simplified code: shared entity tagging, world name scheme, less boilerplate

New EntityTagUtil replaces the three copies of the tag/find/remove
logic for display and interaction entities. The pixel world naming
scheme (build, parse, recognize) now lives in one place in
PixelBlockWorld with a cached base path instead of allocating on every
event. getPixels works with int arithmetic instead of two Location
allocations per cell, setBuildingPlatform lost its copy-pasted loops
and rebuilds the flower list only once, SubCommand is an abstract base
class instead of an interface with 12 trivial getters, and dead
methods were removed.

build.gradle

@@ -45,8 +45,11 @@ processResources {
     }
 }
 
+// Zielverzeichnis über testServerPluginsDir in gradle.properties oder -PtestServerPluginsDir=... setzen
 tasks.register('copyJarToTestServer', Exec) {
-    commandLine 'cp', 'build/libs/PixelBlocks-1.0-SNAPSHOT-all.jar', '/home/lars/Documents/Minecraft/Server/pixelblocks/plugins/PixelBlocks-1.0-SNAPSHOT-all.jar'
+    def pluginsDir = providers.gradleProperty('testServerPluginsDir').getOrNull()
+    onlyIf { pluginsDir != null }
+    commandLine 'cp', "build/libs/PixelBlocks-${version}-all.jar", "${pluginsDir}/PixelBlocks-${version}-all.jar"
 }
 
 shadowJar {

src/main/java/eu/mhsl/minecraft/pixelblocks/Main.java

@@ -3,10 +3,8 @@ package eu.mhsl.minecraft.pixelblocks;
 import co.aikar.taskchain.BukkitTaskChainFactory;
 import co.aikar.taskchain.TaskChain;
 import co.aikar.taskchain.TaskChainFactory;
-import eu.mhsl.minecraft.pixelblocks.commands.CreatePixelBlockCommand;
-import eu.mhsl.minecraft.pixelblocks.commands.DestroyPixelBlocksCommand;
-import eu.mhsl.minecraft.pixelblocks.commands.ExitWorldCommand;
-import eu.mhsl.minecraft.pixelblocks.commands.GivePixelBlockCommand;
+import eu.mhsl.minecraft.pixelblocks.commands.PixelBlocksCommand;
+import org.bukkit.command.PluginCommand;
 import eu.mhsl.minecraft.pixelblocks.listeners.*;
 import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
 import org.bukkit.Bukkit;
@@ -15,10 +13,10 @@ import org.bukkit.event.Listener;
 import org.bukkit.plugin.java.JavaPlugin;
 
 import java.io.File;
-import java.sql.SQLException;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
+import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.TimeUnit;
 import java.util.logging.Logger;
 
 public final class Main extends JavaPlugin {
@@ -28,7 +26,7 @@ public final class Main extends JavaPlugin {
 
     private static TaskChainFactory taskFactory;
 
-    public final static List<PixelBlock> pixelBlocks = new ArrayList<>();
+    public final static List<PixelBlock> pixelBlocks = new CopyOnWriteArrayList<>();
 
     public static <T> TaskChain<T> sharedChain(String name) {
         return taskFactory.newSharedChain(name);
@@ -64,7 +62,7 @@ public final class Main extends JavaPlugin {
             new FallOutOfPixelBlockListener(),
             new BreakPixelListener(),
             new PlacePixelBlockListener(),
-            new PreventInventorysListener(),
+            new PreventInventoriesListener(),
             new ExitPixelWorldListener(),
             new PreventIllegalBlocksListener(),
             new BreakPixelBlockListener(),
@@ -83,10 +81,10 @@ public final class Main extends JavaPlugin {
             getServer().getPluginManager().registerEvents(listener, plugin);
         }
 
-        Objects.requireNonNull(getCommand("createpixelblock")).setExecutor(new CreatePixelBlockCommand());
-        Objects.requireNonNull(getCommand("givepixelblock")).setExecutor(new GivePixelBlockCommand());
-        Objects.requireNonNull(getCommand("exitworld")).setExecutor(new ExitWorldCommand());
-        Objects.requireNonNull(getCommand("destroypixelblocks")).setExecutor(new DestroyPixelBlocksCommand());
+        PixelBlocksCommand pixelBlocksCommand = new PixelBlocksCommand();
+        PluginCommand rootCommand = Objects.requireNonNull(getCommand("pixelblocks"));
+        rootCommand.setExecutor(pixelBlocksCommand);
+        rootCommand.setTabCompleter(pixelBlocksCommand);
 
         Bukkit.addRecipe(PixelBlockItem.getRecipe());
     }
@@ -94,11 +92,8 @@ public final class Main extends JavaPlugin {
     @Override
     public void onDisable() {
         Bukkit.getOnlinePlayers().forEach(QuitWhileInPixelBlockListener::kickPlayerOutOfWorld);
-        try {
-            database.close();
-        } catch(SQLException e) {
-            throw new RuntimeException("Failed disabling", e);
-        }
+        taskFactory.shutdown(5, TimeUnit.SECONDS);
+        database.close();
     }
 
