Support Minecraft 1.13

Drops support for older Minecraft verions (1.8 - 1.12.2)

pom.xml

@@ -145,7 +145,7 @@
         <dependency>
             <groupId>org.bukkit</groupId>
             <artifactId>bukkit</artifactId>
-            <version>1.12-R0.1-SNAPSHOT</version>
+            <version>1.13-R0.1-SNAPSHOT</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
@@ -226,28 +226,14 @@
     </distributionManagement>
 
     <build>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <targetPath>.</targetPath>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
         <plugins>
-            <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-resources-plugin</artifactId>
-                <executions>
-                    <execution>
-                        <phase>prepare-package</phase>
-                        <goals>
-                            <goal>resources</goal>
-                        </goals>
-                    </execution>
-                </executions>
-                <configuration>
-                    <resources>
-                        <resource>
-                            <directory>src/main/resources</directory>
-                            <targetPath>.</targetPath>
-                            <filtering>true</filtering>
-                        </resource>
-                    </resources>
-                </configuration>
-            </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-shade-plugin</artifactId>

src/main/java/de/epiceric/shopchest/ShopChest.java

@@ -151,14 +151,7 @@ public class ShopChest extends JavaPlugin {
         }
 
         switch (Utils.getServerVersion()) {
-            case "v1_8_R1":
+            case "v1_13_R1":
-            case "v1_8_R2":
-            case "v1_8_R3":
-            case "v1_9_R1":
-            case "v1_9_R2":
-            case "v1_10_R1":
-            case "v1_11_R1":
-            case "v1_12_R1":
                 break;
             default:
                 debug("Server version not officially supported: " + Utils.getServerVersion() + "!");
@@ -360,10 +353,7 @@ public class ShopChest extends JavaPlugin {
         getServer().getPluginManager().registerEvents(new ShopInteractListener(this), this);
         getServer().getPluginManager().registerEvents(new NotifyPlayerOnJoinListener(this), this);
         getServer().getPluginManager().registerEvents(new ChestProtectListener(this, worldGuard), this);
-
+        getServer().getPluginManager().registerEvents(new BlockExplodeListener(this), this);
-        if (!Utils.getServerVersion().equals("v1_8_R1")) {
-            getServer().getPluginManager().registerEvents(new BlockExplodeListener(this), this);
-        }
 
         if (hasWorldGuard()) {
             getServer().getPluginManager().registerEvents(new WorldGuardListener(this), this);

src/main/java/de/epiceric/shopchest/language/BookGenerationName.java

@@ -1,13 +1,13 @@
 package de.epiceric.shopchest.language;
 
-import de.epiceric.shopchest.nms.CustomBookMeta;
+import org.bukkit.inventory.meta.BookMeta;
 
 public class BookGenerationName {
 
     private String localizedName;
-    private CustomBookMeta.Generation generation;
+    private BookMeta.Generation generation;
 
-    public BookGenerationName(CustomBookMeta.Generation generation, String localizedName) {
+    public BookGenerationName(BookMeta.Generation generation, String localizedName) {
         this.generation = generation;
         this.localizedName = localizedName;
     }
@@ -15,7 +15,7 @@ public class BookGenerationName {
     /**
      * @return Generation linked to the name
      */
-    public CustomBookMeta.Generation getGeneration() {
+    public BookMeta.Generation getGeneration() {
         return generation;
     }
 

src/main/java/de/epiceric/shopchest/language/ItemName.java

@@ -5,18 +5,10 @@ import org.bukkit.Material;
 public class ItemName {
 
     private Material material;
-    private int subID;
     private String localizedName;
 
-    public ItemName(Material material, int subID, String localizedName) {
-        this.material = material;
-        this.subID = subID;
-        this.localizedName = localizedName;
-    }
-
     public ItemName(Material material, String localizedName) {
         this.material = material;
-        this.subID = 0;
         this.localizedName = localizedName;
     }
 
