Merge pull request #30 from TheSilentPro/patches

Patches 4.2.2

.github/workflows/sonarcloud.yml

@@ -1,4 +1,4 @@
-name: SonarCLoud Scanner
+name: SonarCloud Scanner
 on:
   push:
     branches:

pom.xml

@@ -13,6 +13,8 @@
         <sonar.projectKey>TheSilentPro_HeadDB</sonar.projectKey>
         <sonar.organization>silent</sonar.organization>
         <sonar.host.url>https://sonarcloud.io</sonar.host.url>
+        <sonar.exclusions>src/main/java/tsp/headdb/Metrics.java</sonar.exclusions>
+        <sonar.coverage.exclusions>*</sonar.coverage.exclusions>
         <spigot.id>84967</spigot.id>
     </properties>
 

src/main/java/tsp/headdb/HeadDB.java

@@ -67,7 +67,7 @@ public class HeadDB extends JavaPlugin {
         initMetrics();
 
         Utils.isLatestVersion(this, 84967, latest -> {
-            if (!latest) {
+            if (!Boolean.TRUE.equals(latest)) {
                 Log.warning("There is a new update available for HeadDB on spigot!");
                 Log.warning("Download: https://www.spigotmc.org/resources/84967");
             }
@@ -112,10 +112,6 @@ public class HeadDB extends JavaPlugin {
 
     private void initMetrics() {
         Metrics metrics = new Metrics(this, 9152);
-        if (!metrics.isEnabled()) {
-            Log.debug("Metrics are disabled.");
-            return;
-        }
 
         metrics.addCustomChart(new Metrics.SimplePie("economy_provider", () -> {
             if (this.getEconomyProvider() != null) {

src/main/java/tsp/headdb/api/HeadAPI.java

@@ -2,7 +2,6 @@ package tsp.headdb.api;
 
 import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
-import org.bukkit.OfflinePlayer;
 import org.bukkit.entity.Player;
 import tsp.headdb.HeadDB;
 import tsp.headdb.implementation.Category;
@@ -14,8 +13,8 @@ import tsp.headdb.storage.PlayerDataFile;
 
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
-import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.UUID;
 import java.util.stream.Collectors;
 
@@ -29,6 +28,11 @@ public final class HeadAPI {
 
     private HeadAPI() {}
 
+    private static final String VALIDATION_PLAYER_NULL = "Player can not be null!";
+    private static final String VALIDATION_CATEGORY_NULL = "Category can not be null!";
+    private static final String VALIDATION_UUID_NULL = "UUID can not be null!";
+    private static final String VALIDATION_VALUE_NULL = "Value can not be null!";
+
     /**
      * Main {@link HeadDatabase} that he HeadDB plugin uses.
      */
@@ -49,7 +53,7 @@ public final class HeadAPI {
      * @param player Target player
      */
     public static void openDatabase(@Nonnull Player player) {
-        Validate.notNull(player, "Player can not be null!");
+        Validate.notNull(player, VALIDATION_PLAYER_NULL);
 
         InventoryUtils.openDatabase(player);
     }
@@ -61,8 +65,8 @@ public final class HeadAPI {
      * @param category Category to open
      */
     public static void openCategoryDatabase(@Nonnull Player player, @Nonnull Category category) {
-        Validate.notNull(player, "Player can not be null!");
+        Validate.notNull(player, VALIDATION_PLAYER_NULL);
-        Validate.notNull(category, "Category can not be null!");
+        Validate.notNull(category, VALIDATION_CATEGORY_NULL);
 
         InventoryUtils.openCategoryDatabase(player, category);
     }
@@ -74,7 +78,7 @@ public final class HeadAPI {
      * @param search Search term
      */
     public static void openSearchDatabase(@Nonnull Player player, @Nonnull String search) {
-        Validate.notNull(player, "Player can not be null!");
+        Validate.notNull(player, VALIDATION_PLAYER_NULL);
         Validate.notNull(search, "Search can not be null!");
 