     public static Main plugin() {

src/main/java/eu/mhsl/minecraft/pixelblocks/PixelBlockConfiguration.java

@@ -9,9 +9,9 @@ public record PixelBlockConfiguration(
     boolean onlyEditableByOwner
 ) {
     public static void setDefaults(FileConfiguration config) {
-        config.addDefault(Keys.PixelsPerBlock.key, 16);
-        config.addDefault(Keys.OnlyBreakableByOwners.key, false);
-        config.addDefault(Keys.OnlyEditableByOwners.key, true);
+        config.addDefault(Keys.PixelsPerBlock.getKey(), 16);
+        config.addDefault(Keys.OnlyBreakableByOwners.getKey(), false);
+        config.addDefault(Keys.OnlyEditableByOwners.getKey(), true);
         config.options().copyDefaults(true);
     }
 

src/main/java/eu/mhsl/minecraft/pixelblocks/PixelBlockDatabase.java

@@ -7,14 +7,38 @@ import org.bukkit.Location;
 
 import java.sql.*;
 import java.util.UUID;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
 
 public class PixelBlockDatabase {
     private final Connection db;
 
+    // Alle Statement-Zugriffe nach dem Startup laufen ausschließlich auf diesem Thread,
+    // da die geteilten PreparedStatements nicht threadsicher sind.
+    private final ExecutorService executor =
+        Executors.newSingleThreadExecutor(runnable -> new Thread(runnable, "PixelBlocks-Database"));
+
     private final PreparedStatement getAllPixelBlocks;
     private final PreparedStatement deletePixelBlock;
     private final PreparedStatement insertOrReplacePixelBlock;
 
+    private record PixelBlockRow(
+        String uuid,
+        String owner,
+        String worldName,
+        double x,
+        double y,
+        double z,
+        String entryWorldName,
+        double entryX,
+        double entryY,
+        double entryZ,
+        String direction
+    ) {
+    }
+
     public PixelBlockDatabase(String url) {
         try {
             Class.forName("org.sqlite.JDBC");
@@ -50,52 +74,78 @@ public class PixelBlockDatabase {
         }
     }
 
-    public void close() throws SQLException {
-        deletePixelBlock.close();
-        getAllPixelBlocks.close();
-        insertOrReplacePixelBlock.close();
-        db.close();
+    public void close() {
+        this.executor.shutdown();
+        try {
+            if(!this.executor.awaitTermination(10, TimeUnit.SECONDS)) {
+                Main.logger().warning("Database executor did not terminate in time, forcing shutdown");
+                this.executor.shutdownNow();
+            }
+        } catch(InterruptedException e) {
+            Thread.currentThread().interrupt();
+            this.executor.shutdownNow();
+        }
+
+        try {
+            this.deletePixelBlock.close();
+            this.getAllPixelBlocks.close();
+            this.insertOrReplacePixelBlock.close();
+            this.db.close();
+        } catch(SQLException e) {
+            Main.logger().log(Level.SEVERE, "Failed closing the database", e);
+        }
     }
 
     public void deletePixelBlock(PixelBlock pixelBlock) {
-        Bukkit.getScheduler().runTaskAsynchronously(Main.plugin(), () -> {
+        String uuid = pixelBlock.getBlockUUID().toString();
+        this.executor.execute(() -> {
             try {
-                this.deletePixelBlock.setString(1, pixelBlock.getBlockUUID().toString());
+                this.deletePixelBlock.setString(1, uuid);
                 this.deletePixelBlock.executeUpdate();
             } catch(SQLException e) {
-                throw new RuntimeException("Failed to delete PixelBlock from the database", e);
+                Main.logger().log(Level.SEVERE, String.format("Failed to delete PixelBlock '%s' from the database", uuid), e);
             }
         });
     }
 
     public void savePixelBlock(PixelBlock pixelBlock) {
-        Bukkit.getScheduler().runTask(Main.plugin(), () -> {
+        Location blockLocation = pixelBlock.getPixelBlockLocation();
+        Location entryLocation = pixelBlock.hasLastEntryLocation() ? pixelBlock.getLastEntryLocation() : blockLocation;
+
+        PixelBlockRow row = new PixelBlockRow(
+            pixelBlock.getBlockUUID().toString(),
+            pixelBlock.getOwnerUUID().toString(),
+            blockLocation.getWorld().getName(),
+            blockLocation.getX(),
+            blockLocation.getY(),
+            blockLocation.getZ(),
+            entryLocation.getWorld().getName(),
+            entryLocation.getX(),
+            entryLocation.getY(),
+            entryLocation.getZ(),
+            pixelBlock.getFacingDirection().toString()
+        );
+
+        this.executor.execute(() -> {
             try {
-                this.insertOrReplacePixelBlock.setString(1, pixelBlock.getBlockUUID().toString());
-                this.insertOrReplacePixelBlock.setString(2, pixelBlock.getOwnerUUID().toString());
+                this.insertOrReplacePixelBlock.setString(1, row.uuid());
+                this.insertOrReplacePixelBlock.setString(2, row.owner());
 
-                this.insertOrReplacePixelBlock.setString(3, pixelBlock.getPixelBlockLocation().getWorld().getName());
-                this.insertOrReplacePixelBlock.setDouble(4, pixelBlock.getPixelBlockLocation().getX());
-                this.insertOrReplacePixelBlock.setDouble(5, pixelBlock.getPixelBlockLocation().getY());
-                this.insertOrReplacePixelBlock.setDouble(6, pixelBlock.getPixelBlockLocation().getZ());
+                this.insertOrReplacePixelBlock.setString(3, row.worldName());
+                this.insertOrReplacePixelBlock.setDouble(4, row.x());
+                this.insertOrReplacePixelBlock.setDouble(5, row.y());
+                this.insertOrReplacePixelBlock.setDouble(6, row.z());
 