@@ -27,13 +19,6 @@ public class ItemName {
         return material;
     }
 
-    /**
-     * @return Sub ID linked to the name
-     */
-    public int getSubID() {
-        return subID;
-    }
-
     /**
      * @return Name linked to the item
      */

src/main/java/de/epiceric/shopchest/language/PotionEffectName.java

@@ -1,13 +1,13 @@
 package de.epiceric.shopchest.language;
 
-import org.bukkit.potion.PotionType;
+import org.bukkit.potion.PotionEffectType;
 
 public class PotionEffectName {
 
-    private PotionType effect;
+    private PotionEffectType effect;
     private String localizedName;
 
-    public PotionEffectName(PotionType effect, String localizedName) {
+    public PotionEffectName(PotionEffectType effect, String localizedName) {
         this.effect = effect;
         this.localizedName = localizedName;
     }
@@ -15,7 +15,7 @@ public class PotionEffectName {
     /**
      * @return Potion Effect linked to the name
      */
-    public PotionType getEffect() {
+    public PotionEffectType getEffect() {
         return effect;
     }
 

src/main/java/de/epiceric/shopchest/listeners/ShopInteractListener.java

@@ -25,7 +25,6 @@ import de.epiceric.shopchest.external.WorldGuardShopFlag;
 import de.epiceric.shopchest.language.LanguageUtils;
 import de.epiceric.shopchest.language.Message;
 import de.epiceric.shopchest.language.Replacement;
-import de.epiceric.shopchest.nms.CustomBookMeta;
 import de.epiceric.shopchest.nms.Hologram;
 import de.epiceric.shopchest.shop.Shop;
 import de.epiceric.shopchest.shop.Shop.ShopType;
@@ -65,7 +64,6 @@ import org.bukkit.inventory.Inventory;
 import org.bukkit.inventory.InventoryHolder;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.PlayerInventory;
-import org.bukkit.inventory.meta.BookMeta;
 import org.bukkit.scheduler.BukkitRunnable;
 import pl.islandworld.api.IslandWorldApi;
 import us.talabrek.ultimateskyblock.api.IslandInfo;
@@ -346,6 +344,9 @@ public class ShopInteractListener implements Listener {
                         Shop shop = shopUtils.getShop(b.getLocation());
                         if (shop != null || ClickType.getPlayerClickType(p).getClickType() == ClickType.EnumClickType.CREATE) {
                             switch (ClickType.getPlayerClickType(p).getClickType()) {
+                                case CREATE:
+                                    break;
+                                    
                                 case INFO:
                                     e.setCancelled(true);
 
@@ -868,22 +869,8 @@ public class ShopInteractListener implements Listener {
         }
 
         if (type == Material.WRITTEN_BOOK) {
-            BookMeta meta = (BookMeta) shop.getProduct().getItemMeta();
-            CustomBookMeta.Generation generation = CustomBookMeta.Generation.TATTERED;
-
-            if ((Utils.getMajorVersion() == 9 && Utils.getRevision() == 1) || Utils.getMajorVersion() == 8) {
-                CustomBookMeta.Generation gen = CustomBookMeta.getGeneration(shop.getProduct());
-                generation = (gen == null ? CustomBookMeta.Generation.ORIGINAL : gen);
-            } else if (Utils.getMajorVersion() >= 10) {
-                if (meta.hasGeneration()) {
-                    generation = CustomBookMeta.Generation.valueOf(meta.getGeneration().toString());
-                } else {
-                    generation = CustomBookMeta.Generation.ORIGINAL;
-                }
-            }
-
             bookGenerationString = LanguageUtils.getMessage(Message.SHOP_INFO_BOOK_GENERATION,
-                    new Replacement(Placeholder.GENERATION, LanguageUtils.getBookGenerationName(generation)));
+                    new Replacement(Placeholder.GENERATION, LanguageUtils.getBookGenerationName(shop.getProduct())));
         }
 
