Better NullPointerHandling

Also sort-of fixed a spigot-exclusive bug with item merging, however it still doesn't work for whatever reason and actually "fixing" this bug would require some hacky workarounds, one (registering a new enchantment) basically destroys a selling point that we currently have (that we don't register any enchantments and as such don't make use of high amounts of reflection (we still make use of some reflection, but it's not as extreme)).

Signed-off-by: Geolykt <[email protected]>

pom.xml

@@ -34,6 +34,14 @@
             <artifactId>spigot-api</artifactId>
             <version>1.16.4-R0.1-SNAPSHOT</version>
             <scope>provided</scope>
+            <type>jar</type>
+        </dependency>
+        <dependency>
+            <groupId>org.spigotmc</groupId>
+            <artifactId>spigot-api</artifactId>
+            <version>1.16.4-R0.1-SNAPSHOT</version>
+            <scope>provided</scope>
+            <type>javadoc</type>
         </dependency>
         <!-- https://mvnrepository.com/artifact/org.jetbrains/annotations -->
         <dependency>

src/main/java/de/geolykt/enchantments_plus/compatibility/CompatibilityAdapter.java

@@ -93,10 +93,10 @@ public CompatibilityAdapter(Plugin plugin) {
     private EnumSet<Material> getMaterialSet(FileConfiguration config, String path) {
         EnumSet<Material> es = EnumSet.noneOf(Material.class);
         for (String materialName : config.getStringList(path)) {
-        	Material material = Material.matchMaterial(materialName);
-        	if (material != null) {
+             Material material = Material.matchMaterial(materialName);
+             if (material != null) {
                 es.add(material);
-        	}
+             }
         }
         return es;
     }

src/main/java/de/geolykt/enchantments_plus/compatibility/enchantmentgetters/AdvancedLoreGetter.java

@@ -7,6 +7,7 @@
 import org.bukkit.Material;
 import org.bukkit.World;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.Nullable;
 
 import de.geolykt.enchantments_plus.CustomEnchantment;
 
@@ -36,7 +37,7 @@ public AdvancedLoreGetter(EnumSet<Material> allowlist, boolean denylistToggle) {
     }
 
     @Override
-    public LinkedHashMap<CustomEnchantment, Integer> getEnchants(ItemStack stk, boolean acceptBooks, World world,
+    public LinkedHashMap<CustomEnchantment, Integer> getEnchants(@Nullable ItemStack stk, boolean acceptBooks, World world,
             List<String> outExtraLore) {
         if (stk != null) {
             if (isGetterDenylist) {

src/main/java/de/geolykt/enchantments_plus/compatibility/enchantmentgetters/BasicLoreGetter.java

@@ -15,6 +15,7 @@
 import org.bukkit.World;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.ItemMeta;
+import org.jetbrains.annotations.Nullable;
 
 import de.geolykt.enchantments_plus.Config;
 import de.geolykt.enchantments_plus.CustomEnchantment;
@@ -28,30 +29,29 @@
 public class BasicLoreGetter implements IEnchGatherer {
 