-                if(pixelBlock.hasLastEntryLocation()) {
-                    this.insertOrReplacePixelBlock.setString(7, pixelBlock.getLastEntryLocation().getWorld().getName());
-                    this.insertOrReplacePixelBlock.setDouble(8, pixelBlock.getLastEntryLocation().getX());
-                    this.insertOrReplacePixelBlock.setDouble(9, pixelBlock.getLastEntryLocation().getY());
-                    this.insertOrReplacePixelBlock.setDouble(10, pixelBlock.getLastEntryLocation().getZ());
-                } else {
-                    this.insertOrReplacePixelBlock.setString(7, pixelBlock.getPixelBlockLocation().getWorld().getName());
-                    this.insertOrReplacePixelBlock.setDouble(8, pixelBlock.getPixelBlockLocation().getX());
-                    this.insertOrReplacePixelBlock.setDouble(9, pixelBlock.getPixelBlockLocation().getY());
-                    this.insertOrReplacePixelBlock.setDouble(10, pixelBlock.getPixelBlockLocation().getZ());
-                }
+                this.insertOrReplacePixelBlock.setString(7, row.entryWorldName());
+                this.insertOrReplacePixelBlock.setDouble(8, row.entryX());
+                this.insertOrReplacePixelBlock.setDouble(9, row.entryY());
+                this.insertOrReplacePixelBlock.setDouble(10, row.entryZ());
 
-                this.insertOrReplacePixelBlock.setString(11, pixelBlock.getFacingDirection().toString());
+                this.insertOrReplacePixelBlock.setString(11, row.direction());
 
                 this.insertOrReplacePixelBlock.executeUpdate();
             } catch(SQLException e) {
-                throw new RuntimeException("Failed to create or update PixelBlock in the database", e);
+                Main.logger().log(Level.SEVERE, String.format("Failed to create or update PixelBlock '%s' in the database", row.uuid()), e);
             }
         });
     }
@@ -105,27 +155,32 @@ public class PixelBlockDatabase {
             ResultSet allPixelBlocks = this.getAllPixelBlocks.executeQuery();
 
             while(allPixelBlocks.next()) {
-                Location blockLocation = new Location(
-                    Bukkit.getWorld(allPixelBlocks.getString("locationWorldName")),
-                    allPixelBlocks.getDouble("locationX"),
-                    allPixelBlocks.getDouble("locationY"),
-                    allPixelBlocks.getDouble("locationZ")
-                );
+                String uuid = allPixelBlocks.getString("uuid");
+                try {
+                    Location blockLocation = new Location(
+                        Bukkit.getWorld(allPixelBlocks.getString("locationWorldName")),
+                        allPixelBlocks.getDouble("locationX"),
+                        allPixelBlocks.getDouble("locationY"),
+                        allPixelBlocks.getDouble("locationZ")
+                    );
 
-                Location entryLocation = new Location(
-                    Bukkit.getWorld(allPixelBlocks.getString("entryLocationWorldName")),
-                    allPixelBlocks.getDouble("entryLocationX"),
-                    allPixelBlocks.getDouble("entryLocationY"),
-                    allPixelBlocks.getDouble("entryLocationZ")
-                );
+                    Location entryLocation = new Location(
+                        Bukkit.getWorld(allPixelBlocks.getString("entryLocationWorldName")),
+                        allPixelBlocks.getDouble("entryLocationX"),
+                        allPixelBlocks.getDouble("entryLocationY"),
+                        allPixelBlocks.getDouble("entryLocationZ")
+                    );
 
-                Main.pixelBlocks.add(PixelBlock.fromExisting(
-                    UUID.fromString(allPixelBlocks.getString("uuid")),
-                    UUID.fromString(allPixelBlocks.getString("owner")),
-                    blockLocation,
-                    Direction.valueOf(allPixelBlocks.getString("direction")),
-                    entryLocation
-                ));
+                    Main.pixelBlocks.add(PixelBlock.fromExisting(
+                        UUID.fromString(uuid),
+                        UUID.fromString(allPixelBlocks.getString("owner")),
+                        blockLocation,
+                        Direction.valueOf(allPixelBlocks.getString("direction")),
+                        entryLocation
+                    ));
+                } catch(Exception e) {
+                    Main.logger().log(Level.SEVERE, String.format("Failed initializing existing pixelblock '%s'", uuid), e);
+                }
             }
         } catch(SQLException e) {
             throw new RuntimeException("Failed loading PixelBlocks from the database", e);

src/main/java/eu/mhsl/minecraft/pixelblocks/PixelBlockItem.java

@@ -36,6 +36,12 @@ public class PixelBlockItem {
         }
     }
 
+    public static void setBlockId(@NotNull ItemStack item, @NotNull UUID id) {
+        ItemMeta meta = item.getItemMeta();
+        meta.getPersistentDataContainer().set(idProperty, PersistentDataType.STRING, id.toString());
+        item.setItemMeta(meta);
+    }
+
     public static @Nullable BlockInfo getBlockInfo(ItemStack item) {
         PersistentDataContainer container = item.getItemMeta().getPersistentDataContainer();
         if(!container.has(idProperty)) return null;
@@ -69,7 +75,6 @@ public class PixelBlockItem {
         ItemStack item = HeadUtil.getCustomTextureHead(itemTexture);
         ItemMeta meta = item.getItemMeta();
         meta.setMaxStackSize(1);
-        meta.itemName(Component.text(emptyBlockUUID.toString()));
         meta.displayName(Component.text("Leerer Pixelblock"));
         meta.lore(List.of(
             Component.text("Der erste Spieler, der den Block platziert wird zum Besitzer des Blocks."),

