(ItemStack... items);
 
@@ -56,7 +56,7 @@ public interface Inventory {
      * give as arguments. It will return a HashMap of what it couldn't remove.
      *
      * @param items The ItemStacks to remove
-     * @return
+     * @return The items that couldn't be removed.
      */
     public HashMap<Integer, ItemStack> removeItem(ItemStack... items);
 
@@ -70,7 +70,7 @@ public interface Inventory {
     /**
      * Set the inventory's contents
      *
-     * @return All the ItemStacks from all slots
+     * @param items A complete replacement for the contents; the length must be equal to {@link #getSize()}.
      */
     public void setContents(ItemStack[] items);
 
@@ -112,6 +112,7 @@ public interface Inventory {
      * Check if the inventory contains any ItemStacks with the given material and at least the minimum amount specified
      *
      * @param material The material to check for
+     * @param amount The minimum amount
      * @return If any ItemStacks were found
      */
     public boolean contains(Material material, int amount);
@@ -121,6 +122,7 @@ public interface Inventory {
      * This will only match if both the type and the amount of the stack match
      *
      * @param item The ItemStack to match against
+     * @param amount The minimum amount
      * @return If any matching ItemStacks were found
      */
     public boolean contains(ItemStack item, int amount);
@@ -136,7 +138,7 @@ public interface Inventory {
     /**
      * Find all slots in the inventory containing any ItemStacks with the given material
      *
-     * @param materialId The material to look for
+     * @param material The material to look for
      * @return The Slots found.
      */
     public HashMap<Integer, ? extends ItemStack> all(Material material);
@@ -161,7 +163,7 @@ public interface Inventory {
     /**
      * Find the first slot in the inventory containing an ItemStack with the given material
      *
-     * @param materialId The material to look for
+     * @param material The material to look for
      * @return The Slot found.
      */
     public int first(Material material);

paper-api/src/main/java/org/bukkit/inventory/ItemStack.java

@@ -125,7 +125,7 @@ public class ItemStack {
     /**
      * Sets the MaterialData for this stack of items
      *
-     * @param amount New MaterialData for this item
+     * @param data New MaterialData for this item
      */
     public void setData(MaterialData data) {
         Material mat = getType();