         InventoryUtils.openSearchDatabase(player, search);
@@ -87,7 +91,7 @@ public final class HeadAPI {
      * @param tag Tag search term
      */
     public static void openTagSearchDatabase(@Nonnull Player player, @Nonnull String tag) {
-        Validate.notNull(player, "Player can not be null!");
+        Validate.notNull(player, VALIDATION_PLAYER_NULL);
         Validate.notNull(tag, "Tag can not be null!");
 
         InventoryUtils.openTagSearchDatabase(player, tag);
@@ -112,7 +116,7 @@ public final class HeadAPI {
      */
     @Nullable
     public static Head getHeadByUniqueId(@Nonnull UUID uuid) {
-        Validate.notNull(uuid, "UUID can not be null!");
+        Validate.notNull(uuid, VALIDATION_UUID_NULL);
 
         return database.getHeadByUniqueId(uuid);
     }
@@ -152,7 +156,7 @@ public final class HeadAPI {
      */
     @Nonnull
     public static List<Head> getHeadsByName(@Nonnull Category category, @Nonnull String name) {
-        Validate.notNull(category, "Category can not be null!");
+        Validate.notNull(category, VALIDATION_CATEGORY_NULL);
         Validate.notNull(name, "Name can not be null!");
 
         return database.getHeadsByName(category, name);
@@ -166,7 +170,7 @@ public final class HeadAPI {
      */
     @Nullable
     public static Head getHeadByValue(@Nonnull String value) {
-        Validate.notNull(value, "Value can not be null!");
+        Validate.notNull(value, VALIDATION_VALUE_NULL);
 
         return database.getHeadByValue(value);
     }
@@ -179,7 +183,7 @@ public final class HeadAPI {
      */
     @Nonnull
     public static List<Head> getHeads(@Nonnull Category category) {
-        Validate.notNull(category, "Category can not be null!");
+        Validate.notNull(category, VALIDATION_CATEGORY_NULL);
 
         return database.getHeads(category);
     }
@@ -201,8 +205,8 @@ public final class HeadAPI {
      * @param textureValue The head's texture value
      */
     public static void addFavoriteHead(@Nonnull UUID uuid, @Nonnull String textureValue) {
-        Validate.notNull(uuid, "UUID can not be null!");
+        Validate.notNull(uuid, VALIDATION_UUID_NULL);
-        Validate.notNull(textureValue, "Value can not be null!");
+        Validate.notNull(textureValue, VALIDATION_VALUE_NULL);
 
         HeadDB.getInstance().getPlayerData().modifyFavorite(uuid, textureValue, PlayerDataFile.ModificationType.SET);
     }
@@ -214,8 +218,8 @@ public final class HeadAPI {
      * @param textureValue The head's texture value
      */
     public static void removeFavoriteHead(@Nonnull UUID uuid, @Nonnull String textureValue) {
-        Validate.notNull(uuid, "UUID can not be null!");
+        Validate.notNull(uuid, VALIDATION_UUID_NULL);
-        Validate.notNull(textureValue, "Value can not be null!");
+        Validate.notNull(textureValue, VALIDATION_VALUE_NULL);
 
         HeadDB.getInstance().getPlayerData().modifyFavorite(uuid, textureValue, PlayerDataFile.ModificationType.REMOVE);
     }
@@ -228,12 +232,12 @@ public final class HeadAPI {
      */
     @Nonnull
     public static List<Head> getFavoriteHeads(@Nonnull UUID uuid) {
-        Validate.notNull(uuid, "UUID can not be null!");
+        Validate.notNull(uuid, VALIDATION_UUID_NULL);
 
         return HeadDB.getInstance().getPlayerData().getFavoriteHeadsByTexture(uuid).stream()
                 .map(HeadAPI::getHeadByValue)
-                .filter(head -> head != null)
+                .filter(Objects::nonNull)
-                .collect(Collectors.toList());
+                .toList();
     }
 
     /**
@@ -248,7 +252,7 @@ public final class HeadAPI {
         return HeadDB.getInstance().getPlayerData().getEntries().stream()
                 .map(entry -> Bukkit.getOfflinePlayer(UUID.fromString(entry)))
                 .map(player -> new LocalHead(player.getUniqueId()).name(player.getName()))
-                .collect(Collectors.toList());
+                .toList();
     }
 