     @Override
-    public LinkedHashMap<CustomEnchantment, Integer> getEnchants(ItemStack stk, boolean acceptBooks, World world,
+    public LinkedHashMap<CustomEnchantment, Integer> getEnchants(@Nullable ItemStack stk, boolean acceptBooks, World world,
             List<String> outExtraLore) {
         LinkedHashMap<CustomEnchantment, Integer> map = new LinkedHashMap<>();
         if (stk != null && (acceptBooks || stk.getType() != Material.ENCHANTED_BOOK)) {
-            if (stk.hasItemMeta()) {
-                if (stk.getItemMeta().hasLore()) {
-                    Config cfg = Config.get(world);
-                    List<String> lore = stk.getItemMeta().getLore();
-                    for (String raw : lore) {
-                        Map.Entry<CustomEnchantment, Integer> ench = getEnchant(raw, cfg);
-                        if (ench != null) {
-                            map.put(ench.getKey(), ench.getValue());
-                        } else {
-                            if (outExtraLore != null) {
-                                outExtraLore.add(raw);
-                            }
+            if (stk.getItemMeta() != null && stk.getItemMeta().hasLore() && stk.getItemMeta().getLore() != null) {
+                Config cfg = Config.get(world);
+                List<String> lore = stk.getItemMeta().getLore();
+                for (String raw : lore) {
+                    Map.Entry<CustomEnchantment, Integer> ench = getEnchant(raw, cfg);
+                    if (ench != null) {
+                        map.put(ench.getKey(), ench.getValue());
+                    } else {
+                        if (outExtraLore != null) {
+                            outExtraLore.add(raw);
                         }
                     }
                 }
             }
         }
         return map;
     }
-
+
+    @Nullable
     private Map.Entry<CustomEnchantment, Integer> getEnchant(String raw, Config cfg) {
         raw = raw.replaceAll("(" + ChatColor.COLOR_CHAR + ".)", "").trim();
         switch (raw.split(" ").length) {
@@ -135,7 +135,7 @@ public void setEnchantment(ItemStack stk, CustomEnchantment ench, int level, Wor
 
     @Override
     public int getEnchantmentLevel(Config config, ItemStack stk, BaseEnchantments enchantment) {
-        if (stk != null && stk.hasItemMeta() && stk.getItemMeta().hasLore()) {
+        if (stk != null && stk.hasItemMeta() && stk.getItemMeta().getLore() != null) {
             for (String raw : stk.getItemMeta().getLore()) {
                 Map.Entry<CustomEnchantment, Integer> ench = getEnchant(raw, config);
                 if (ench != null && ench.getKey().asEnum() == enchantment) {

src/main/java/de/geolykt/enchantments_plus/compatibility/enchantmentgetters/IEnchGatherer.java

@@ -74,7 +74,7 @@ public abstract LinkedHashMap<CustomEnchantment, Integer> getEnchants(@Nullable
 
     /**
      * Checks whether an Item has a given Enchantment. This should be used instead of a normal map.contains() as it can be
-     * Optimized by some getters to result in significantly better performance.
+     * Optimised by some getters to result in significantly better performance.
      * @param config The configuration that should be used
      * @param stk The stack that should be read
      * @param ench The Enchantment that should be searched for.
@@ -87,7 +87,7 @@ public default boolean hasEnchantment(Config config, ItemStack stk, BaseEnchantm
 
     /**
      * Returns the level of a given enchantment. This should be used instead of a normal map.get() as it can be
-     * Optimized by some getters to result in significantly better performance. <br>
+     * Optimised by some getters to result in significantly better performance. <br>
      * In case the enchantment is not found, 0 should be returned.
      * @param config The configuration that should be used
      * @param stk The stack that should be read

src/main/java/de/geolykt/enchantments_plus/compatibility/enchantmentgetters/LeightweightPDCGetter.java

@@ -32,14 +32,17 @@ public LinkedHashMap<CustomEnchantment, Integer> getEnchants(ItemStack stk, bool
             List<String> outExtraLore) {
         LinkedHashMap<CustomEnchantment, Integer> map = new LinkedHashMap<>();
         if ( (stk != null && stk.getType() != Material.AIR) && (acceptBooks || stk.getType() != Material.ENCHANTED_BOOK)) {
-            if (stk.hasItemMeta()) {
+            if (stk.getItemMeta() != null) {
 
                 final PersistentDataContainer cont = stk.getItemMeta().getPersistentDataContainer();
 
