Don't set default locale, instead use Locale.ENGLISH where possible

src/main/java/me/libraryaddict/disguise/DisguiseConfig.java

@@ -692,14 +692,14 @@ public class DisguiseConfig {
         }
 
         try {
-            setPlayerNameType(PlayerNameType.valueOf(config.getString("PlayerNames").toUpperCase()));
+            setPlayerNameType(PlayerNameType.valueOf(config.getString("PlayerNames").toUpperCase(Locale.ENGLISH)));
         } catch (Exception ex) {
             DisguiseUtilities.getLogger().warning(
                     "Cannot parse '" + config.getString("PlayerNames") + "' to a valid option for PlayerNames");
         }
 
         try {
-            setNotifyBar(NotifyBar.valueOf(config.getString("NotifyBar").toUpperCase()));
+            setNotifyBar(NotifyBar.valueOf(config.getString("NotifyBar").toUpperCase(Locale.ENGLISH)));
 
             if (getNotifyBar() == NotifyBar.BOSS_BAR && !NmsVersion.v1_13.isSupported()) {
                 DisguiseUtilities.getLogger().warning(
@@ -714,21 +714,21 @@ public class DisguiseConfig {
         }
 
         try {
-            setBossBarColor(BarColor.valueOf(config.getString("BossBarColor").toUpperCase()));
+            setBossBarColor(BarColor.valueOf(config.getString("BossBarColor").toUpperCase(Locale.ENGLISH)));
         } catch (Exception ex) {
             DisguiseUtilities.getLogger().warning(
                     "Cannot parse '" + config.getString("BossBarColor") + "' to a valid option for BossBarColor");
         }
 
         try {
-            setBossBarStyle(BarStyle.valueOf(config.getString("BossBarStyle").toUpperCase()));
+            setBossBarStyle(BarStyle.valueOf(config.getString("BossBarStyle").toUpperCase(Locale.ENGLISH)));
         } catch (Exception ex) {
             DisguiseUtilities.getLogger().warning(
                     "Cannot parse '" + config.getString("BossBarStyle") + "' to a valid option for BossBarStyle");
         }
 
         try {
-            setUpdatesBranch(UpdatesBranch.valueOf(config.getString("UpdatesBranch").toUpperCase()));
+            setUpdatesBranch(UpdatesBranch.valueOf(config.getString("UpdatesBranch").toUpperCase(Locale.ENGLISH)));
         } catch (Exception ex) {
             DisguiseUtilities.getLogger().warning(
                     "Cannot parse '" + config.getString("UpdatesBranch") + "' to a valid option for UpdatesBranch");
@@ -736,7 +736,7 @@ public class DisguiseConfig {
 
         try {
             String option =
-                    config.getString("SelfDisguisesScoreboard", DisguisePushing.MODIFY_SCOREBOARD.name()).toUpperCase();
+                    config.getString("SelfDisguisesScoreboard", DisguisePushing.MODIFY_SCOREBOARD.name()).toUpperCase(Locale.ENGLISH);
 
             if (!option.endsWith("_SCOREBOARD")) {
                 option += "_SCOREBOARD";

src/main/java/me/libraryaddict/disguise/commands/DisguiseBaseCommand.java

@@ -194,12 +194,12 @@ public abstract class DisguiseBaseCommand implements CommandExecutor {
             return list;
 
         Iterator<String> itel = list.iterator();
-        String label = origArgs[origArgs.length - 1].toLowerCase();
+        String label = origArgs[origArgs.length - 1].toLowerCase(Locale.ENGLISH);
 
         while (itel.hasNext()) {
             String name = itel.next();
 
-            if (name.toLowerCase().startsWith(label))
+            if (name.toLowerCase(Locale.ENGLISH).startsWith(label))
                 continue;
 
             itel.remove();

src/main/java/me/libraryaddict/disguise/commands/LibsDisguisesCommand.java

@@ -14,6 +14,7 @@ import org.bukkit.command.TabCompleter;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Locale;
 
 public class LibsDisguisesCommand implements CommandExecutor, TabCompleter {
     @Getter
@@ -41,12 +42,12 @@ public class LibsDisguisesCommand implements CommandExecutor, TabCompleter {
             return list;
 