 }

src/main/java/tsp/headdb/command/HeadDBCommand.java

@@ -11,23 +11,21 @@ import tsp.headdb.util.Utils;
 
 public class HeadDBCommand implements CommandExecutor {
 
-    @Override
+    private void handle(CommandSender sender, String[] args) {
-    public boolean onCommand(CommandSender sender, Command command, String s, String[] args) {
         Localization localization = HeadDB.getInstance().getLocalization();
         if (args.length == 0) {
             if (!sender.hasPermission("headdb.open")) {
                 Utils.sendMessage(sender, localization.getMessage("noPermission"));
-                return true;
+                return;
             }
-            if (!(sender instanceof Player)) {
+            if (!(sender instanceof Player player)) {
                 Utils.sendMessage(sender, localization.getMessage("onlyPlayers"));
-                return true;
+                return;
             }
-            Player player = (Player) sender;
 
             Utils.sendMessage(player, localization.getMessage("databaseOpen"));
             HeadAPI.openDatabase(player);
-            return true;
+            return;
         }
 
         String sub = args[0];
@@ -48,7 +46,7 @@ public class HeadDBCommand implements CommandExecutor {
 
         if (subCommand != null) {
             subCommand.handle(sender, args);
-            return true;
+            return;
         }
 
         Utils.sendMessage(sender, " ");
@@ -62,6 +60,11 @@ public class HeadDBCommand implements CommandExecutor {
         Utils.sendMessage(sender, "&7 > &c/hdb update &9(u) &7- Forcefully update the database");
         Utils.sendMessage(sender, "&7 > &c/hdb give &9(g) &c<id> <player> &6[amount] &7- Give player a head");
         Utils.sendMessage(sender, " ");
+    }
+
+    @Override
+    public boolean onCommand(CommandSender sender, Command command, String s, String[] args) {
+        handle(sender, args);
         return true;
     }
 

src/main/java/tsp/headdb/command/SearchCommand.java

@@ -13,11 +13,10 @@ public class SearchCommand implements HeadSubCommand {
             Utils.sendMessage(sender, getLocalization().getMessage("noPermission"));
             return;
         }
-        if (!(sender instanceof Player)) {
+        if (!(sender instanceof Player player)) {
             Utils.sendMessage(sender, getLocalization().getMessage("onlyPlayers"));
             return;
         }
-        Player player = (Player) sender;
 
         if (args.length < 2) {
             Utils.sendMessage(player, "&c/hdb search <name>");
@@ -34,7 +33,6 @@ public class SearchCommand implements HeadSubCommand {
         String name = builder.toString();
         Utils.sendMessage(sender, "&7Searching for &e" + name);
         HeadAPI.openSearchDatabase(player, name);
-        return;
     }
     
 }

src/main/java/tsp/headdb/command/TagSearchCommand.java

@@ -19,16 +19,14 @@ public class TagSearchCommand implements HeadSubCommand {
             return;
         }
 
-        if (!(sender instanceof Player)) {
+        if (!(sender instanceof Player player)) {
             Utils.sendMessage(sender, getLocalization().getMessage("onlyPlayers"));
             return;
         }
 
-        Player player = (Player) sender;
         String tag = args[1];
         Utils.sendMessage(sender, "&7Searching for heads with tag &e" + tag);
         HeadAPI.openTagSearchDatabase(player, tag);
-        return;
     }
     