         String musicDiscName = LanguageUtils.getMusicDiscName(type);

src/main/java/de/epiceric/shopchest/listeners/WorldGuardListener.java

@@ -64,6 +64,7 @@ public class WorldGuardListener implements Listener {
                     return query.testState(location, localPlayer, WorldGuardShopFlag.CREATE_SHOP);
                 case REMOVE:
                 case INFO:
+                case OPEN:
                     return true;
             }
         } else {

src/main/java/de/epiceric/shopchest/nms/ArmorStandWrapper.java

@@ -49,18 +49,13 @@ public class ArmorStandWrapper {
                 entityArmorStandClass.getMethod("setCustomNameVisible", boolean.class).invoke(entity, true);
             }
 
-            if (Utils.getMajorVersion() < 10) {
+            entityArmorStandClass.getMethod("setNoGravity", boolean.class).invoke(entity, true);
-                entityArmorStandClass.getMethod("setGravity", boolean.class).invoke(entity, false);
-            } else {
-                entityArmorStandClass.getMethod("setNoGravity", boolean.class).invoke(entity, true);
-            }
-
             entityArmorStandClass.getMethod("setInvisible", boolean.class).invoke(entity, true);
 
             // Adds the entity to some lists so it can call interact events
             // It will also automatically load/unload it when far away
             if (interactable) {
-                Method addEntityMethod = worldServerClass.getDeclaredMethod((Utils.getMajorVersion() == 8 ? "a" : "b"), entityClass);
+                Method addEntityMethod = worldServerClass.getDeclaredMethod("b", entityClass);
                 addEntityMethod.setAccessible(true);
                 addEntityMethod.invoke(worldServerClass.cast(nmsWorld), entity);
             }
@@ -147,7 +142,7 @@ public class ArmorStandWrapper {
 
         try {
             // Removes the entity from the lists it was added to for interaction
-            Method addEntityMethod = worldServerClass.getDeclaredMethod((Utils.getMajorVersion() == 8 ? "b" : "c"), entityClass);
+            Method addEntityMethod = worldServerClass.getDeclaredMethod("c", entityClass);
             addEntityMethod.setAccessible(true);
             addEntityMethod.invoke(worldServerClass.cast(nmsWorld), entity);
         } catch (ReflectiveOperationException e) {