         Iterator<String> itel = list.iterator();
-        String label = origArgs[origArgs.length - 1].toLowerCase();
+        String label = origArgs[origArgs.length - 1].toLowerCase(Locale.ENGLISH);
 
         while (itel.hasNext()) {
             String name = itel.next();
 
-            if (name.toLowerCase().startsWith(label))
+            if (name.toLowerCase(Locale.ENGLISH).startsWith(label))
                 continue;
 
             itel.remove();
@@ -104,7 +105,7 @@ public class LibsDisguisesCommand implements CommandExecutor, TabCompleter {
             LDCommand command = null;
 
             for (LDCommand c : getCommands()) {
-                if (!c.getTabComplete().contains(args[0].toLowerCase())) {
+                if (!c.getTabComplete().contains(args[0].toLowerCase(Locale.ENGLISH))) {
                     continue;
                 }
 

src/main/java/me/libraryaddict/disguise/commands/disguise/DisguiseRadiusCommand.java

@@ -26,6 +26,7 @@ import org.bukkit.entity.Player;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 
 public class DisguiseRadiusCommand extends DisguiseBaseCommand implements TabCompleter {
     private int maxRadius = 30;
@@ -98,7 +99,7 @@ public class DisguiseRadiusCommand extends DisguiseBaseCommand implements TabCom
 
             if (starting == 0) {
                 try {
-                    type = EntityType.valueOf(args[0].toUpperCase());
+                    type = EntityType.valueOf(args[0].toUpperCase(Locale.ENGLISH));
                 }
                 catch (Exception ignored) {
                 }

src/main/java/me/libraryaddict/disguise/commands/undisguise/UndisguisePlayerCommand.java

@@ -13,10 +13,7 @@ import org.bukkit.command.TabCompleter;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Player;
 
-import java.util.ArrayList;
+import java.util.*;
-import java.util.Iterator;
-import java.util.List;
-import java.util.UUID;
 
 public class UndisguisePlayerCommand implements CommandExecutor, TabCompleter {
     protected ArrayList<String> filterTabs(ArrayList<String> list, String[] origArgs) {
@@ -24,12 +21,12 @@ public class UndisguisePlayerCommand implements CommandExecutor, TabCompleter {
             return list;
 
         Iterator<String> itel = list.iterator();
-        String label = origArgs[origArgs.length - 1].toLowerCase();
+        String label = origArgs[origArgs.length - 1].toLowerCase(Locale.ENGLISH);
 
         while (itel.hasNext()) {
             String name = itel.next();
 
-            if (name.toLowerCase().startsWith(label))
+            if (name.toLowerCase(Locale.ENGLISH).startsWith(label))
                 continue;
 
             itel.remove();

src/main/java/me/libraryaddict/disguise/commands/utils/DisguiseHelpCommand.java

@@ -18,6 +18,7 @@ import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 
 public class DisguiseHelpCommand extends DisguiseBaseCommand implements TabCompleter {
 
@@ -80,7 +81,8 @@ public class DisguiseHelpCommand extends DisguiseBaseCommand implements TabCompl
                 try {
                     for (Method method : ParamInfoManager.getDisguiseWatcherMethods(watcher)) {
                         if (args.length < 2 || !args[1].equalsIgnoreCase(LibsMsg.DHELP_SHOW.get())) {
-                            if (!perms.isAllowedDisguise(type, Collections.singleton(method.getName().toLowerCase()))) {
+                            if (!perms.isAllowedDisguise(type, Collections.singleton(method.getName().toLowerCase(
+                                    Locale.ENGLISH)))) {
                                 ignored++;
                                 continue;
                             }

src/main/java/me/libraryaddict/disguise/disguisetypes/DisguiseType.java

@@ -8,6 +8,8 @@ import org.apache.commons.lang.StringUtils;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 
+import java.util.Locale;
+
 public enum DisguiseType {
     AREA_EFFECT_CLOUD(3, 0),
 