 }

src/main/java/tsp/headdb/economy/TreasuryProvider.java

@@ -34,16 +34,14 @@ public class TreasuryProvider implements BasicEconomyProvider {
         EconomySubscriber
                 .<Boolean>asFuture(s -> provider.hasPlayerAccount(player.getUniqueId(), s))
                 .thenCompose(val -> {
-                    if (val) {
+                    if (Boolean.TRUE.equals(val)) {
                         return EconomySubscriber.<PlayerAccount>asFuture(s -> provider.retrievePlayerAccount(player.getUniqueId(), s));
                     } else {
                         return EconomySubscriber.<PlayerAccount>asFuture(s -> provider.createPlayerAccount(player.getUniqueId(), s));
                     }
                 })
                 .thenCompose(account -> EconomySubscriber.<BigDecimal>asFuture(s -> account.retrieveBalance(currency, s)))
-                .whenComplete((bal, ex) -> {
+                .whenComplete((bal, ex) -> result.accept(bal.compareTo(cost) >= 0));
-                    result.accept(bal.compareTo(cost) >= 0);
-                });
     }
 
     @Override
@@ -51,13 +49,12 @@ public class TreasuryProvider implements BasicEconomyProvider {
         EconomySubscriber
                 .<Boolean>asFuture(s -> provider.hasPlayerAccount(player.getUniqueId(), s))
                 .thenCompose(val -> {
-                    if (val) {
+                    if (Boolean.TRUE.equals(val)) {
                         return EconomySubscriber.<PlayerAccount>asFuture(s -> provider.retrievePlayerAccount(player.getUniqueId(), s));
                     } else {
                         return EconomySubscriber.<PlayerAccount>asFuture(s -> provider.createPlayerAccount(player.getUniqueId(), s));
                     }
-                }).whenComplete((account, ex) -> {
+                }).whenComplete((account, ex) -> account.withdrawBalance(
-                    account.withdrawBalance(
                         amount,
                         transactionInitiator,
                         currency,
@@ -70,10 +67,9 @@ public class TreasuryProvider implements BasicEconomyProvider {
                             @Override
                             public void fail(@NotNull EconomyException exception) {
                                 result.accept(false);
-                                    exception.printStackTrace();
+                                Log.error(ex);
                             }
-                            });
+                        }));
-                });
     }
 
     @Override
@@ -92,9 +88,10 @@ public class TreasuryProvider implements BasicEconomyProvider {
         if (rawCurrency == null || rawCurrency.isEmpty()) {
             currency = provider.getPrimaryCurrency();
         } else {
-            currency = provider.getCurrencies().stream()
+            provider.getCurrencies().stream()
                     .filter(currency -> currency.getIdentifier().equalsIgnoreCase(rawCurrency))
-                    .findFirst().get();
+                    .findFirst()
+                    .ifPresentOrElse(c -> currency = c, () -> Log.error("Could not find currency: " + rawCurrency));
         }
     }
 

src/main/java/tsp/headdb/implementation/Category.java

@@ -1,12 +1,13 @@
 package tsp.headdb.implementation;
 
 import org.bukkit.ChatColor;
+import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 import tsp.headdb.api.HeadAPI;
 
 import javax.annotation.Nullable;
-import java.util.HashMap;
+import java.util.Objects;
-import java.util.Map;
+import java.util.Optional;
 
 /**
  * Represents a category for heads
@@ -29,8 +30,7 @@ public enum Category {
     private final String name;
     private final ChatColor color;
     private final int location;
-    private final Map<Category, Head> item = new HashMap<>();
+    private static final Category[] cache = values();
-    public static final Category[] cache = values();
 
     Category(String name, ChatColor color, int location) {
         this.name = name;
@@ -56,9 +56,15 @@ public enum Category {
      * @return First valid head
      */
     public ItemStack getItem() {
-        return HeadAPI.getHeads(this).stream()
+        Optional<Head> result = HeadAPI.getHeads(this).stream()
-                .filter(head -> head != null)
+                .filter(Objects::nonNull)
-                .findFirst().get().getMenuItem();
+                .findFirst();
+
+        if (result.isPresent()) {
+            return result.get().getMenuItem();
+        } else {
+            return new ItemStack(Material.PLAYER_HEAD);
+        }
     }
 