src/main/java/de/epiceric/shopchest/nms/CustomBookMeta.java

@@ -1,90 +0,0 @@
-package de.epiceric.shopchest.nms;
-
-import de.epiceric.shopchest.ShopChest;
-import de.epiceric.shopchest.utils.Utils;
-import org.bukkit.inventory.ItemStack;
-
-import java.lang.reflect.InvocationTargetException;
-
-// For versions below 1.9.4, since Bukkit's BookMeta
-// didn't have generations in those versions
-
-public class CustomBookMeta {
-
-    public enum Generation {
-        ORIGINAL,
-        COPY_OF_ORIGINAL,
-        COPY_OF_COPY,
-        TATTERED
-    }
-
-    public static Generation getGeneration(ItemStack book) {
-        try {
-            Class<?> craftItemStackClass = Utils.getCraftClass("inventory.CraftItemStack");
-
-            if (craftItemStackClass == null) {
-                ShopChest.getInstance().debug("Failed to get NBTGeneration: Could not find CraftItemStack class");
-                return null;
-            }
-
-            Object nmsStack = craftItemStackClass.getMethod("asNMSCopy", ItemStack.class).invoke(null, book);
-
-            Object nbtTagCompound = nmsStack.getClass().getMethod("getTag").invoke(nmsStack);
-            if (nbtTagCompound == null) {
-                ShopChest.getInstance().debug("Failed to get NBTGeneration: getTag returned null");
-                return null;
-            }
-
-            Object generationObject = nbtTagCompound.getClass().getMethod("getInt", String.class).invoke(nbtTagCompound, "generation");
-            if (generationObject == null) {
-                ShopChest.getInstance().debug("Failed to get NBTGeneration: getInt returned null");
-                return null;
-            }
-
-            if (generationObject instanceof Integer) {
-                int generation = (Integer) generationObject;
-
-                if (generation > 3) generation = 3;
-
-                return Generation.values()[generation];
-            }
-
-        } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
-            ShopChest.getInstance().getLogger().severe("Failed to get NBTEntityID with reflection");
-            ShopChest.getInstance().debug("Failed to get NBTEntityID with reflection");
-            ShopChest.getInstance().debug(e);
-        }
-
-        return null;
-    }
-
-    public static void setGeneration(ItemStack book, Generation generation) {
-        try {
-            Class<?> craftItemStackClass = Utils.getCraftClass("inventory.CraftItemStack");
-
-            if (craftItemStackClass == null) {
-                ShopChest.getInstance().debug("Failed to get NBTGeneration: Could not find CraftItemStack class");
-                return;
-            }
-
-            Object nmsStack = craftItemStackClass.getMethod("asNMSCopy", ItemStack.class).invoke(null, book);
-
-            Object nbtTagCompound = nmsStack.getClass().getMethod("getTag").invoke(nmsStack);
-            if (nbtTagCompound == null) {
-                ShopChest.getInstance().debug("Failed to get NBTGeneration: getTag returned null");
-                return;
-            }
-
-            nbtTagCompound.getClass().getMethod("setInt", String.class, int.class)
-                    .invoke(nbtTagCompound, "generation", generation.ordinal());
-
-            nmsStack.getClass().getMethod("setTag", nbtTagCompound.getClass()).invoke(nmsStack, nbtTagCompound);
-
-        } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
-            ShopChest.getInstance().getLogger().severe("Failed to get NBTEntityID with reflection");
-            ShopChest.getInstance().debug("Failed to get NBTEntityID with reflection");
-            ShopChest.getInstance().debug(e);
-        }
-    }
-
-}

src/main/java/de/epiceric/shopchest/nms/JsonBuilder.java

@@ -17,22 +17,16 @@ public class JsonBuilder {
 
     private Class<?> iChatBaseComponentClass = Utils.getNMSClass("IChatBaseComponent");
     private Class<?> packetPlayOutChatClass = Utils.getNMSClass("PacketPlayOutChat");
-    private Class<?> chatSerializerClass;
+    private Class<?> chatSerializerClass = Utils.getNMSClass("IChatBaseComponent$ChatSerializer");;
 
     public JsonBuilder(ShopChest plugin, String text, String hoverText, String downloadLink) {
         this.plugin = plugin;
 
-        if (Utils.getServerVersion().equals("v1_8_R1")) {
+        Class<?>[] requiredClasses = new Class<?>[] {
-            chatSerializerClass = Utils.getNMSClass("ChatSerializer");
-        } else {
-            chatSerializerClass = Utils.getNMSClass("IChatBaseComponent$ChatSerializer");
-        }
-
-        Class[] requiredClasses = new Class[] {
           iChatBaseComponentClass, packetPlayOutChatClass, chatSerializerClass
         };
 
-        for (Class c : requiredClasses) {
+        for (Class<?> c : requiredClasses) {
             if (c == null) {
                 plugin.debug("Failed to instantiate JsonBuilder: Could not find all required classes");
                 return;