                 Set<NamespacedKey> keys = cont.getKeys();
+                if (keys == null) {
+                    return map;
+                }
 
                 for (NamespacedKey key : keys) {
-                    if (!key.getNamespace().toLowerCase(Locale.ROOT).equals("enchantments_plus")) {
+                    if (!key.getNamespace().toLowerCase(Locale.ROOT).equals("enchantments_plus")) { // FIXME hardcoded string!
                         continue;
                     }
                     if (!key.getKey().split("\\.")[0].equals("ench")) {
@@ -66,7 +69,7 @@ public void setEnchantment(ItemStack stk, CustomEnchantment ench, int level, Wor
         }
         ItemMeta meta = stk.getItemMeta();
         List<String> lore = new LinkedList<>();
-        if (meta.hasLore()) {
+        if (meta.getLore() != null) {
             for (String loreStr : meta.getLore()) {
                 if (!loreStr.toLowerCase(Locale.ENGLISH).contains(ench.getLoreName().toLowerCase(Locale.ENGLISH))) {
                     lore.add(loreStr);

src/main/java/de/geolykt/enchantments_plus/compatibility/enchantmentgetters/PersistentDataGetter.java

@@ -7,6 +7,7 @@
 import org.bukkit.Material;
 import org.bukkit.World;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.Nullable;
 
 import de.geolykt.enchantments_plus.CustomEnchantment;
 
@@ -44,7 +45,7 @@ public PersistentDataGetter(EnumSet<Material> allowlist, boolean denylistToggle)
     }
 
     @Override
-    public LinkedHashMap<CustomEnchantment, Integer> getEnchants(ItemStack stk, boolean acceptBooks, World world,
+    public LinkedHashMap<CustomEnchantment, Integer> getEnchants(@Nullable ItemStack stk, boolean acceptBooks, World world,
             List<String> outExtraLore) {
         if (stk != null) {
             if (isGetterDenylist) {

src/main/java/de/geolykt/enchantments_plus/evt/NewAnvilMerger.java

@@ -13,6 +13,7 @@
 import org.bukkit.event.inventory.PrepareAnvilEvent;
 import org.bukkit.inventory.AnvilInventory;
 import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
 
 import de.geolykt.enchantments_plus.CustomEnchantment;
 import de.geolykt.enchantments_plus.compatibility.CompatibilityAdapter;
@@ -28,15 +29,16 @@ public class NewAnvilMerger implements Listener {
 
     /**
      * The remapping function used by {@link #mergeEnchantments(Map, Map)} to merge the levels of the same enchantments.
-     *  Default behavior (v2.1.5) results in the following: if Integer A and Integer B are the same and non-0, then A+1 is returned.
-     *  Otherwise the bigger of the two is returned.
-     * @param ench The enchantment that needs to be remapped, ignored per default
+     *  Default behaviour (v2.1.5) results in the following: if Integer A and Integer B are the same and non-0, then the smaller of A+1 or the maximum level
+     *   of the enchantment is returned.
+     *  Otherwise the bigger of the two input levels is returned.
+     * @param ench The enchantment that needs to be remapped, used to retrieve the maximum enchantment level
      * @param inputA The primary input level
      * @param inputB The secondary input level
      * @return Returns the new level of the Enchantment.
      * @since 2.1.5
      */
-    public static Integer enchantmentLevelRemappingFunction(CustomEnchantment ench, Integer inputA, Integer inputB) {
+    public static int enchantmentLevelRemappingFunction(@NotNull CustomEnchantment ench, Integer inputA, Integer inputB) {
         if (inputA != 0 && inputB != 0 && inputA == inputB) {
             return Math.min(inputA + 1, ench.getMaxLevel());
         } else {
@@ -91,7 +93,7 @@ public void prepareEvent(PrepareAnvilEvent evt) {
         if (inv.getSize() < 3 || evt.getViewers().size() == 0 || inv.getItem(0) == null)
             return;
         List<String> nleftLore = new ArrayList<String>();
-        if (evt.getResult() == null) {
+        if (evt.getResult() == null || evt.getResult().getType() == Material.AIR) {
             // Best guess merge
             ItemStack stackA = inv.getItem(0).clone();
             ItemStack stackB = inv.getItem(1);