     /**
@@ -78,4 +84,8 @@ public enum Category {
         return null;
     }
 
+    public static Category[] getCache() {
+        return cache;
+    }
+
 }

src/main/java/tsp/headdb/implementation/Head.java

@@ -28,7 +28,6 @@ public class Head {
     private int id;
     private List<String> tags;
     private ItemStack menuItem;
-    //Unimplemented private ItemStack itemStack;
 
     public Head() {}
 
@@ -55,7 +54,7 @@ public class Head {
                 profileField.set(meta, profile);
             } catch (NoSuchFieldException | IllegalArgumentException | IllegalAccessException ex) {
                 Log.error("Could not set skull owner for " + uuid.toString() + " | Stack Trace:");
-                ex.printStackTrace();
+                Log.error(ex);
             }
 
             meta.setLore(Arrays.asList(
@@ -72,24 +71,6 @@ public class Head {
         return menuItem;
     }
 
-    /* For some reason this causes issues with some heads in categories not having lore
-    public ItemStack getItemStack() {
-        if (itemStack == null) {
-            itemStack = menuItem;
-            ItemMeta meta = itemStack.getItemMeta();
-            meta.setDisplayName(HeadDB.getInstance().getLocalization().getMessage("head.name")
-                    .replace("%name%", name)
-                    .replace("%id%", String.valueOf(id))
-                    .replace("%value%", value)
-                    .replace("%tags%", buildTagLore(tags)));
-            meta.setLore(HeadDB.getInstance().getLocalization().getData().getStringList("head.lore"));
-            itemStack.setItemMeta(meta);
-        }
-
-        return itemStack;
-    }
-    */
-
     public String getName() {
         return name;
     }

src/main/java/tsp/headdb/implementation/HeadDatabase.java

@@ -19,6 +19,7 @@ import java.net.URL;
 import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.EnumMap;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
@@ -36,7 +37,7 @@ import javax.annotation.Nonnull;
 public class HeadDatabase {
 
     private final JavaPlugin plugin;
-    private final Map<Category, List<Head>> HEADS = new HashMap<>();
+    private final EnumMap<Category, List<Head>> heads = new EnumMap<>(Category.class);
     private long refresh;
     private int timeout;
     private long updated;
@@ -49,8 +50,8 @@ public class HeadDatabase {
     }
 
     public Head getHeadByValue(String value) {
-        List<Head> heads = getHeads();
+        List<Head> fetched = getHeads();
-        for (Head head : heads) {
+        for (Head head : fetched) {
             if (head.getValue().equals(value)) {
                 return head;
             }
@@ -60,8 +61,8 @@ public class HeadDatabase {
     }
 
     public Head getHeadByID(int id) {
-        List<Head> heads = getHeads();
+        List<Head> fetched = getHeads();
-        for (Head head : heads) {
+        for (Head head : fetched) {
             if (head.getId() == id) {
                 return head;
             }
@@ -71,8 +72,8 @@ public class HeadDatabase {
     }
 
     public Head getHeadByUniqueId(UUID uuid) {
-        List<Head> heads = getHeads();
+        List<Head> fetched = getHeads();
-        for (Head head : heads) {
+        for (Head head : fetched) {
             if (head.getUniqueId().equals(uuid)) {
                 return head;
             }
@@ -83,9 +84,9 @@ public class HeadDatabase {
 
     public List<Head> getHeadsByTag(String tag) {
         List<Head> result = new ArrayList<>();
-        List<Head> heads = getHeads();
+        List<Head> fetched = getHeads();
         tag = tag.toLowerCase(Locale.ROOT);
-        for (Head head : heads) {
+        for (Head head : fetched) {
             for (String t : head.getTags()) {
                 if (t.toLowerCase(Locale.ROOT).contains(tag)) {
                     result.add(head);
@@ -98,8 +99,8 @@ public class HeadDatabase {
 
     public List<Head> getHeadsByName(Category category, String name) {
         List<Head> result = new ArrayList<>();
-        List<Head> heads = getHeads(category);
+        List<Head> fetched = getHeads(category);
-        for (Head head : heads) {
+        for (Head head : fetched) {
             String hName = ChatColor.stripColor(head.getName().toLowerCase(Locale.ROOT));
             if (hName.contains(ChatColor.stripColor(name.toLowerCase(Locale.ROOT)))) {
                 result.add(head);
@@ -111,7 +112,7 @@ public class HeadDatabase {
 
     public List<Head> getHeadsByName(String name) {
         List<Head> result = new ArrayList<>();
-        for (Category category : Category.values()) {
+        for (Category category : Category.getCache()) {
             result.addAll(getHeadsByName(category, name));
         }
 