src/main/java/de/epiceric/shopchest/nms/SpawnEggMeta.java

@@ -1,89 +0,0 @@
-package de.epiceric.shopchest.nms;
-
-import de.epiceric.shopchest.ShopChest;
-import de.epiceric.shopchest.utils.Utils;
-import org.bukkit.entity.EntityType;
-import org.bukkit.inventory.ItemStack;
-
-import java.lang.reflect.InvocationTargetException;
-
-public class SpawnEggMeta {
-
-    private static String getNBTEntityID(ShopChest plugin, ItemStack stack) {
-        try {
-            Class<?> craftItemStackClass = Utils.getCraftClass("inventory.CraftItemStack");
-
-            if (craftItemStackClass == null) {
-                plugin.debug("Failed to get NBTEntityID: Could not find CraftItemStack class");
-                return null;
-            }
-
-            Object nmsStack = craftItemStackClass.getMethod("asNMSCopy", ItemStack.class).invoke(null, stack);
-
-            Object nbtTagCompound = nmsStack.getClass().getMethod("getTag").invoke(nmsStack);
-            if (nbtTagCompound == null) return null;
-
-            Object entityTagCompound = nbtTagCompound.getClass().getMethod("getCompound", String.class).invoke(nbtTagCompound, "EntityTag");
-            if (entityTagCompound == null) return null;
-
-            Object id = entityTagCompound.getClass().getMethod("getString", String.class).invoke(entityTagCompound, "id");
-            if (id instanceof String) return (String) id;
-
-        } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
-            plugin.getLogger().severe("Failed to get NBTEntityID with reflection");
-            plugin.debug("Failed to get NBTEntityID with reflection");
-            plugin.debug(e);
-        }
-
-        return null;
-    }
-
-    /**
-     * @param stack {@link ItemStack} (Spawn Egg) of which the Entity should be gotten
-     * @return The {@link EntityType} the Spawn Egg will spawn or <b>null</b> if <i>nbtEntityID</i> is null
-     */
-    public static EntityType getEntityTypeFromItemStack(ShopChest plugin, ItemStack stack) {
-        if (Utils.getMajorVersion() == 8) {
-            EntityType type = null;
-
-            for (EntityType entityType : EntityType.values()) {
-                if (entityType.getTypeId() == stack.getDurability()) {
-                    type = entityType;
-                    break;
-                }
-            }
-
-            return type;
-        }
-
-        String nbtEntityID = getNBTEntityID(plugin, stack);
-
-        if (nbtEntityID == null) return null;
-
-        if (Utils.getMajorVersion() >= 11) {
-            if (nbtEntityID.contains(":")) nbtEntityID = nbtEntityID.split(":")[1];
-            return EntityType.fromName(nbtEntityID);
-        }
-
-        switch (nbtEntityID) {
-            case "PigZombie":
-                return EntityType.PIG_ZOMBIE;
-            case "CaveSpider":
-                return EntityType.CAVE_SPIDER;
-            case "LavaSlime":
-                return EntityType.MAGMA_CUBE;
-            case "MushroomCow":
-                return EntityType.MUSHROOM_COW;
-            case "EntityHorse":
-                return EntityType.HORSE;
-            case "PolarBear":
-                return EntityType.POLAR_BEAR;
-            case "Ozelot":
-                return EntityType.OCELOT;
-            default:
-                return EntityType.valueOf(nbtEntityID.toUpperCase());
-
-        }
-    }
-
-}