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/CreatePixelBlockCommand.java

@@ -1,36 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
-import eu.mhsl.minecraft.pixelblocks.utils.Direction;
-import org.bukkit.Location;
-import org.bukkit.World;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.UUID;
-
-public class CreatePixelBlockCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            World playerWorld = p.getWorld();
-            if(PixelBlockWorld.getPixelBlockWorlds().contains(playerWorld)) {
-                p.sendMessage("Pixelblöcke können nicht innerhalb anderen Pixelblöcken erstellt werden.");
-                return true;
-            }
-
-            Location playerLocation = p.getLocation();
-            PixelBlock.createPixelBlock(
-                UUID.randomUUID(),
-                p.getUniqueId(),
-                playerLocation.toBlockLocation(),
-                Direction.south
-            );
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/CreateSubCommand.java

@@ -0,0 +1,32 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
+import eu.mhsl.minecraft.pixelblocks.utils.Direction;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.UUID;
+
+public class CreateSubCommand extends SubCommand {
+    public CreateSubCommand() {
+        super("create", "pixelblocks.command.create", "Erstellt einen neuen Pixelblock an deiner Position.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        if(PixelBlockWorld.isPixelWorld(player.getWorld())) {
+            player.sendMessage(Component.text("Pixelblöcke können nicht innerhalb anderer Pixelblöcke erstellt werden.", NamedTextColor.RED));
+            return;
+        }
+
+        PixelBlock.createPixelBlock(
+            UUID.randomUUID(),
+            player.getUniqueId(),
+            player.getLocation().toBlockLocation(),
+            Direction.south
+        );
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/DestroyAllSubCommand.java

@@ -0,0 +1,23 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.Main;
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+public class DestroyAllSubCommand extends SubCommand {
+    public DestroyAllSubCommand() {
+        super("destroyall", "pixelblocks.command.destroyall", "Zerstört alle Pixelblöcke auf dem Server.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        List<PixelBlock> blocksToDestroy = List.copyOf(Main.pixelBlocks);
+        blocksToDestroy.forEach(pixelBlock -> pixelBlock.destroy(player, true));
+        player.sendMessage(Component.text(String.format("%d Pixelblöcke werden zerstört.", blocksToDestroy.size()), NamedTextColor.GREEN));
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/DestroyPixelBlocksCommand.java

@@ -1,19 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.Main;
-import org.bukkit.Bukkit;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-
-public class DestroyPixelBlocksCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            Main.pixelBlocks.forEach(pixelBlock -> pixelBlock.destroy(Bukkit.getPlayer(pixelBlock.getOwnerUUID())));
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/ExitSubCommand.java

@@ -0,0 +1,30 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
+import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+public class ExitSubCommand extends SubCommand {
+    public ExitSubCommand() {
+        super("exit", "pixelblocks.command.exit", "Verlässt den Pixelblock, in dem du dich befindest.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        if(!PixelBlockWorld.isPixelWorld(player.getWorld())) {
+            player.sendMessage(Component.text("Du befindest dich nicht in einem Pixelblock.", NamedTextColor.RED));
+            return;
+        }
+
+        PixelBlock pixelBlock = PixelBlock.getPixelBlockFromBlockWorld(player.getWorld());
+        if(pixelBlock == null) {
+            player.sendMessage(Component.text("Dieser Pixelblock konnte nicht gefunden werden.", NamedTextColor.RED));
+            return;
+        }
+
+        pixelBlock.exitBlock(player);
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/ExitWorldCommand.java

@@ -1,30 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
-import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
-import org.bukkit.World;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.Objects;
-
-public class ExitWorldCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            World playerWorld = p.getWorld();
-            if(PixelBlockWorld.getOtherWorlds().contains(playerWorld)) {
-                p.sendMessage("Du kannst nur Pixelblöcke verlassen.");
-                return true;
-            }
-
-            PixelBlock currentPixelBlock = PixelBlock.getPixelBlockFromBlockWorld(playerWorld);
-            Objects.requireNonNull(currentPixelBlock);
-            currentPixelBlock.exitBlock(p);
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/GivePixelBlockCommand.java