@@ -364,7 +366,7 @@ public enum DisguiseType {
         String[] split = name().split("_");
 
         for (int i = 0; i < split.length; i++) {
-            split[i] = split[i].substring(0, 1) + split[i].substring(1).toLowerCase();
+            split[i] = split[i].charAt(0) + split[i].substring(1).toLowerCase(Locale.ENGLISH);
         }
 
         return TranslateType.DISGUISES.get(StringUtils.join(split, " "));

src/main/java/me/libraryaddict/disguise/disguisetypes/MetaIndex.java

@@ -855,7 +855,7 @@ public class MetaIndex<Y> {
     }
 
     public static MetaIndex getMetaIndexByName(String name) {
-        name = name.toUpperCase();
+        name = name.toUpperCase(Locale.ENGLISH);
 
         try {
             for (Field field : MetaIndex.class.getFields()) {

src/main/java/me/libraryaddict/disguise/disguisetypes/watchers/MushroomCowWatcher.java

@@ -6,6 +6,8 @@ import me.libraryaddict.disguise.utilities.reflection.NmsAddedIn;
 import me.libraryaddict.disguise.utilities.reflection.NmsVersion;
 import org.bukkit.entity.MushroomCow;
 
+import java.util.Locale;
+
 /**
  * Created by libraryaddict on 6/05/2019.
  */
@@ -16,12 +18,12 @@ public class MushroomCowWatcher extends AgeableWatcher {
 
     @NmsAddedIn(NmsVersion.v1_14)
     public MushroomCow.Variant getVariant() {
-        return MushroomCow.Variant.valueOf(getData(MetaIndex.MUSHROOM_COW_TYPE).toUpperCase());
+        return MushroomCow.Variant.valueOf(getData(MetaIndex.MUSHROOM_COW_TYPE).toUpperCase(Locale.ENGLISH));
     }
 
     @NmsAddedIn(NmsVersion.v1_14)
     public void setVariant(MushroomCow.Variant variant) {
-        setData(MetaIndex.MUSHROOM_COW_TYPE, variant.name().toLowerCase());
+        setData(MetaIndex.MUSHROOM_COW_TYPE, variant.name().toLowerCase(Locale.ENGLISH));
         sendData(MetaIndex.MUSHROOM_COW_TYPE);
     }
 }

src/main/java/me/libraryaddict/disguise/utilities/DisguiseUtilities.java

@@ -410,7 +410,7 @@ public class DisguiseUtilities {
     }
 
     public static boolean hasGameProfile(String playername) {
-        return cachedNames.contains(playername.toLowerCase());
+        return cachedNames.contains(playername.toLowerCase(Locale.ENGLISH));
     }
 
     public static void createClonedDisguise(Player player, Entity toClone, Boolean[] options) {
@@ -674,12 +674,12 @@ public class DisguiseUtilities {
                 profileCache.mkdirs();
             }
 
-            File file = new File(profileCache, string.toLowerCase());
+            File file = new File(profileCache, string.toLowerCase(Locale.ENGLISH));
             PrintWriter writer = new PrintWriter(file);
             writer.write(gson.toJson(gameProfile));
             writer.close();
 
-            cachedNames.add(string.toLowerCase());
+            cachedNames.add(string.toLowerCase(Locale.ENGLISH));
         } catch (StackOverflowError | Exception e) {
             e.printStackTrace();
         }
@@ -888,7 +888,7 @@ public class DisguiseUtilities {
     }
 
     public static WrappedGameProfile getGameProfile(String playerName) {
-        playerName = playerName.toLowerCase();
+        playerName = playerName.toLowerCase(Locale.ENGLISH);
 
         if (!hasGameProfile(playerName)) {
             return null;
@@ -914,7 +914,7 @@ public class DisguiseUtilities {
         } catch (JsonSyntaxException ex) {
             DisguiseUtilities.getLogger()
                     .warning("Gameprofile " + file.getName() + " had invalid gson and has been deleted");
-            cachedNames.remove(playerName.toLowerCase());
+            cachedNames.remove(playerName);
             file.delete();
         } catch (Exception e) {
             e.printStackTrace();
@@ -1019,7 +1019,7 @@ public class DisguiseUtilities {
 
     private static WrappedGameProfile getProfileFromMojang(final String origName, final Object runnable,
                                                            boolean contactMojang) {
-        final String playerName = origName.toLowerCase();
+        final String playerName = origName.toLowerCase(Locale.ENGLISH);
 