src/main/java/de/epiceric/shopchest/shop/Shop.java

@@ -216,9 +216,9 @@ public class Shop {
         requirements.put(HologramFormat.Requirement.BUY_PRICE, getBuyPrice());
         requirements.put(HologramFormat.Requirement.SELL_PRICE, getSellPrice());
         requirements.put(HologramFormat.Requirement.HAS_POTION_EFFECT, ItemUtils.getPotionEffect(getProduct()) != null);
-        requirements.put(HologramFormat.Requirement.IS_MUSIC_DISC, ItemUtils.isMusicDisc(getProduct()));
+        requirements.put(HologramFormat.Requirement.IS_MUSIC_DISC, getProduct().getType().isRecord());
         requirements.put(HologramFormat.Requirement.IS_POTION_EXTENDED, ItemUtils.isExtendedPotion(getProduct()));
-        requirements.put(HologramFormat.Requirement.IS_WRITTEN_BOOK, ItemUtils.getBookGeneration(getProduct()) != null);
+        requirements.put(HologramFormat.Requirement.IS_WRITTEN_BOOK, getProduct().getType() == Material.WRITTEN_BOOK);
         requirements.put(HologramFormat.Requirement.ADMIN_SHOP, getShopType() == ShopType.ADMIN);
         requirements.put(HologramFormat.Requirement.NORMAL_SHOP, getShopType() == ShopType.NORMAL);
         requirements.put(HologramFormat.Requirement.IN_STOCK, Utils.getAmount(getInventoryHolder().getInventory(), getProduct()));
@@ -235,7 +235,7 @@ public class Shop {
         placeholders.put(Placeholder.SELL_PRICE, getSellPrice());
         placeholders.put(Placeholder.POTION_EFFECT, LanguageUtils.getPotionEffectName(getProduct()));
         placeholders.put(Placeholder.MUSIC_TITLE, LanguageUtils.getMusicDiscName(getProduct().getType()));
-        placeholders.put(Placeholder.GENERATION, LanguageUtils.getBookGenerationName(ItemUtils.getBookGeneration(getProduct())));
+        placeholders.put(Placeholder.GENERATION, LanguageUtils.getBookGenerationName(getProduct()));
         placeholders.put(Placeholder.STOCK, Utils.getAmount(getInventoryHolder().getInventory(), getProduct()));
         placeholders.put(Placeholder.MAX_STACK, getProduct().getMaxStackSize());
         placeholders.put(Placeholder.CHEST_SPACE, Utils.getFreeSpaceForItem(getInventoryHolder().getInventory(), getProduct()));

src/main/java/de/epiceric/shopchest/utils/ItemUtils.java

@@ -1,16 +1,12 @@
 package de.epiceric.shopchest.utils;
 
-import com.google.common.collect.Lists;
-import de.epiceric.shopchest.nms.CustomBookMeta;
 import org.bukkit.Material;
 import org.bukkit.enchantments.Enchantment;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.EnchantmentStorageMeta;
 import org.bukkit.inventory.meta.PotionMeta;
-import org.bukkit.potion.Potion;
 import org.bukkit.potion.PotionType;
 
-import java.util.List;
 import java.util.Map;
 
 public class ItemUtils {
@@ -25,12 +21,8 @@ public class ItemUtils {
     }
 
     public static PotionType getPotionEffect(ItemStack itemStack) {
-        if (itemStack.getItemMeta() instanceof PotionMeta) {
+        if (itemStack.getItemMeta() instanceof PotionMeta) {    
-            if (Utils.getMajorVersion() < 9) {
+            return ((PotionMeta) itemStack.getItemMeta()).getBasePotionData().getType();
-                return Potion.fromItemStack(itemStack).getType();
-            } else {
-                return ((PotionMeta) itemStack.getItemMeta()).getBasePotionData().getType();
-            }
         }
 
         return null;
@@ -38,36 +30,13 @@ public class ItemUtils {
 
     public static boolean isExtendedPotion(ItemStack itemStack) {
         if (itemStack.getItemMeta() instanceof PotionMeta) {
-            if (Utils.getMajorVersion() >= 9) {
+            PotionMeta potionMeta = (PotionMeta) itemStack.getItemMeta();
-                PotionMeta potionMeta = (PotionMeta) itemStack.getItemMeta();
+            return potionMeta.getBasePotionData().isExtended();
-                return potionMeta.getBasePotionData().isExtended();
-            } else {
-                Potion potion = Potion.fromItemStack(itemStack);
-                return potion.hasExtendedDuration();
-            }
         }
 
         return false;
     }
 
-    public static boolean isMusicDisc(ItemStack itemStack) {
-        List<Material> musicDiscMaterials = Lists.newArrayList(
-                Material.GOLD_RECORD, Material.GREEN_RECORD, Material.RECORD_3, Material.RECORD_4,
-                Material.RECORD_5, Material.RECORD_6, Material.RECORD_7, Material.RECORD_8,
-                Material.RECORD_9, Material.RECORD_10, Material.RECORD_11, Material.RECORD_12
-        );
-
-        return musicDiscMaterials.contains(itemStack.getType());
-    }
-
-    public static CustomBookMeta.Generation getBookGeneration(ItemStack itemStack) {
-        if (itemStack.getType() == Material.WRITTEN_BOOK) {
-            return CustomBookMeta.getGeneration(itemStack);
-        }
-
-        return null;
-    }
-
     /**
      * Get the {@link ItemStack} from a String
      * @param item Serialized ItemStack e.g. {@code "STONE"} or {@code "STONE:1"}