@@ -1,40 +0,0 @@
-package eu.mhsl.minecraft.pixelblocks.commands;
-
-import eu.mhsl.minecraft.pixelblocks.PixelBlockItem;
-import org.bukkit.command.Command;
-import org.bukkit.command.CommandExecutor;
-import org.bukkit.command.CommandSender;
-import org.bukkit.entity.Player;
-import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.bukkit.persistence.PersistentDataContainer;
-import org.bukkit.persistence.PersistentDataType;
-import org.jetbrains.annotations.NotNull;
-
-import java.util.Objects;
-import java.util.UUID;
-
-import static eu.mhsl.minecraft.pixelblocks.PixelBlockItem.getEmptyPixelBlock;
-
-public class GivePixelBlockCommand implements CommandExecutor {
-    @Override
-    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
-        if(sender instanceof Player p) {
-            ItemStack result = getEmptyPixelBlock();
-            ItemMeta itemMeta = result.getItemMeta();
-            PersistentDataContainer dataContainer = itemMeta.getPersistentDataContainer();
-            if(!dataContainer.has(PixelBlockItem.idProperty)) return false;
-            String currentId = dataContainer.get(PixelBlockItem.idProperty, PersistentDataType.STRING);
-            Objects.requireNonNull(currentId);
-            if(!UUID.fromString(currentId).equals(PixelBlockItem.emptyBlockUUID)) return false;
-
-            dataContainer.set(PixelBlockItem.idProperty, PersistentDataType.STRING, args[0]);
-
-            result.setItemMeta(itemMeta);
-
-
-            p.getInventory().addItem(result);
-        }
-        return true;
-    }
-}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/GiveSubCommand.java

@@ -0,0 +1,44 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import eu.mhsl.minecraft.pixelblocks.PixelBlockItem;
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.entity.Player;
+import org.bukkit.inventory.ItemStack;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+import java.util.UUID;
+
+public class GiveSubCommand extends SubCommand {
+    public GiveSubCommand() {
+        super("give", "pixelblocks.command.give", "Gibt dir ein Pixelblock-Item, optional mit fester UUID.");
+    }
+
+    @Override
+    public void execute(@NotNull Player player, @NotNull String[] args) {
+        UUID blockId;
+        if(args.length == 0) {
+            blockId = UUID.randomUUID();
+        } else {
+            try {
+                blockId = UUID.fromString(args[0]);
+            } catch(IllegalArgumentException e) {
+                player.sendMessage(Component.text(String.format("'%s' ist keine gültige UUID.", args[0]), NamedTextColor.RED));
+                return;
+            }
+        }
+
+        ItemStack item = PixelBlockItem.getEmptyPixelBlock();
+        PixelBlockItem.setBlockId(item, blockId);
+
+        player.getInventory().addItem(item);
+        player.sendMessage(Component.text(String.format("Pixelblock '%s' erhalten.", blockId), NamedTextColor.GREEN));
+    }
+
+    @Override
+    public @NotNull List<String> tabComplete(@NotNull Player player, @NotNull String[] args) {
+        if(args.length == 1) return List.of("<uuid>");
+        return List.of();
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/PixelBlocksCommand.java

@@ -0,0 +1,79 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.format.NamedTextColor;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandExecutor;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabCompleter;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+
+public class PixelBlocksCommand implements CommandExecutor, TabCompleter {
+    private final List<SubCommand> subCommands = List.of(
+        new CreateSubCommand(),
+        new GiveSubCommand(),
+        new ExitSubCommand(),
+        new DestroyAllSubCommand()
+    );
+
+    @Override
+    public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
+        if(!(sender instanceof Player player)) {
+            sender.sendMessage(Component.text("Dieser Befehl kann nur von Spielern ausgeführt werden.", NamedTextColor.RED));
+            return true;
+        }
+
+        Optional<SubCommand> subCommand = args.length == 0
+            ? Optional.empty()
+            : this.subCommands.stream().filter(sub -> sub.name().equalsIgnoreCase(args[0])).findFirst();
+
+        if(subCommand.isEmpty()) {
+            this.sendUsage(player);
+            return true;
+        }
+
+        if(!player.hasPermission(subCommand.get().permission())) {
+            player.sendMessage(Component.text("Dazu hast du keine Berechtigung.", NamedTextColor.RED));
+            return true;
+        }
+
+        subCommand.get().execute(player, Arrays.copyOfRange(args, 1, args.length));
+        return true;
+    }
+
+    @Override
+    public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label, @NotNull String[] args) {
+        if(!(sender instanceof Player player)) return List.of();
+
+        if(args.length == 1) {
+            return this.subCommands.stream()
+                .filter(sub -> player.hasPermission(sub.permission()))
+                .map(SubCommand::name)
+                .filter(name -> name.startsWith(args[0].toLowerCase()))
+                .toList();
+        }
+
+        return this.subCommands.stream()
+            .filter(sub -> sub.name().equalsIgnoreCase(args[0]))
+            .filter(sub -> player.hasPermission(sub.permission()))
+            .findFirst()
+            .map(sub -> sub.tabComplete(player, Arrays.copyOfRange(args, 1, args.length)))
+            .orElse(List.of());
+    }
+
+    private void sendUsage(@NotNull Player player) {
+        player.sendMessage(Component.text("PixelBlocks-Befehle:", NamedTextColor.GOLD));
+        this.subCommands.stream()
+            .filter(sub -> player.hasPermission(sub.permission()))
+            .forEach(sub -> player.sendMessage(Component.text()
+                .append(Component.text("/pixelblocks " + sub.name(), NamedTextColor.YELLOW))
+                .append(Component.text(" - " + sub.description(), NamedTextColor.GRAY))
+                .build()));
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/commands/SubCommand.java

@@ -0,0 +1,36 @@
+package eu.mhsl.minecraft.pixelblocks.commands;
+
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+
+public abstract class SubCommand {
+    private final String name;
+    private final String permission;
+    private final String description;
+
+    protected SubCommand(@NotNull String name, @NotNull String permission, @NotNull String description) {
+        this.name = name;
+        this.permission = permission;
+        this.description = description;
+    }
+
+    public final @NotNull String name() {
+        return name;
+    }
+
+    public final @NotNull String permission() {
+        return permission;
+    }
+
+    public final @NotNull String description() {
+        return description;
+    }
+
+    public abstract void execute(@NotNull Player player, @NotNull String[] args);
+
+    public @NotNull List<String> tabComplete(@NotNull Player player, @NotNull String[] args) {
+        return List.of();
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/BreakPixelBlockListener.java