         if (DisguiseConfig.isSaveGameProfiles() && hasGameProfile(playerName)) {
             WrappedGameProfile profile = getGameProfile(playerName);
@@ -1153,7 +1153,7 @@ public class DisguiseUtilities {
         cachedNames.addAll(Arrays.asList(profileCache.list()));
 
         invalidFile =
-                LibsDisguises.getInstance().getFile().getName().toLowerCase().matches(".*((crack)|(null)|(leak)).*");
+                LibsDisguises.getInstance().getFile().getName().toLowerCase(Locale.ENGLISH).matches(".*((crack)|(null)|(leak)).*");
 
         for (String key : savedDisguises.list()) {
             try {
@@ -1457,13 +1457,13 @@ public class DisguiseUtilities {
     }
 
     public static void removeGameProfile(String string) {
-        cachedNames.remove(string.toLowerCase());
+        cachedNames.remove(string.toLowerCase(Locale.ENGLISH));
 
         if (!profileCache.exists()) {
             profileCache.mkdirs();
         }
 
-        File file = new File(profileCache, string.toLowerCase());
+        File file = new File(profileCache, string.toLowerCase(Locale.ENGLISH));
 
         file.delete();
     }

src/main/java/me/libraryaddict/disguise/utilities/SkinUtils.java

@@ -10,6 +10,7 @@ import me.libraryaddict.disguise.utilities.translations.LibsMsg;
 import org.bukkit.scheduler.BukkitRunnable;
 
 import java.io.File;
+import java.util.Locale;
 import java.util.UUID;
 import java.util.regex.Pattern;
 
@@ -165,7 +166,7 @@ public class SkinUtils {
     }
 
     public static void grabSkin(String param, SkinCallback callback) {
-        ModelType modelType = param.toLowerCase().endsWith(":slim") ? ModelType.SLIM : ModelType.NORMAL;
+        ModelType modelType = param.toLowerCase(Locale.ENGLISH).endsWith(":slim") ? ModelType.SLIM : ModelType.NORMAL;
 
         if (modelType == ModelType.SLIM) {
             param = param.substring(0, param.length() - ":slim".length());
@@ -184,12 +185,12 @@ public class SkinUtils {
             }
 
             File file = new File(LibsDisguises.getInstance().getDataFolder(),
-                    "/Skins/" + param + (param.toLowerCase().endsWith(".png") ? "" : ".png"));
+                    "/Skins/" + param + (param.toLowerCase(Locale.ENGLISH).endsWith(".png") ? "" : ".png"));
 
             if (!file.exists()) {
                 file = null;
 
-                if (param.toLowerCase().endsWith(".png")) {
+                if (param.toLowerCase(Locale.ENGLISH).endsWith(".png")) {
                     callback.onError(LibsMsg.SKIN_API_BAD_FILE_NAME);
                     return;
                 }

src/main/java/me/libraryaddict/disguise/utilities/modded/ModdedManager.java

@@ -22,6 +22,7 @@ import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.Locale;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
@@ -185,7 +186,7 @@ public class ModdedManager {
                 continue;
             }
 
-            if (mods.contains(e.getMod().toLowerCase())) {
+            if (mods.contains(e.getMod().toLowerCase(Locale.ENGLISH))) {
                 continue;
             }
 

src/main/java/me/libraryaddict/disguise/utilities/params/ParamInfoManager.java

@@ -21,6 +21,7 @@ import javax.annotation.Nullable;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Locale;
 
 public class ParamInfoManager {
     private static List<ParamInfo> paramList;
@@ -79,7 +80,7 @@ public class ParamInfoManager {
 
     public static ParamInfo getParamInfo(DisguiseType disguiseType, String methodName) {
         for (Method method : getDisguiseWatcherMethods(disguiseType.getWatcherClass())) {
-            if (!method.getName().toLowerCase().equals(methodName.toLowerCase()))
+            if (!method.getName().toLowerCase(Locale.ENGLISH).equals(methodName.toLowerCase(Locale.ENGLISH)))
                 continue;
 
             return getParamInfo(method);

src/main/java/me/libraryaddict/disguise/utilities/params/ParamInfoTypes.java

@@ -207,7 +207,7 @@ public class ParamInfoTypes {
         String[] split = string.split("_");
 
         for (int i = 0; i < split.length; i++) {
-            split[i] = split[i].substring(0, 1) + split[i].substring(1).toLowerCase();
+            split[i] = split[i].substring(0, 1) + split[i].substring(1).toLowerCase(Locale.ENGLISH);
         }
 
         return StringUtils.join(split, "_");

src/main/java/me/libraryaddict/disguise/utilities/params/types/custom/ParamInfoBlockData.java