@@ -120,7 +121,7 @@ public class HeadDatabase {
 
     @Nonnull
     public List<Head> getHeads(Category category) {
-        return HEADS.get(category) != null ? Collections.unmodifiableList(HEADS.get(category)) : new ArrayList<>();
+        return heads.get(category) != null ? Collections.unmodifiableList(heads.get(category)) : new ArrayList<>();
     }
 
     /**
@@ -130,18 +131,18 @@ public class HeadDatabase {
      */
     @Nonnull
     public List<Head> getHeads() {
-        List<Head> heads = new ArrayList<>();
+        List<Head> result = new ArrayList<>();
-        for (Category category : HEADS.keySet()) {
+        for (Category category : heads.keySet()) {
-            heads.addAll(getHeads(category));
+            result.addAll(getHeads(category));
         }
-        return heads;
+        return result;
     }
 
     public void getHeadsNoCache(Consumer<Map<Category, List<Head>>> resultSet) {
         Bukkit.getScheduler().runTaskAsynchronously(plugin, task -> {
             Log.debug("[" + plugin.getName() + "] Updating database... ");
-            Map<Category, List<Head>> result = new HashMap<>();
+            EnumMap<Category, List<Head>> result = new EnumMap<>(Category.class);
-            Category[] categories = Category.cache;
+            Category[] categories = Category.getCache();
 
             for (Category category : categories) {
                 Log.debug("Caching heads from: " + category.getName());
@@ -160,7 +161,7 @@ public class HeadDatabase {
                             heads = gather("https://heads.pages.dev/archive/" + category.getName() + ".json", category);
                         } catch (IOException | ParseException ex) {
                             Log.error("Failed to fetch heads for " + category.getName() + "! (OF)"); // OF = Original-Fallback, both failed
-                            ex.printStackTrace();
+                            Log.error(ex);
                         }
                     }
                 }
@@ -185,7 +186,7 @@ public class HeadDatabase {
      */
     private List<Head> gather(String url, Category category) throws IOException, ParseException {
         long start = System.currentTimeMillis();
-        List<Head> heads = new ArrayList<>();
+        List<Head> headList = new ArrayList<>();
         JSONParser parser = new JSONParser();
         JSONArray array = (JSONArray) parser.parse(fetch(url));
         for (Object o : array) {
@@ -207,12 +208,12 @@ public class HeadDatabase {
                     .category(category);
 
             nextId++;
-            heads.add(head);
+            headList.add(head);
         }
 
         long elapsed = (System.currentTimeMillis() - start);
         Log.debug(category.getName() + " -> Done! Time: " + elapsed + "ms (" + TimeUnit.MILLISECONDS.toSeconds(elapsed) + "s)");
-        return heads;
+        return headList;
     }
 
     /**
@@ -239,15 +240,15 @@ public class HeadDatabase {
     }
 
     public void update(Consumer<Map<Category, List<Head>>> result) {
-        Bukkit.getScheduler().runTaskAsynchronously(plugin, task -> getHeadsNoCache(heads -> {
+        Bukkit.getScheduler().runTaskAsynchronously(plugin, task -> getHeadsNoCache(headsList -> {
-            if (heads == null) {
+            if (headsList == null) {
                 Log.error("[" + plugin.getName() + "] Failed to update database! Check above for any errors.");
                 result.accept(null);
                 return;
             }
 
-            HEADS.clear();
+            heads.clear();
-            HEADS.putAll(heads);
+            heads.putAll(headsList);
             result.accept(heads);
             Bukkit.getPluginManager().callEvent(new DatabaseUpdateEvent(this, heads));
         }));

src/main/java/tsp/headdb/implementation/LocalHead.java

@@ -8,6 +8,7 @@ import org.bukkit.inventory.meta.SkullMeta;
 import tsp.headdb.util.Utils;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.UUID;
 