@@ -15,6 +15,6 @@ public class BreakPixelBlockListener implements Listener {
         Location blockLocation = event.getAttacked().getLocation().toBlockLocation();
         PixelBlock pixelBlock = PixelBlock.getPixelBlockFromPlacedLocation(blockLocation);
         if(pixelBlock == null) return;
-        pixelBlock.destroy(event.getPlayer());
+        pixelBlock.destroy(event.getPlayer(), false);
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/CraftPixelBlockListener.java

@@ -5,11 +5,7 @@ import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.event.inventory.CraftItemEvent;
 import org.bukkit.inventory.ItemStack;
-import org.bukkit.inventory.meta.ItemMeta;
-import org.bukkit.persistence.PersistentDataContainer;
-import org.bukkit.persistence.PersistentDataType;
 
-import java.util.Objects;
 import java.util.UUID;
 
 public class CraftPixelBlockListener implements Listener {
@@ -17,14 +13,10 @@ public class CraftPixelBlockListener implements Listener {
     public void onCraft(CraftItemEvent event) {
         ItemStack result = event.getInventory().getResult();
         if(result == null) return;
-        ItemMeta itemMeta = result.getItemMeta();
-        PersistentDataContainer dataContainer = itemMeta.getPersistentDataContainer();
-        if(!dataContainer.has(PixelBlockItem.idProperty)) return;
-        String currentId = dataContainer.get(PixelBlockItem.idProperty, PersistentDataType.STRING);
-        Objects.requireNonNull(currentId);
-        if(!UUID.fromString(currentId).equals(PixelBlockItem.emptyBlockUUID)) return;
 
-        dataContainer.set(PixelBlockItem.idProperty, PersistentDataType.STRING, UUID.randomUUID().toString());
-        result.setItemMeta(itemMeta);
+        PixelBlockItem.BlockInfo info = PixelBlockItem.getBlockInfo(result);
+        if(info == null || !info.id().equals(PixelBlockItem.emptyBlockUUID)) return;
+
+        PixelBlockItem.setBlockId(result, UUID.randomUUID());
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/DiscoverRecipesListener.java

@@ -20,7 +20,7 @@ public class DiscoverRecipesListener implements Listener {
         if(!(event.getWhoClicked() instanceof Player player)) return;
         if(!List.of(Material.HEART_OF_THE_SEA, Material.END_CRYSTAL).contains(clickedItem.getType())) return;
         if(player.hasDiscoveredRecipe(PixelBlockItem.recipeKey)) return;
-        Main.logger().log(Level.INFO, String.format("%s unlocked tne PixelBlock recipe!", player.getName()));
+        Main.logger().log(Level.INFO, String.format("%s unlocked the PixelBlock recipe!", player.getName()));
         player.discoverRecipe(PixelBlockItem.recipeKey);
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/ExitPixelWorldListener.java

@@ -1,5 +1,6 @@
 package eu.mhsl.minecraft.pixelblocks.listeners;
 
+import eu.mhsl.minecraft.pixelblocks.Main;
 import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlock;
 import eu.mhsl.minecraft.pixelblocks.pixelblock.PixelBlockWorld;
 import org.bukkit.World;
@@ -8,7 +9,6 @@ import org.bukkit.event.Listener;
 import org.bukkit.event.entity.EntityPortalEvent;
 import org.bukkit.event.player.PlayerPortalEvent;
 
-import java.util.Objects;
 
 public class ExitPixelWorldListener implements Listener {
     @EventHandler
@@ -18,7 +18,10 @@ public class ExitPixelWorldListener implements Listener {
 
         event.setCancelled(true);
         PixelBlock pixelBlock = PixelBlock.getPixelBlockFromBlockWorld(pixelBlockWorld);
-        Objects.requireNonNull(pixelBlock);
+        if(pixelBlock == null) {
+            Main.logger().warning("Player used a portal in an unknown pixel world: " + pixelBlockWorld.getName());
+            return;
+        }
         pixelBlock.exitBlock(event.getPlayer());
     }
 

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/FallOutOfPixelBlockListener.java

@@ -7,7 +7,6 @@ import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.event.player.PlayerMoveEvent;
 
-import java.util.Objects;
 
 public class FallOutOfPixelBlockListener implements Listener {
     @EventHandler
@@ -17,7 +16,7 @@ public class FallOutOfPixelBlockListener implements Listener {
         if(!PixelBlockWorld.isPixelWorld(player.getWorld())) return;
 
         PixelBlock pixelBlock = PixelBlock.getPixelBlockFromBlockWorld(player.getWorld());
-        Objects.requireNonNull(pixelBlock);
+        if(pixelBlock == null) return;
         player.teleport(pixelBlock.getPixelWorld().getSpawnLocation());
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/PlacePixelBlockListener.java

@@ -29,6 +29,12 @@ public class PlacePixelBlockListener implements Listener {
             return;
         }
 