src/main/java/de/epiceric/shopchest/utils/UpdateChecker.java

@@ -51,7 +51,7 @@ public class UpdateChecker {
                 return UpdateCheckerResult.TRUE;
             }
 
-        } catch (IOException e) {
+        } catch (Exception e) {
             plugin.debug("Failed to check for updates");
             plugin.debug(e);
             return UpdateCheckerResult.ERROR;

src/main/java/de/epiceric/shopchest/utils/Utils.java

@@ -4,7 +4,6 @@ import com.intellectualcrafters.plot.flag.Flag;
 import com.intellectualcrafters.plot.object.Plot;
 import de.epiceric.shopchest.ShopChest;
 import de.epiceric.shopchest.external.PlotSquaredShopFlag;
-import de.epiceric.shopchest.nms.CustomBookMeta;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.configuration.InvalidConfigurationException;
@@ -43,17 +42,8 @@ public class Utils {
             BookMeta bookMeta1 = (BookMeta) itemStack1.getItemMeta();
             BookMeta bookMeta2 = (BookMeta) itemStack2.getItemMeta();
 
-            if ((getMajorVersion() == 9 && getRevision() == 1) || getMajorVersion() == 8) {
+            if (bookMeta1.getGeneration() == null) bookMeta1.setGeneration(BookMeta.Generation.ORIGINAL);
-                CustomBookMeta.Generation generation1 = CustomBookMeta.getGeneration(itemStack1);
+            if (bookMeta2.getGeneration() == null) bookMeta2.setGeneration(BookMeta.Generation.ORIGINAL);
-                CustomBookMeta.Generation generation2 = CustomBookMeta.getGeneration(itemStack2);
-
-                if (generation1 == null) CustomBookMeta.setGeneration(itemStack1, CustomBookMeta.Generation.ORIGINAL);
-                if (generation2 == null) CustomBookMeta.setGeneration(itemStack2, CustomBookMeta.Generation.ORIGINAL);
-
-            } else if (getMajorVersion() >= 10) {
-                if (bookMeta1.getGeneration() == null) bookMeta1.setGeneration(BookMeta.Generation.ORIGINAL);
-                if (bookMeta2.getGeneration() == null) bookMeta2.setGeneration(BookMeta.Generation.ORIGINAL);
-            }
 
             itemStack1.setItemMeta(bookMeta1);
             itemStack2.setItemMeta(bookMeta2);
@@ -75,14 +65,10 @@ public class Utils {
         ArrayList<ItemStack> inventoryItems = new ArrayList<>();
 
         if (inventory instanceof PlayerInventory) {
-            if (getMajorVersion() >= 9) {
+            for (int i = 0; i < 37; i++) {
-                inventoryItems.add(inventory.getItem(40));
+                if (i == 36) i = 40;
-            }
-
-            for (int i = 0; i < 36; i++) {
                 inventoryItems.add(inventory.getItem(i));
             }
-
         } else {
             for (int i = 0; i < inventory.getSize(); i++) {
                 inventoryItems.add(inventory.getItem(i));
@@ -109,7 +95,9 @@ public class Utils {
         HashMap<Integer, Integer> slotFree = new HashMap<>();
 