@@ -68,7 +69,7 @@ public class LocalHead extends Head {
 
     @Override
     public List<String> getTags() {
-        return null;
+        return Collections.emptyList();
     }
 
     @Override

src/main/java/tsp/headdb/inventory/Button.java

@@ -11,10 +11,10 @@ import java.util.function.Consumer;
  */
 public class Button {
 
-    private static int counter;
+    private static int counter = 0;
-    private final int ID = counter++;
+    private static final int id = counter++;
 
-    private ItemStack itemStack;
+    private final ItemStack itemStack;
     private Consumer<InventoryClickEvent> action;
 
     /**
@@ -67,15 +67,14 @@ public class Button {
         if (this == o) {
             return true;
         }
-        if (!(o instanceof Button)) {
+        if (!(o instanceof Button button)) {
             return false;
         }
-        Button button = (Button) o;
+        return id == button.id;
-        return ID == button.ID;
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(ID);
+        return Objects.hash(id);
     }
 }

src/main/java/tsp/headdb/inventory/InventoryUtils.java

@@ -31,6 +31,8 @@ import java.util.function.Consumer;
  */
 public class InventoryUtils {
 
+    private InventoryUtils() {}
+
     private static final Localization localization = HeadDB.getInstance().getLocalization();
     private static final Map<String, Integer> uiLocation = new HashMap<>();
     private static final Map<String, ItemStack> uiItem = new HashMap<>();
@@ -179,7 +181,7 @@ public class InventoryUtils {
         Inventory inventory = Bukkit.createInventory(null, 54,
                 replace(localization.getMessage("menu.main"), HeadAPI.getHeads().size(), "Main", "None", player));
 
-        for (Category category : Category.cache) {
+        for (Category category : Category.getCache()) {
             ItemStack item = getUIItem(category.getName(), category.getItem());
             ItemMeta meta = item.getItemMeta();
             meta.setDisplayName(Utils.colorize(localization.getMessage("menu.heads." + category.getName())));
@@ -325,9 +327,9 @@ public class InventoryUtils {
             // If the cost is higher than zero, attempt to charge for it.
             if (cost.compareTo(BigDecimal.ZERO) > 0) {
                 economyProvider.canPurchase(player, cost, paymentResult -> {
-                    if (paymentResult) {
+                    if (Boolean.TRUE.equals(paymentResult)) {
                         economyProvider.charge(player, cost, chargeResult -> {
-                            if (chargeResult) {
+                            if (Boolean.TRUE.equals(chargeResult)) {
                                 Utils.sendMessage(player, String.format(localization.getMessage("purchasedHead"), amount, description, cost));
                                 Utils.playSound(player, "paid");
                                 result.accept(true);
@@ -353,7 +355,7 @@ public class InventoryUtils {
     public static void purchaseHead(Player player, Head head, int amount, String category, String description) {
         Utils.sendMessage(player, String.format(localization.getMessage("processPayment"), amount, head.getName()));
         processPayment(player, amount, category, description, result -> {
-            if (result) {
+            if (Boolean.TRUE.equals(result)) {
                 PlayerHeadPurchaseEvent event = new PlayerHeadPurchaseEvent(player, head, getCategoryCost(player, category));
                 Bukkit.getPluginManager().callEvent(event);
                 if (!event.isCancelled()) {

src/main/java/tsp/headdb/inventory/PagedPane.java

@@ -241,7 +241,6 @@ public class PagedPane implements InventoryHolder {
             inventory.setItem(inventory.getSize() - 2, itemStack);
         }
 