+        if(PixelBlock.exists(info.id())) {
+            event.getPlayer().sendMessage(Component.text("Dieser Pixelblock existiert bereits in der Welt!", NamedTextColor.RED));
+            event.setCancelled(true);
+            return;
+        }
+
         Location newBlockLocation = event.getBlock().getLocation();
         playerWorld.getBlockAt(newBlockLocation).setType(Material.AIR);
 

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/PlacePixelListener.java

@@ -17,7 +17,7 @@ public class PlacePixelListener implements Listener {
     }
 
     @EventHandler
-    public void onBuketEmpty(PlayerBucketEmptyEvent event) {
+    public void onBucketEmpty(PlayerBucketEmptyEvent event) {
         EventCanceling.shouldCancelInPixelBlock(
             event,
             event.getBlock().getWorld(),

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/PreventInventoriesListener.java

@@ -10,7 +10,7 @@ import org.bukkit.inventory.CraftingInventory;
 import org.bukkit.inventory.Inventory;
 import org.bukkit.inventory.PlayerInventory;
 
-public class PreventInventorysListener implements Listener {
+public class PreventInventoriesListener implements Listener {
     @EventHandler
     public void onInventoryOpen(InventoryOpenEvent event) {
         EventCanceling.shouldCancelInPixelBlock(

src/main/java/eu/mhsl/minecraft/pixelblocks/listeners/QuitWhileInPixelBlockListener.java

@@ -8,7 +8,6 @@ import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.event.player.PlayerQuitEvent;
 
-import java.util.Objects;
 
 public class QuitWhileInPixelBlockListener implements Listener {
     @EventHandler
@@ -20,7 +19,7 @@ public class QuitWhileInPixelBlockListener implements Listener {
         World pixelBlockWorld = player.getLocation().getWorld();
         if(!PixelBlockWorld.isPixelWorld(pixelBlockWorld)) return;
         PixelBlock pixelBlock = PixelBlock.getPixelBlockFromBlockWorld(pixelBlockWorld);
-        Objects.requireNonNull(pixelBlock);
+        if(pixelBlock == null) return;
         pixelBlock.exitBlock(player);
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/pixelblock/PixelBlock.java

@@ -38,18 +38,16 @@ public class PixelBlock {
     private final UUID blockUUID;
 
     public static @Nullable PixelBlock getPixelBlockFromBlockWorld(World world) {
+        UUID worldUUID = PixelBlockWorld.getUUIDFromWorld(world);
+        if(worldUUID == null) return null;
         return Main.pixelBlocks.stream()
-            .filter(block -> block.blockUUID.equals(getUUIDFromWorld(world)))
+            .filter(block -> block.blockUUID.equals(worldUUID))
             .findFirst()
             .orElse(null);
     }
 
-    public static @Nullable UUID getUUIDFromWorld(@NotNull World world) {
-        try {
-            return UUID.fromString(List.of(world.getName().split("/")).getLast());
-        } catch(IllegalArgumentException e) {
-            return null;
-        }
+    public static boolean exists(@NotNull UUID blockUUID) {
+        return Main.pixelBlocks.stream().anyMatch(pixelBlock -> pixelBlock.blockUUID.equals(blockUUID));
     }
 
     public static @Nullable PixelBlock getPixelBlockFromPlacedLocation(@NotNull Location placedLocation) {
@@ -76,19 +74,15 @@ public class PixelBlock {
         this.facingDirection = direction;
         this.lastEntryLocation = lastEntryLocation;
 
-        try {
-            this.pixelWorld = new PixelBlockWorld(this);
-            this.pixelData = this.pixelWorld.getPixels(this.facingDirection);
-            this.pixels = new Pixels(this);
-            this.placeholder = new PixelBlockPlaceholder(this);
-            this.hitbox = new PixelBlockHitbox(this);
+        this.pixelWorld = new PixelBlockWorld(this);
+        this.pixelData = this.pixelWorld.getPixels(this.facingDirection);
+        this.pixels = new Pixels(this);
+        this.placeholder = new PixelBlockPlaceholder(this);
+        this.hitbox = new PixelBlockHitbox(this);
 
-            this.getBlockTaskChain().sync(() -> this.isAccessible = true).execute();
+        this.getBlockTaskChain().sync(() -> this.isAccessible = true).execute();
 
-            Main.logger().info(String.format("Loaded existing pixelblock '%s'", this.blockUUID));
-        } catch(Exception e) {
-            Main.logger().info(String.format("Failed initializing existing pixelblock '%s': %s", this.blockUUID, e.getMessage()));
-        }
+        Main.logger().info(String.format("Loaded existing pixelblock '%s'", this.blockUUID));
     }
 
     public static PixelBlock createPixelBlock(UUID blockUUID, UUID ownerUUID, Location pixelBlockLocation, Direction direction) {
@@ -96,8 +90,8 @@ public class PixelBlock {
     }
 
     private PixelBlock(UUID blockUUID, UUID ownerUUID, Location pixelBlockLocation, Direction direction) {
-        if(Main.pixelBlocks.stream().anyMatch(pixelBlock -> pixelBlock.getBlockUUID().equals(blockUUID)))
-            throw new IllegalStateException(String.format("PixelBlock '%s' ist bereits in der Welt vorhanden!", blockUUID));
+        if(exists(blockUUID))
+            throw new IllegalStateException(String.format("PixelBlock '%s' already exists in the world!", blockUUID));
 
         this.blockUUID = blockUUID;
         this.ownerUUID = ownerUUID;
@@ -118,12 +112,8 @@ public class PixelBlock {
 
         this.scheduleEntityUpdate();
 