@@ -9,6 +9,7 @@ import org.bukkit.block.data.BlockData;
 
 import java.util.Arrays;
 import java.util.HashSet;
+import java.util.Locale;
 import java.util.Set;
 
 /**
@@ -72,7 +73,7 @@ public class ParamInfoBlockData extends ParamInfo {
 
     @Override
     public Set<String> getEnums(String tabComplete) {
-        String s = tabComplete.toLowerCase();
+        String s = tabComplete.toLowerCase(Locale.ENGLISH);
         HashSet<String> returns = new HashSet<>();
 
         if (s.matches("[a-z_:]+\\[.*")) {
@@ -83,11 +84,11 @@ public class ParamInfoBlockData extends ParamInfo {
                     continue;
                 }
 
-                if (!m.name().toLowerCase().startsWith(s) && !m.getKey().toString().startsWith(s)) {
+                if (!m.name().toLowerCase(Locale.ENGLISH).startsWith(s) && !m.getKey().toString().startsWith(s)) {
                     continue;
                 }
 
-                if (m.name().toLowerCase().startsWith(s)) {
+                if (m.name().toLowerCase(Locale.ENGLISH).startsWith(s)) {
                     returns.add(m.name());
                 } else {
                     returns.add(m.getKey().toString());

src/main/java/me/libraryaddict/disguise/utilities/params/types/custom/ParamInfoItemBlock.java

@@ -6,6 +6,7 @@ import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 
 import java.util.Arrays;
+import java.util.Locale;
 
 /**
  * Created by libraryaddict on 16/02/2020.
@@ -48,10 +49,10 @@ public class ParamInfoItemBlock extends ParamInfoItemStack {
             throw new IllegalArgumentException();
         }
 
-        Material material = ReflectionManager.getMaterial(split[0].toLowerCase());
+        Material material = ReflectionManager.getMaterial(split[0].toLowerCase(Locale.ENGLISH));
 
         if (material == null || material == Material.AIR) {
-            material = Material.getMaterial(split[0].toUpperCase());
+            material = Material.getMaterial(split[0].toUpperCase(Locale.ENGLISH));
         }
 
         if (material == null || (material == Material.AIR && !split[0].equalsIgnoreCase("air"))) {

src/main/java/me/libraryaddict/disguise/utilities/params/types/custom/ParamInfoItemStack.java

@@ -15,6 +15,7 @@ import org.bukkit.inventory.ItemStack;
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Locale;
 
 /**
  * Created by libraryaddict on 7/09/2018.
@@ -130,10 +131,10 @@ public class ParamInfoItemStack extends ParamInfoEnum {
                 split = string.split("[ -]");
             }
 
-            Material material = ReflectionManager.getMaterial(split[0].toLowerCase());
+            Material material = ReflectionManager.getMaterial(split[0].toLowerCase(Locale.ENGLISH));
 
             if (material == null) {
-                material = Material.getMaterial(split[0].toUpperCase());
+                material = Material.getMaterial(split[0].toUpperCase(Locale.ENGLISH));
             }
 
             if (material == null || (material == Material.AIR && !split[0].equalsIgnoreCase("air"))) {
@@ -164,7 +165,7 @@ public class ParamInfoItemStack extends ParamInfoEnum {
             return null;
         }
 
-        Material material = Material.getMaterial(split[0].toUpperCase());
+        Material material = Material.getMaterial(split[0].toUpperCase(Locale.ENGLISH));
 
         if (material == null || (material == Material.AIR && !split[0].equalsIgnoreCase("air"))) {
             throw new IllegalArgumentException();

src/main/java/me/libraryaddict/disguise/utilities/params/types/custom/ParamInfoItemStackArray.java

@@ -6,6 +6,7 @@ import org.bukkit.inventory.ItemStack;
 
 import java.util.ArrayList;
 import java.util.LinkedHashSet;
+import java.util.Locale;
 import java.util.Set;
 
 /**
@@ -37,7 +38,7 @@ public class ParamInfoItemStackArray extends ParamInfoItemStack {
         String lastEntry = split.remove(split.size() - 1);
 
         for (String material : super.getEnums(null)) {
-            if (!split.isEmpty() && !material.toLowerCase().startsWith(lastEntry.toLowerCase()))
+            if (!split.isEmpty() && !material.toLowerCase(Locale.ENGLISH).startsWith(lastEntry.toLowerCase(Locale.ENGLISH)))
                 continue;
 
             toReturn.add(StringUtils.join(split, ",") + (split.isEmpty() ? "" : ",") + material);

src/main/java/me/libraryaddict/disguise/utilities/params/types/custom/ParamInfoParticle.java

@@ -14,6 +14,7 @@ import org.bukkit.inventory.ItemStack;
 
 import java.util.Arrays;
 import java.util.HashSet;
+import java.util.Locale;
 import java.util.Set;
 
 /**
@@ -38,7 +39,7 @@ public class ParamInfoParticle extends ParamInfoEnum {
 
         enums = new HashSet<>(enums);
 
-        tabComplete = tabComplete.toUpperCase();
+        tabComplete = tabComplete.toUpperCase(Locale.ENGLISH);
 
         for (Particle particle : new Particle[]{Particle.BLOCK_CRACK, Particle.BLOCK_DUST, Particle.ITEM_CRACK}) {
             for (Material mat : materials) {

src/main/java/me/libraryaddict/disguise/utilities/parser/DisguiseParser.java

@@ -264,7 +264,7 @@ public class DisguiseParser {
 
         // libsdisguises.options.<command>.<disguise>.<method>.<options>
         for (PermissionAttachmentInfo permission : sender.getEffectivePermissions()) {
-            String lowerPerm = permission.getPermission().toLowerCase();
+            String lowerPerm = permission.getPermission().toLowerCase(Locale.ENGLISH);
 
             if (!lowerPerm.startsWith("libsdisguises.options.")) {
                 continue;
@@ -382,7 +382,7 @@ public class DisguiseParser {
      */
     private static boolean hasPermissionOption(HashMap<String, HashMap<String, Boolean>> disguiseOptions, String method,
                                                String value) {
-        method = method.toLowerCase();
+        method = method.toLowerCase(Locale.ENGLISH);
 
         // If no permissions were defined, return true
         if (!disguiseOptions.containsKey(method)) {
@@ -391,7 +391,7 @@ public class DisguiseParser {
 
         HashMap<String, Boolean> map = disguiseOptions.get(method);
 
-        value = value.toLowerCase();
+        value = value.toLowerCase(Locale.ENGLISH);
 
         // If they were explictly defined, can just return the value
         if (map.containsKey(value)) {
@@ -529,7 +529,7 @@ public class DisguiseParser {
     }
 
     public static long parseStringToTime(String string) throws DisguiseParseException {
-        string = string.toLowerCase();
+        string = string.toLowerCase(Locale.ENGLISH);
 
         if (!string.matches("([0-9]+[a-z]+)+")) {
             throw new DisguiseParseException(LibsMsg.PARSE_INVALID_TIME_SEQUENCE, string);
@@ -666,7 +666,7 @@ public class DisguiseParser {
 
         if (args[0].startsWith("@")) {
             if (sender.hasPermission("libsdisguises.disguise.disguiseclone")) {
-                disguise = DisguiseUtilities.getClonedDisguise(args[0].toLowerCase());
+                disguise = DisguiseUtilities.getClonedDisguise(args[0].toLowerCase(Locale.ENGLISH));
 
                 if (disguise == null) {
                     throw new DisguiseParseException(LibsMsg.PARSE_NO_REF, args[0]);
@@ -743,7 +743,7 @@ public class DisguiseParser {
                         throw new DisguiseParseException(LibsMsg.PARSE_SUPPLY_PLAYER);
                     } else {
                         // If they can't use this name, throw error
-                        if (!hasPermissionOption(disguiseOptions, "setname", args[1].toLowerCase())) {
+                        if (!hasPermissionOption(disguiseOptions, "setname", args[1].toLowerCase(Locale.ENGLISH))) {
                             if (!args[1].equalsIgnoreCase(sender.getName()) ||
                                     !hasPermissionOption(disguiseOptions, "setname", "themselves")) {
                                 throw new DisguiseParseException(LibsMsg.PARSE_NO_PERM_NAME);
@@ -829,7 +829,7 @@ public class DisguiseParser {
 
                                 usedOptions.add(optionName);
                                 doCheck(sender, permissions, disguisePerm, usedOptions);
-                                String itemName = itemStack == null ? "null" : itemStack.getType().name().toLowerCase();
+                                String itemName = itemStack == null ? "null" : itemStack.getType().name().toLowerCase(Locale.ENGLISH);
 
                                 if (!hasPermissionOption(disguiseOptions, optionName, itemName)) {
                                     throw new DisguiseParseException(LibsMsg.PARSE_NO_PERM_PARAM, itemName,
@@ -964,8 +964,8 @@ public class DisguiseParser {
                 throw new DisguiseParseException(LibsMsg.PARSE_OPTION_NA, methodNameProvided);
             }
 
-            if (!usedOptions.contains(methodToUse.getName().toLowerCase())) {
+            if (!usedOptions.contains(methodToUse.getName().toLowerCase(Locale.ENGLISH))) {
-                usedOptions.add(methodToUse.getName().toLowerCase());
+                usedOptions.add(methodToUse.getName().toLowerCase(Locale.ENGLISH));
             }
 
             doCheck(sender, disguisePermission, disguisePerm, usedOptions);

src/main/java/me/libraryaddict/disguise/utilities/parser/DisguisePermissions.java

@@ -106,7 +106,7 @@ public class DisguisePermissions {
      * @param commandName      A lowercase string consisting of the name of one of Lib's Disguises commands
      */
     public DisguisePermissions(Permissible permissionHolder, String commandName) {
-        loadPermissions(permissionHolder, commandName.toLowerCase());
+        loadPermissions(permissionHolder, commandName.toLowerCase(Locale.ENGLISH));
     }
 
     /**
@@ -197,7 +197,7 @@ public class DisguisePermissions {
         }
 
         for (PermissionAttachmentInfo permission : sender.getEffectivePermissions()) {
-            String perm = permission.getPermission().toLowerCase();
+            String perm = permission.getPermission().toLowerCase(Locale.ENGLISH);
 
             String[] split = perm.split("\\.");
 
@@ -467,14 +467,14 @@ public class DisguisePermissions {
             if (!storage.permittedOptions.isEmpty() || storage.negatedOptions.isEmpty()) {
                 // Check if they're trying to use anything they shouldn't
                 if (!disguiseOptions.stream()
-                        .allMatch(option -> storage.permittedOptions.contains(option.toLowerCase()))) {
+                        .allMatch(option -> storage.permittedOptions.contains(option.toLowerCase(Locale.ENGLISH)))) {
                     return false;
                 }
             }
         }
 
         // If the user is using a forbidden option, return false. Otherwise true
-        return disguiseOptions.stream().noneMatch(option -> storage.negatedOptions.contains(option.toLowerCase()));
+        return disguiseOptions.stream().noneMatch(option -> storage.negatedOptions.contains(option.toLowerCase(Locale.ENGLISH)));
     }
 
     public boolean isAllowedDisguise(DisguisePerm disguisePerm) {

src/main/java/me/libraryaddict/disguise/utilities/reflection/ClassGetter.java

@@ -8,6 +8,7 @@ import java.net.URLDecoder;
 import java.security.CodeSource;
 import java.util.ArrayList;
 import java.util.Enumeration;
+import java.util.Locale;
 import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
 
@@ -31,7 +32,7 @@ public class ClassGetter {
         if (src != null) {
             URL resource = src.getLocation();
 
-            if (resource.getPath().toLowerCase().endsWith(".jar")) {
+            if (resource.getPath().toLowerCase(Locale.ENGLISH).endsWith(".jar")) {
                 processJarfile(resource, pkgname, classes);
             } else {
                 for (File f : new File(resource.getPath() + "/" + pkgname.replace(".", "/")).listFiles()) {

src/main/java/me/libraryaddict/disguise/utilities/reflection/ReflectionManager.java

@@ -106,10 +106,6 @@ public class ReflectionManager {
     private static Object genericDamage;
 
     public static void init() {
-        // Sometimes it doesn't like me if I don't set this :\
-        // Weird characters in toLowerCase() for example
-        Locale.setDefault(Locale.ENGLISH);
-
         try {
             boundingBoxConstructor =
                     getNmsConstructor("AxisAlignedBB", double.class, double.class, double.class, double.class,
@@ -1373,7 +1369,7 @@ public class ReflectionManager {
     public static Object getEntityType(EntityType entityType) {
         try {
             Object val = entityTypesAMethod.invoke(null,
-                    entityType.getName() == null ? entityType.name().toLowerCase() : entityType.getName());
+                    entityType.getName() == null ? entityType.name().toLowerCase(Locale.ENGLISH) : entityType.getName());
 
             if (NmsVersion.v1_14.isSupported()) {
                 return ((Optional<Object>) val).orElse(null);
@@ -1958,7 +1954,7 @@ public class ReflectionManager {
         String[] split = string.split("_");
 
         for (int i = 0; i < split.length; i++) {
-            split[i] = split[i].charAt(0) + split[i].substring(1).toLowerCase();
+            split[i] = split[i].charAt(0) + split[i].substring(1).toLowerCase(Locale.ENGLISH);
         }
 
         return split;

src/main/java/me/libraryaddict/disguise/utilities/sounds/SoundManager.java

@@ -10,6 +10,7 @@ import org.bukkit.configuration.file.YamlConfiguration;
 import java.io.*;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
+import java.util.Locale;
 import java.util.stream.Collectors;
 
 /**
@@ -53,7 +54,7 @@ public class SoundManager {
                 }
 
                 List<String> list = section
-                        .getStringList(type.name().charAt(0) + type.name().substring(1).toLowerCase());
+                        .getStringList(type.name().charAt(0) + type.name().substring(1).toLowerCase(Locale.ENGLISH));
 
                 if (list == null || list.isEmpty()) {
                     continue;

src/main/java/me/libraryaddict/disguise/utilities/translations/TranslateFiller.java

@@ -9,6 +9,7 @@ import org.bukkit.entity.EntityType;
 
 import java.lang.reflect.Method;
 import java.util.ArrayList;
+import java.util.Locale;
 
 /**
  * Created by libraryaddict on 10/06/2017.
@@ -48,7 +49,7 @@ public class TranslateFiller {
             String[] split = type.name().split("_");
 
             for (int i = 0; i < split.length; i++) {
-                split[i] = split[i].substring(0, 1) + split[i].substring(1).toLowerCase();
+                split[i] = split[i].charAt(0) + split[i].substring(1).toLowerCase(Locale.ENGLISH);
             }
 
             TranslateType.DISGUISES.save(StringUtils.join(split, " "), "Name for the " + type.name() + " disguise");

src/main/java/me/libraryaddict/disguise/utilities/translations/TranslateType.java

@@ -10,10 +10,7 @@ import org.bukkit.configuration.file.YamlConfiguration;
 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
-import java.util.Iterator;
+import java.util.*;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.Objects;
 
 /**
  * Created by libraryaddict on 10/06/2017.
@@ -198,10 +195,10 @@ public enum TranslateType {
         if (translated == null || !LibsPremium.isPremium() || !DisguiseConfig.isUseTranslations())
             return translated;
 
-        String lowerCase = translated.toLowerCase();
+        String lowerCase = translated.toLowerCase(Locale.ENGLISH);
 
         for (Map.Entry<String, String> entry : this.translated.entrySet()) {
-            if (!Objects.equals(entry.getValue().toLowerCase(), lowerCase))
+            if (!Objects.equals(entry.getValue().toLowerCase(Locale.ENGLISH), lowerCase))
                 continue;
 
             return entry.getKey();

src/main/java/me/libraryaddict/disguise/utilities/updates/LDJenkins.java

@@ -157,7 +157,7 @@ public class LDJenkins {
 
                     changelog.add("#" + map.get("id") + ": " + ChatColor.YELLOW + msg);
 
-                    release = release || msg.toLowerCase().matches("(re)?.?release.? .*");
+                    release = release || msg.toLowerCase(Locale.ENGLISH).matches("(re)?.?release.? .*");
                 }
             }