-        {
         String name = String.format(
                 Locale.ROOT,
                 "&3&lPage &a&l%d &7/ &c&l%d",
@@ -278,7 +277,6 @@ public class PagedPane implements InventoryHolder {
         });
         inventory.setItem(inventory.getSize() - 5, itemStack);
     }
-    }
 
     private void fillRow(int rowIndex, ItemStack itemStack, Inventory inventory) {
         int yMod = rowIndex * 9;
@@ -291,29 +289,11 @@ public class PagedPane implements InventoryHolder {
     protected ItemStack setMeta(ItemStack itemStack, String name, String... lore) {
         ItemMeta meta = itemStack.getItemMeta();
         meta.setDisplayName(Utils.colorize(name));
-        meta.setLore(Arrays.stream(lore).map(this::color).collect(Collectors.toList()));
+        meta.setLore(Arrays.stream(lore).map(this::color).toList());
         itemStack.setItemMeta(meta);
         return itemStack;
     }
 
-    @SuppressWarnings("WeakerAccess")
-    @Deprecated
-    protected ItemStack getItemStack(Material type, int durability, String name, String... lore) {
-        ItemStack itemStack = new ItemStack(type, 1, (short) durability);
-
-        ItemMeta itemMeta = itemStack.getItemMeta();
-
-        if (name != null) {
-            itemMeta.setDisplayName(color(name));
-        }
-        if (lore != null && lore.length != 0) {
-            itemMeta.setLore(Arrays.stream(lore).map(this::color).collect(Collectors.toList()));
-        }
-        itemStack.setItemMeta(itemMeta);
-
-        return itemStack;
-    }
-
     @SuppressWarnings("WeakerAccess")
     protected String color(String input) {
         return ChatColor.translateAlternateColorCodes('&', input);

src/main/java/tsp/headdb/listener/PagedPaneListener.java

@@ -20,8 +20,8 @@ public class PagedPaneListener implements Listener {
     public void onClick(InventoryClickEvent event) {
         InventoryHolder holder = event.getInventory().getHolder();
 
-        if (holder instanceof PagedPane) {
+        if (holder instanceof PagedPane pane) {
-            ((PagedPane) holder).onClick(event);
+            pane.onClick(event);
         }
     }
 }

src/main/java/tsp/headdb/storage/PlayerDataFile.java

@@ -30,11 +30,11 @@ public class PlayerDataFile {
     public PlayerDataFile(String name) {
         HeadDB plugin = HeadDB.getInstance();
         // This check avoids warning in console
-        if (plugin.getResource(name) != null && !new File(plugin.getDataFolder() + "/" + name).exists()) {
+        if (plugin.getResource(name) != null && !new File(plugin.getDataFolder(), name).exists()) {
             plugin.saveResource(name, false);
         }
 
-        this.file = new File(plugin.getDataFolder() + "/" + name);
+        this.file = new File(plugin.getDataFolder(), name);
     }
 
     @Nonnull
@@ -127,15 +127,12 @@ public class PlayerDataFile {
             return;
         }
 
-        FileWriter writer;
+        try (FileWriter writer = new FileWriter(file)) {
-        try {
-            writer = new FileWriter(file);
             writer.write(main.toString());
-            writer.close();
             Log.debug("Saved data to " + file.getName());
-        } catch (IOException e) {
+        } catch (IOException ex) {
             Log.error("Failed to save player_data.json contents!");
-            Log.error(e);
+            Log.error(ex);
         }
     }
 

src/main/java/tsp/headdb/util/Utils.java

@@ -21,7 +21,9 @@ import java.util.regex.Pattern;
 /**
  * Several utilities used by the plugin
  */
-public class Utils {
+public final class Utils {
+
+    private Utils() {}
 
     private static final FileConfiguration config = HeadDB.getInstance().getConfig();
     public static final Pattern UUID_PATTERN = Pattern.compile("[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}");
@@ -45,9 +47,9 @@ public class Utils {
                 connection.setRequestProperty("User-Agent", plugin.getName() + "-VersionChecker");
 
                 latest.accept(new BufferedReader(new InputStreamReader(connection.getInputStream())).readLine().equals(plugin.getDescription().getVersion()));
-            } catch (IOException e) {
+            } catch (IOException ex) {
                 latest.accept(true); // Assume the version is latest if checking fails
-                e.printStackTrace();
+                Log.error(ex);
             }
         });
     }