         if (inventory instanceof PlayerInventory) {
-            for (int i = 0; i < 36; i++) {
+            for (int i = 0; i < 37; i++) {
+                if (i == 36) i = 40;
+
                 ItemStack item = inventory.getItem(i);
                 if (item == null || item.getType() == Material.AIR) {
                     slotFree.put(i, itemStack.getMaxStackSize());
@@ -121,19 +109,6 @@ public class Utils {
                     }
                 }
             }
-
-            if (getMajorVersion() >= 9) {
-                ItemStack item = inventory.getItem(40);
-                if (item == null || item.getType() == Material.AIR) {
-                    slotFree.put(40, itemStack.getMaxStackSize());
-                } else {
-                    if (isItemSimilar(item, itemStack)) {
-                        int amountInSlot = item.getAmount();
-                        int amountToFullStack = itemStack.getMaxStackSize() - amountInSlot;
-                        slotFree.put(40, amountToFullStack);
-                    }
-                }
-            }
         } else {
             for (int i = 0; i < inventory.getSize(); i++) {
                 ItemStack item = inventory.getItem(i);
@@ -162,17 +137,10 @@ public class Utils {
      * @return {@link ItemStack} in his main hand, or {@code null} if he doesn't hold one
      */
     public static ItemStack getItemInMainHand(Player p) {
-        if (getMajorVersion() < 9) {
+        if (p.getInventory().getItemInMainHand().getType() == Material.AIR)
-            if (p.getItemInHand().getType() == Material.AIR)
+            return null;
-                return null;
+        else
-            else
+            return p.getInventory().getItemInMainHand();
-                return p.getItemInHand();
-        } else {
-            if (p.getInventory().getItemInMainHand().getType() == Material.AIR)
-                return null;
-            else
-                return p.getInventory().getItemInMainHand();
-        }
     }
 
     /**
@@ -180,14 +148,10 @@ public class Utils {
      * @return {@link ItemStack} in his off hand, or {@code null} if he doesn't hold one or the server version is below 1.9
      */
     public static ItemStack getItemInOffHand(Player p) {
-        if (getMajorVersion() < 9) {
+        if (p.getInventory().getItemInOffHand().getType() == Material.AIR)
             return null;
-        } else {
+        else
-            if (p.getInventory().getItemInOffHand().getType() == Material.AIR)
+            return p.getInventory().getItemInOffHand();
-                return null;
-            else
-                return p.getInventory().getItemInOffHand();
-        }
     }
 
     /**
@@ -196,14 +160,10 @@ public class Utils {
      *         if he doesn't have one in both hands
      */
     public static ItemStack getPreferredItemInHand(Player p) {
-        if (getMajorVersion() < 9) {
+        if (getItemInMainHand(p) != null)
             return getItemInMainHand(p);
-        } else {
+        else
-            if (getItemInMainHand(p) != null)
+            return getItemInOffHand(p);
-                return getItemInMainHand(p);
-            else
-                return getItemInOffHand(p);
-        }
     }
 
     /**
@@ -211,7 +171,7 @@ public class Utils {
      * @return Whether a player has an axe in one of his hands
      */
     public static boolean hasAxeInHand(Player p) {
-        List<Material> axes = Arrays.asList(Material.WOOD_AXE, Material.STONE_AXE, Material.IRON_AXE, Material.GOLD_AXE, Material.DIAMOND_AXE);
+        List<Material> axes = Arrays.asList(Material.WOODEN_AXE, Material.STONE_AXE, Material.IRON_AXE, Material.GOLDEN_AXE, Material.DIAMOND_AXE);
 
         ItemStack item = getItemInMainHand(p);
         if (item == null || !axes.contains(item.getType())) {

src/main/resources/plugin.yml

@@ -8,6 +8,7 @@ website: ${project.url}
 description: Create your own nice-looking chest shops and sell your stuff to other players!
 softdepend: [WorldGuard, Towny, AuthMe, PlotSquared, uSkyBlock, ASkyBlock, IslandWorld, GriefPrevention, AreaShop, Multiverse-Core, MultiWorld]
 depend: [Vault]
+api-version: 1.13
 
 permissions:
   shopchest.*: