Code smell reduction

src/main/java/world/bentobox/bentobox/api/addons/AddonDescription.java

@@ -158,7 +158,7 @@ public final class AddonDescription {
      * @return the permissions
      * @since 1.13.0
      */
-    public ConfigurationSection getPermissions() {
+    public @Nullable ConfigurationSection getPermissions() {
         return permissions;
     }
 

src/main/java/world/bentobox/bentobox/api/commands/CompositeCommand.java

@@ -218,7 +218,7 @@ public abstract class CompositeCommand extends Command implements PluginIdentifi
      * subcommands until it finds the right object and then runs execute on it.
      */
     @Override
-    public boolean execute(CommandSender sender, String label, String[] args) {
+    public boolean execute(@NonNull CommandSender sender, @NonNull String label, String[] args) {
         // Get the User instance for this sender
         User user = User.getInstance(sender);
         // Fire an event to see if this command should be cancelled
@@ -352,7 +352,7 @@ public abstract class CompositeCommand extends Command implements PluginIdentifi
     }
 
     @Override
-    public BentoBox getPlugin() {
+    public @NonNull BentoBox getPlugin() {
         return plugin;
     }
 
@@ -422,7 +422,7 @@ public abstract class CompositeCommand extends Command implements PluginIdentifi
     }
 
     @Override
-    public String getUsage() {
+    public @NonNull String getUsage() {
         return "/" + usage;
     }
 
@@ -521,7 +521,7 @@ public abstract class CompositeCommand extends Command implements PluginIdentifi
      * @return The instance of this {@link Command}.
      */
     @Override
-    public Command setDescription(String description) {
+    public @NonNull Command setDescription(@NonNull String description) {
         super.setDescription(description);
         return this;
     }
@@ -575,7 +575,7 @@ public abstract class CompositeCommand extends Command implements PluginIdentifi
      * This creates the full linking chain of commands
      */
     @Override
-    public Command setUsage(String usage) {
+    public @NonNull Command setUsage(@NonNull String usage) {
         // Go up the chain
         CompositeCommand parentCommand = getParent();
         StringBuilder u = new StringBuilder().append(getLabel()).append(" ").append(usage);
@@ -590,7 +590,7 @@ public abstract class CompositeCommand extends Command implements PluginIdentifi
 
     @Override
     @NonNull
-    public List<String> tabComplete(final CommandSender sender, final String alias, final String[] args) {
+    public List<String> tabComplete(final @NonNull CommandSender sender, final @NonNull String alias, final String[] args) {
         List<String> options = new ArrayList<>();
         // Get command object based on args entered so far
         CompositeCommand command = getCommandFromArgs(args);

src/main/java/world/bentobox/bentobox/api/commands/admin/conversations/NamePrompt.java

@@ -22,7 +22,7 @@ public class NamePrompt extends StringPrompt {
     private final String oldName;
     private final BentoBox plugin;
 
-    public NamePrompt(BentoBox plugin, @NonNull Island island, User user, String oldName) {
+    public NamePrompt(BentoBox plugin, @NonNull Island island, @NonNull User user, String oldName) {
         this.plugin = plugin;
         this.island = island;
         this.user = user;
@@ -30,12 +30,12 @@ public class NamePrompt extends StringPrompt {
     }
 
     @Override
-    public String getPromptText(ConversationContext context) {
+    public @NonNull String getPromptText(@NonNull ConversationContext context) {
         return user.getTranslation("commands.island.renamehome.enter-new-name");
     }
 
     @Override
-    public Prompt acceptInput(ConversationContext context, String input) {
+    public Prompt acceptInput(@NonNull ConversationContext context, String input) {
         if (island.renameHome(oldName, input)) {
             plugin.getIslands().save(island);
             Bukkit.getScheduler().runTask(plugin, () -> user.sendMessage("general.success"));

src/main/java/world/bentobox/bentobox/api/events/BentoBoxEvent.java

@@ -12,6 +12,7 @@ import java.util.Objects;
 import org.bukkit.event.Event;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.BentoBox;
 
 /**
@@ -55,7 +56,7 @@ public abstract class BentoBoxEvent extends Event {
      */
     @Override
     @Deprecated
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/BentoBoxReadyEvent.java

@@ -1,6 +1,7 @@
 package world.bentobox.bentobox.api.events;
 
 import org.bukkit.event.HandlerList;
+import org.eclipse.jdt.annotation.NonNull;
 
 /**
  * Fired when plugin is ready to play and all files are loaded
@@ -12,7 +13,7 @@ public class BentoBoxReadyEvent extends BentoBoxEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/OfflineMessageEvent.java

@@ -3,6 +3,7 @@ package world.bentobox.bentobox.api.events;
 import java.util.UUID;
 
 import org.bukkit.event.HandlerList;
+import org.eclipse.jdt.annotation.NonNull;
 
 /**
  * Fired when a message is going to an offline player
@@ -16,7 +17,7 @@ public class OfflineMessageEvent extends BentoBoxEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/addon/AddonDisableEvent.java

@@ -4,6 +4,7 @@ import java.util.Map;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.addons.Addon;
 
 /**
@@ -16,7 +17,7 @@ public class AddonDisableEvent extends AddonBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/addon/AddonEnableEvent.java

@@ -4,6 +4,7 @@ import java.util.Map;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.addons.Addon;
 
 /**
@@ -16,7 +17,7 @@ public class AddonEnableEvent extends AddonBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/addon/AddonGeneralEvent.java

@@ -4,6 +4,7 @@ import java.util.Map;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.addons.Addon;
 
 /**
@@ -16,7 +17,7 @@ public class AddonGeneralEvent extends AddonBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/addon/AddonLoadEvent.java

@@ -4,6 +4,7 @@ import java.util.Map;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.addons.Addon;
 
 /**
@@ -16,7 +17,7 @@ public class AddonLoadEvent extends AddonBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/command/CommandEvent.java

@@ -6,6 +6,7 @@ import org.bukkit.command.CommandSender;
 import org.bukkit.event.Cancellable;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.BentoBoxEvent;
 
 /**
@@ -24,7 +25,7 @@ public class CommandEvent extends BentoBoxEvent implements Cancellable {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/flags/FlagProtectionChangeEvent.java

@@ -4,6 +4,7 @@ import java.util.UUID;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.flags.Flag;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -18,7 +19,7 @@ public class FlagProtectionChangeEvent extends FlagChangeEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/flags/FlagSettingChangeEvent.java

@@ -4,6 +4,7 @@ import java.util.UUID;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.flags.Flag;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -18,7 +19,7 @@ public class FlagSettingChangeEvent extends FlagChangeEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/flags/FlagWorldSettingChangeEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.World;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.flags.Flag;
 
 /**
@@ -18,7 +19,7 @@ public class FlagWorldSettingChangeEvent extends FlagChangeEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandBanEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -19,7 +20,7 @@ public class IslandBanEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandCreateEvent.java

@@ -20,7 +20,7 @@ public class IslandCreateEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandCreatedEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -16,7 +17,7 @@ public class IslandCreatedEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandDeleteChunksEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 import world.bentobox.bentobox.database.objects.IslandDeletion;
@@ -19,7 +20,7 @@ public class IslandDeleteChunksEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandDeleteEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandDeleteEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandDeletedEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 import world.bentobox.bentobox.database.objects.IslandDeletion;
@@ -21,7 +22,7 @@ public class IslandDeletedEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandEnterEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.Event;
 import org.bukkit.event.HandlerList;
+import org.eclipse.jdt.annotation.NonNull;
 import org.eclipse.jdt.annotation.Nullable;
 
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
@@ -20,7 +21,7 @@ public class IslandEnterEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 
@@ -28,7 +29,7 @@ public class IslandEnterEvent extends IslandBaseEvent {
         return handlers;
     }
 
-    IslandEnterEvent(Island island, UUID player, boolean admin, Location location, Island fromIsland, Event rawEvent) {
+    IslandEnterEvent(Island island, UUID player, boolean admin, Location location, @Nullable Island fromIsland, Event rawEvent) {
         // Final variables have to be declared in the constructor
         super(island, player, admin, location, rawEvent);
         this.fromIsland = fromIsland;

src/main/java/world/bentobox/bentobox/api/events/island/IslandEvent.java

@@ -26,7 +26,7 @@ public class IslandEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 
@@ -425,7 +425,7 @@ public class IslandEvent extends IslandBaseEvent {
 
         private final @Nullable Island fromIsland;
 
-        private IslandEnterEvent(Island island, UUID player, boolean admin, Location location, Island fromIsland, Event rawEvent) {
+        private IslandEnterEvent(Island island, UUID player, boolean admin, Location location, @Nullable Island fromIsland, Event rawEvent) {
             // Final variables have to be declared in the constructor
             super(island, player, admin, location, rawEvent);
             this.fromIsland = fromIsland;
@@ -448,7 +448,7 @@ public class IslandEvent extends IslandBaseEvent {
         private final @Nullable Island toIsland;
 
 
-        private IslandExitEvent(Island island, UUID player, boolean admin, Location location, Island toIsland, Event rawEvent) {
+        private IslandExitEvent(Island island, UUID player, boolean admin, Location location, @Nullable Island toIsland, Event rawEvent) {
             // Final variables have to be declared in the constructor
             super(island, player, admin, location, rawEvent);
             this.toIsland = toIsland;

src/main/java/world/bentobox/bentobox/api/events/island/IslandExitEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.Event;
 import org.bukkit.event.HandlerList;
+import org.eclipse.jdt.annotation.NonNull;
 import org.eclipse.jdt.annotation.Nullable;
 
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
@@ -20,7 +21,7 @@ public class IslandExitEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 
@@ -28,7 +29,7 @@ public class IslandExitEvent extends IslandBaseEvent {
         return handlers;
     }
 
-    IslandExitEvent(Island island, UUID player, boolean admin, Location location, Island toIsland, Event rawEvent) {
+    IslandExitEvent(Island island, UUID player, boolean admin, Location location, @Nullable Island toIsland, Event rawEvent) {
         // Final variables have to be declared in the constructor
         super(island, player, admin, location, rawEvent);
         this.toIsland = toIsland;

src/main/java/world/bentobox/bentobox/api/events/island/IslandExpelEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -20,7 +21,7 @@ public class IslandExpelEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandGeneralEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandGeneralEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandLockEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandLockEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandNewIslandEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandNewIslandEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandPreCreateEvent.java

@@ -4,6 +4,7 @@ import java.util.UUID;
 
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 
 /**
@@ -16,7 +17,7 @@ public class IslandPreCreateEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandPreclearEvent.java

@@ -19,7 +19,7 @@ public class IslandPreclearEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandProtectionRangeChangeEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandProtectionRangeChangeEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandRankChangeEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -20,7 +21,7 @@ public class IslandRankChangeEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandRegisteredEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandRegisteredEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandReservedEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandReservedEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandResetEvent.java

@@ -21,7 +21,7 @@ public class IslandResetEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandResettedEvent.java

@@ -19,7 +19,7 @@ public class IslandResettedEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandUnbanEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -20,7 +21,7 @@ public class IslandUnbanEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandUnlockEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandUnlockEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/island/IslandUnregisteredEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class IslandUnregisteredEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamDeleteEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamDeleteEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamGeneralEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamGeneralEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamInfoEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamInfoEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamInviteEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamInviteEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamJoinEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamJoinEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamJoinedEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -17,7 +18,7 @@ public class TeamJoinedEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamKickEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamKickEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamLeaveEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -18,7 +19,7 @@ public class TeamLeaveEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamRejectEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamRejectEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamSetownerEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -19,7 +20,7 @@ public class TeamSetownerEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/events/team/TeamUninviteEvent.java

@@ -5,6 +5,7 @@ import java.util.UUID;
 import org.bukkit.Location;
 import org.bukkit.event.HandlerList;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.events.IslandBaseEvent;
 import world.bentobox.bentobox.database.objects.Island;
 
@@ -13,7 +14,7 @@ public class TeamUninviteEvent extends IslandBaseEvent {
     private static final HandlerList handlers = new HandlerList();
 
     @Override
-    public HandlerList getHandlers() {
+    public @NonNull HandlerList getHandlers() {
         return getHandlerList();
     }
 

src/main/java/world/bentobox/bentobox/api/flags/clicklisteners/CycleClick.java

@@ -24,7 +24,7 @@ import world.bentobox.bentobox.util.Util;
  */
 public class CycleClick implements PanelItem.ClickHandler {
 
-    protected BentoBox plugin = BentoBox.getInstance();
+    protected final BentoBox plugin = BentoBox.getInstance();
     protected Island island;
     protected User user;
     protected boolean changeOccurred;

src/main/java/world/bentobox/bentobox/api/panels/builders/PanelItemBuilder.java

@@ -137,7 +137,7 @@ public class PanelItemBuilder {
     /**
      * @return the name
      */
-    public String getName() {
+    public @Nullable String getName() {
         return name;
     }
 

src/main/java/world/bentobox/bentobox/api/placeholders/placeholderapi/AddonPlaceholderExpansion.java

@@ -1,5 +1,6 @@
 package world.bentobox.bentobox.api.placeholders.placeholderapi;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.addons.Addon;
 
 public class AddonPlaceholderExpansion extends BasicPlaceholderExpansion {
@@ -10,17 +11,17 @@ public class AddonPlaceholderExpansion extends BasicPlaceholderExpansion {
     }
 
     @Override
-    public String getName() {
+    public @NonNull String getName() {
         return addon.getDescription().getName();
     }
 
     @Override
-    public String getAuthor() {
+    public @NonNull String getAuthor() {
         return addon.getDescription().getAuthors().get(0);
     }
 
     @Override
-    public String getVersion() {
+    public @NonNull String getVersion() {
         return addon.getDescription().getVersion();
     }
 }

src/main/java/world/bentobox/bentobox/api/placeholders/placeholderapi/BasicPlaceholderExpansion.java

@@ -24,7 +24,7 @@ abstract class BasicPlaceholderExpansion extends PlaceholderExpansion {
     }
 
     @Override
-    public String getIdentifier() {
+    public @NonNull String getIdentifier() {
         return getName().toLowerCase(Locale.ENGLISH);
     }
 
@@ -42,7 +42,7 @@ abstract class BasicPlaceholderExpansion extends PlaceholderExpansion {
     }
 
     @Override
-    public String onPlaceholderRequest(Player p, String placeholder) {
+    public String onPlaceholderRequest(Player p, @NonNull String placeholder) {
         if (placeholders.containsKey(placeholder)) {
             return placeholders.get(placeholder).onReplace(User.getInstance(p));
         }

src/main/java/world/bentobox/bentobox/api/placeholders/placeholderapi/BentoBoxPlaceholderExpansion.java

@@ -1,5 +1,6 @@
 package world.bentobox.bentobox.api.placeholders.placeholderapi;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.BentoBox;
 
 public class BentoBoxPlaceholderExpansion extends BasicPlaceholderExpansion {
@@ -11,17 +12,17 @@ public class BentoBoxPlaceholderExpansion extends BasicPlaceholderExpansion {
     }
 
     @Override
-    public String getName() {
+    public @NonNull String getName() {
         return plugin.getName();
     }
 
     @Override
-    public String getAuthor() {
+    public @NonNull String getAuthor() {
         return "Tastybento and Poslovitch";
     }
 
     @Override
-    public String getVersion() {
+    public @NonNull String getVersion() {
         return plugin.getDescription().getVersion();
     }
 }

src/main/java/world/bentobox/bentobox/api/user/Notifier.java

@@ -6,6 +6,7 @@ import java.util.concurrent.TimeUnit;
 import com.google.common.cache.CacheBuilder;
 import com.google.common.cache.CacheLoader;
 import com.google.common.cache.LoadingCache;
+import org.eclipse.jdt.annotation.NonNull;
 
 /**
  * Utilities class that helps to avoid spamming the User with potential repeated messages
@@ -26,7 +27,7 @@ public class Notifier {
             .build(
                     new CacheLoader<>() {
                         @Override
-                        public Notification load(User user) {
+                        public Notification load(@NonNull User user) {
                             return new Notification(null, 0);
                         }
                     }

src/main/java/world/bentobox/bentobox/api/user/User.java

@@ -135,7 +135,7 @@ public class User implements MetaDataAble {
 
     private Addon addon;
 
-    private User(CommandSender sender) {
+    private User(@Nullable CommandSender sender) {
         player = null;
         playerUUID = null;
         this.sender = sender;

src/main/java/world/bentobox/bentobox/blueprints/Blueprint.java

@@ -79,7 +79,7 @@ public class Blueprint {
     /**
      * @return the icon
      */
-    public Material getIcon() {
+    public @NonNull Material getIcon() {
         return icon;
     }
     /**

src/main/java/world/bentobox/bentobox/blueprints/BlueprintClipboard.java

@@ -398,7 +398,7 @@ public class BlueprintClipboard {
     /**
      * @return the blueprint
      */
-    public Blueprint getBlueprint() {
+    public @Nullable Blueprint getBlueprint() {
         return blueprint;
     }
 

src/main/java/world/bentobox/bentobox/blueprints/conversation/DescriptionPrompt.java

@@ -8,6 +8,7 @@ import org.bukkit.conversations.Prompt;
 import org.bukkit.conversations.StringPrompt;
 import org.bukkit.entity.Player;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.addons.GameModeAddon;
 import world.bentobox.bentobox.api.localization.TextVariables;
 import world.bentobox.bentobox.api.user.User;
@@ -33,7 +34,7 @@ public class DescriptionPrompt extends StringPrompt {
 
     @SuppressWarnings("unchecked")
     @Override
-    public String getPromptText(ConversationContext context) {
+    public @NonNull String getPromptText(ConversationContext context) {
         User user = User.getInstance((Player)context.getForWhom());
         if (context.getSessionData(DESCRIPTION) != null) {
             StringBuilder sb = new StringBuilder();

src/main/java/world/bentobox/bentobox/blueprints/conversation/DescriptionSuccessPrompt.java

@@ -7,6 +7,7 @@ import org.bukkit.conversations.MessagePrompt;
 import org.bukkit.conversations.Prompt;
 import org.bukkit.entity.Player;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.BentoBox;
 import world.bentobox.bentobox.api.addons.GameModeAddon;
 import world.bentobox.bentobox.api.user.User;
@@ -28,7 +29,7 @@ public class DescriptionSuccessPrompt extends MessagePrompt {
     }
 
     @Override
-    public String getPromptText(ConversationContext context) {
+    public @NonNull String getPromptText(ConversationContext context) {
         User user = User.getInstance((Player)context.getForWhom());
         @SuppressWarnings("unchecked")
         List<String> description = (List<String>)context.getSessionData("description");
@@ -46,7 +47,7 @@ public class DescriptionSuccessPrompt extends MessagePrompt {
     }
 
     @Override
-    protected Prompt getNextPrompt(ConversationContext context) {
+    protected Prompt getNextPrompt(@NonNull ConversationContext context) {
         return Prompt.END_OF_CONVERSATION;
     }
 

src/main/java/world/bentobox/bentobox/blueprints/conversation/NameConversationPrefix.java

@@ -4,12 +4,13 @@ import org.bukkit.conversations.ConversationContext;
 import org.bukkit.conversations.ConversationPrefix;
 import org.bukkit.entity.Player;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.user.User;
 
 public class NameConversationPrefix implements ConversationPrefix {
 
     @Override
-    public String getPrefix(ConversationContext context) {
+    public @NonNull String getPrefix(ConversationContext context) {
         User user = User.getInstance((Player)context.getForWhom());
         return user.getTranslation("commands.admin.blueprint.management.name.conversation-prefix");
     }

src/main/java/world/bentobox/bentobox/blueprints/conversation/NamePrompt.java

@@ -38,7 +38,7 @@ public class NamePrompt extends StringPrompt {
     }
 
     @Override
-    public String getPromptText(ConversationContext context) {
+    public @NonNull String getPromptText(ConversationContext context) {
         User user = User.getInstance((Player)context.getForWhom());
         return user.getTranslation("commands.admin.blueprint.management.name.prompt");
     }

src/main/java/world/bentobox/bentobox/blueprints/conversation/NameSuccessPrompt.java

@@ -34,7 +34,7 @@ public class NameSuccessPrompt extends MessagePrompt {
     }
 
     @Override
-    public String getPromptText(ConversationContext context) {
+    public @NonNull String getPromptText(ConversationContext context) {
         String name = (String) context.getSessionData("name");
         String uniqueId = (String) context.getSessionData("uniqueId");
         User user = User.getInstance((Player)context.getForWhom());
@@ -65,7 +65,7 @@ public class NameSuccessPrompt extends MessagePrompt {
     }
 
     @Override
-    protected Prompt getNextPrompt(ConversationContext context) {
+    protected Prompt getNextPrompt(@NonNull ConversationContext context) {
         return Prompt.END_OF_CONVERSATION;
     }
 

src/main/java/world/bentobox/bentobox/database/json/BentoboxTypeAdapterFactory.java

@@ -33,7 +33,7 @@ import world.bentobox.bentobox.database.json.adapters.WorldTypeAdapter;
  */
 public class BentoboxTypeAdapterFactory implements TypeAdapterFactory {
 
-    BentoBox plugin;
+    final BentoBox plugin;
 
     /**
      * @param plugin plugin

src/main/java/world/bentobox/bentobox/database/mongodb/MongoDBDatabaseHandler.java

@@ -19,6 +19,7 @@ import com.mongodb.client.model.IndexOptions;
 import com.mongodb.client.model.Indexes;
 import com.mongodb.util.JSON;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.BentoBox;
 import world.bentobox.bentobox.database.DatabaseConnector;
 import world.bentobox.bentobox.database.json.AbstractJSONDatabaseHandler;
@@ -125,7 +126,7 @@ public class MongoDBDatabaseHandler<T> extends AbstractJSONDatabaseHandler<T> {
     }
 
     @Override
-    public T loadObject(String uniqueId) {
+    public T loadObject(@NonNull String uniqueId) {
         Document doc = collection.find(new Document(MONGO_ID, uniqueId)).limit(1).first();
         Gson gson = getGson();
         String json = JSON.serialize(doc).replaceFirst(MONGO_ID, UNIQUEID);

src/main/java/world/bentobox/bentobox/database/transition/TransitionDatabaseHandler.java

@@ -5,6 +5,7 @@ import java.lang.reflect.InvocationTargetException;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
 
+import org.eclipse.jdt.annotation.NonNull;
 import org.eclipse.jdt.annotation.Nullable;
 
 import world.bentobox.bentobox.database.AbstractDatabaseHandler;
@@ -55,7 +56,7 @@ public class TransitionDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @see world.bentobox.bentobox.database.AbstractDatabaseHandler#loadObject(java.lang.String)
      */
     @Override
-    public T loadObject(String uniqueId) throws InstantiationException, IllegalAccessException, InvocationTargetException, ClassNotFoundException, IntrospectionException, NoSuchMethodException {
+    public T loadObject(@NonNull String uniqueId) throws InstantiationException, IllegalAccessException, InvocationTargetException, ClassNotFoundException, IntrospectionException, NoSuchMethodException {
         // Try destination database
         @Nullable
         T object = toHandler.loadObject(uniqueId);

src/main/java/world/bentobox/bentobox/database/yaml/YamlDatabaseConnector.java

@@ -144,7 +144,7 @@ public class YamlDatabaseConnector implements DatabaseConnector {
         // Run through the file and add in the comments
         File commentedFile = new File(file.getPath() + ".tmp");
         List<String> newFile = new ArrayList<>();
-        try (Scanner scanner = new Scanner(file, "UTF-8")) {
+        try (Scanner scanner = new Scanner(file, StandardCharsets.UTF_8)) {
             while (scanner.hasNextLine()) {
                 String nextLine = scanner.nextLine();
                 // See if there are any comments in this line

src/main/java/world/bentobox/bentobox/database/yaml/YamlDatabaseHandler.java

@@ -80,7 +80,7 @@ public class YamlDatabaseHandler<T> extends AbstractDatabaseHandler<T> {
      * @see world.bentobox.bentobox.database.AbstractDatabaseHandler#loadObject(java.lang.String)
      */
     @Override
-    public T loadObject(String key) throws InstantiationException, IllegalAccessException, InvocationTargetException, ClassNotFoundException, IntrospectionException, NoSuchMethodException {
+    public T loadObject(@NonNull String key) throws InstantiationException, IllegalAccessException, InvocationTargetException, ClassNotFoundException, IntrospectionException, NoSuchMethodException {
         // Objects are loaded from a folder named after the simple name of the class being stored
         String path = DATABASE_FOLDER_NAME + File.separator + dataObject.getSimpleName();
         // This path and key can be overridden by the StoreAt annotation in the code

src/main/java/world/bentobox/bentobox/hooks/placeholders/PlaceholderAPIHook.java

@@ -32,7 +32,7 @@ public class PlaceholderAPIHook extends PlaceholderHook {
 
 
     public PlaceholderAPIHook() {
-        super("PlaceholderAPI");
+        super();
         this.addonsExpansions = new HashMap<>();
         this.bentoBoxPlaceholders = new HashSet<>();
         this.addonPlaceholders = new HashMap<>();

src/main/java/world/bentobox/bentobox/hooks/placeholders/PlaceholderHook.java

@@ -14,8 +14,8 @@ import world.bentobox.bentobox.api.placeholders.PlaceholderReplacer;
  */
 public abstract class PlaceholderHook extends Hook {
 
-    protected PlaceholderHook(@NonNull String pluginName) {
+    protected PlaceholderHook() {
-        super(pluginName, Material.NAME_TAG);
+        super("PlaceholderAPI", Material.NAME_TAG);
     }
 
     /**

src/main/java/world/bentobox/bentobox/listeners/flags/protection/BucketListener.java

@@ -40,15 +40,9 @@ public class BucketListener extends FlagListener {
     public void onBucketFill(final PlayerBucketFillEvent e) {
         // Check filling of various liquids
         switch (e.getItemStack().getType()) {
-            case LAVA_BUCKET -> {
+            case LAVA_BUCKET -> checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.COLLECT_LAVA);
-                checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.COLLECT_LAVA);
+            case WATER_BUCKET -> checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.COLLECT_WATER);
-            }
+            case MILK_BUCKET -> checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.MILKING);
-            case WATER_BUCKET -> {
-                checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.COLLECT_WATER);
-            }
-            case MILK_BUCKET -> {
-                checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.MILKING);
-            }
             default ->
                     // Check general bucket use
                     checkIsland(e, e.getPlayer(), e.getBlockClicked().getLocation(), Flags.BUCKET);

src/main/java/world/bentobox/bentobox/managers/IslandWorldManager.java

@@ -678,7 +678,7 @@ public class IslandWorldManager {
      * @return data folder file object or the plugin's data folder if none found
      */
     public File getDataFolder(@NonNull World world) {
-        return getAddon(world).map(GameModeAddon::getDataFolder).orElseGet(() -> plugin.getDataFolder());
+        return getAddon(world).map(GameModeAddon::getDataFolder).orElseGet(plugin::getDataFolder);
     }
 
     /**

src/main/java/world/bentobox/bentobox/managers/IslandsManager.java

@@ -129,7 +129,7 @@ public class IslandsManager {
      * Used only for testing. Sets the database to a mock database.
      * @param handler - handler
      */
-    public void setHandler(Database<Island> handler) {
+    public void setHandler(@NonNull Database<Island> handler) {
         this.handler = handler;
     }
 

src/main/java/world/bentobox/bentobox/managers/island/DefaultNewIslandLocationStrategy.java

@@ -32,7 +32,7 @@ public class DefaultNewIslandLocationStrategy implements NewIslandLocationStrate
         ISLAND_FOUND, BLOCKS_IN_AREA, FREE
     }
 
-    protected BentoBox plugin = BentoBox.getInstance();
+    protected final BentoBox plugin = BentoBox.getInstance();
 
     @Override
     public Location getNextLocation(World world) {

src/main/java/world/bentobox/bentobox/panels/settings/WorldDefaultSettingsTab.java

@@ -7,6 +7,7 @@ import java.util.stream.Collectors;
 import org.bukkit.Material;
 import org.bukkit.World;
 
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.api.flags.Flag.Type;
 import world.bentobox.bentobox.api.flags.clicklisteners.WorldToggleClick;
 import world.bentobox.bentobox.api.localization.TextVariables;
@@ -68,7 +69,7 @@ public class WorldDefaultSettingsTab extends SettingsTab implements Tab {
      * @return list of all the panel items for this flag type
      */
     @Override
-    public List<PanelItem> getPanelItems() {
+    public @NonNull List<PanelItem> getPanelItems() {
         // Different description and click handlers
         return getFlags().stream().map(f -> {
             PanelItem i = f.toPanelItem(plugin, user, null, false);

src/main/java/world/bentobox/bentobox/util/IslandInfo.java

@@ -28,7 +28,7 @@ public class IslandInfo {
 
 
     /**
-     * @param plugin
+     * Get island Info
      * @param island Island to show info
      */
     public IslandInfo(Island island) {

src/main/java/world/bentobox/bentobox/util/MyBiomeGrid.java

@@ -7,6 +7,7 @@ import org.bukkit.World.Environment;
 import org.bukkit.block.Biome;
 import org.bukkit.generator.ChunkGenerator.BiomeGrid;
 import org.bukkit.util.Vector;
+import org.eclipse.jdt.annotation.NonNull;
 
 /**
  * A biome grid for generators
@@ -37,19 +38,19 @@ public class MyBiomeGrid implements BiomeGrid {
 
     }
     @Override
-    public Biome getBiome(int x, int z) {
+    public @NonNull Biome getBiome(int x, int z) {
         return map.getOrDefault(new Vector(x,0,z), defaultBiome);
     }
     @Override
-    public void setBiome(int x, int z, Biome bio) {
+    public void setBiome(int x, int z, @NonNull Biome bio) {
         map.put(new Vector(x,0,z), bio);
     }
     @Override
-    public Biome getBiome(int x, int y, int z) {
+    public @NonNull Biome getBiome(int x, int y, int z) {
         return map.getOrDefault(new Vector(x,y,z), defaultBiome);
     }
     @Override
-    public void setBiome(int x, int y, int z, Biome bio) {
+    public void setBiome(int x, int y, int z, @NonNull Biome bio) {
         map.put(new Vector(x, y, z), bio);
 
     }