-        this.getBlockTaskChain()
-            .async(() -> {
-                Main.database().savePixelBlock(this);
-                Main.pixelBlocks.add(this);
-            })
-            .execute();
+        Main.database().savePixelBlock(this);
+        Main.pixelBlocks.add(this);
 
         this.getBlockTaskChain().sync(() -> this.isAccessible = true).execute();
     }
@@ -139,9 +129,9 @@ public class PixelBlock {
         }
 
         this.lastEntryLocation = player.getLocation();
+        Main.database().savePixelBlock(this);
 
         getBlockTaskChain()
-            .async(() -> Main.database().savePixelBlock(this))
             .sync(() -> {
                 if(!this.isAccessible) return;
                 player.teleport(this.pixelWorld.getSpawnLocation());
@@ -153,7 +143,7 @@ public class PixelBlock {
 
     public void exitBlock(@NotNull Player player) {
         this.getBlockTaskChain()
-            .sync(() -> player.teleport(this.lastEntryLocation != null ? this.lastEntryLocation : this.pixelBlockLocation))
+            .sync(() -> player.teleport(this.getReturnLocation()))
             .sync(() -> this.pixelData = this.pixelWorld.getPixels(this.facingDirection))
             .current(() -> Main.logger().info(String.format("%s exited PixelBlock", player.getName())))
             .delay(1)
@@ -178,16 +168,17 @@ public class PixelBlock {
             .execute();
     }
 
-    public void destroy(Player destroyedBy) {
+    public void destroy(Player destroyedBy, boolean force) {
         if(!this.isAccessible) return;
-        if(Main.configuration().onlyBreakableByOwner() && !destroyedBy.getUniqueId().equals(ownerUUID)) {
-            destroyedBy.sendMessage("Dieser Pixelblock gehört nicht dir!");
+        if(!force && Main.configuration().onlyBreakableByOwner() && !destroyedBy.getUniqueId().equals(ownerUUID)) {
+            destroyedBy.sendMessage(Component.text("Dieser Pixelblock gehört nicht dir!", NamedTextColor.RED));
             return;
         }
 
+        Location returnLocation = this.getReturnLocation();
         this.pixelWorld.getPlayersInWorld().forEach(p -> {
             p.sendMessage(Component.text("Der Pixelblock wurde von einem anderen Spieler abgebaut!", NamedTextColor.RED));
-            p.teleport(this.lastEntryLocation);
+            p.teleport(returnLocation);
         });
 
         Main.logger().info(String.format("Destroying PixelBlock '%s' at %s", this.blockUUID, pixelBlockLocation));
@@ -195,20 +186,19 @@ public class PixelBlock {
 
         this.pixelWorld.getEntitiesInWorld().stream()
             .filter(entity -> entity instanceof Item)
-            .forEach(entity -> entity.teleport(this.lastEntryLocation));
+            .forEach(entity -> entity.teleport(returnLocation));
 
         this.getBlockTaskChain()
             .sync(() -> {
                 this.removeEntities();
                 World world = this.pixelBlockLocation.getWorld();
-                world.playSound(this.pixelBlockLocation, Sound.BLOCK_COPPER_BULB_BREAK, 1.0F, 30);
-                world.dropItem(this.pixelBlockLocation.add(new Vector(0.5, 0.5, 0.5)), PixelBlockItem.getBlockAsItem(this));
-            })
-            .async(() -> {
-                Main.database().deletePixelBlock(this);
-                Main.pixelBlocks.remove(this);
+                world.playSound(this.pixelBlockLocation, Sound.BLOCK_COPPER_BULB_BREAK, 1.0F, 2.0F);
+                world.dropItem(this.getPixelBlockLocation().add(new Vector(0.5, 0.5, 0.5)), PixelBlockItem.getBlockAsItem(this));
             })
             .execute();
+
+        Main.database().deletePixelBlock(this);
+        Main.pixelBlocks.remove(this);
     }
 
     private void removeEntities() {
@@ -243,6 +233,12 @@ public class PixelBlock {
         return this.lastEntryLocation != null;
     }
 
+    private @NotNull Location getReturnLocation() {
+        return this.hasLastEntryLocation()
+            ? this.lastEntryLocation.clone()
+            : this.getPixelBlockLocation().add(0.5, 0, 0.5);
+    }
+
     public List<PixelBlockWorld.PixelData> getPixelData() {
         return pixelData;
     }

src/main/java/eu/mhsl/minecraft/pixelblocks/pixelblock/PixelBlockHitbox.java

@@ -1,16 +1,14 @@
 package eu.mhsl.minecraft.pixelblocks.pixelblock;
 
 import eu.mhsl.minecraft.pixelblocks.Main;
+import eu.mhsl.minecraft.pixelblocks.utils.EntityTagUtil;
 import eu.mhsl.minecraft.pixelblocks.utils.MinMaxUtil;
 import org.bukkit.Location;
 import org.bukkit.NamespacedKey;
-import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 import org.bukkit.entity.Interaction;
-import org.bukkit.persistence.PersistentDataType;
 
 import java.util.List;
-import java.util.Objects;
 
 public class PixelBlockHitbox {
     private static final NamespacedKey hitboxOfTag = new NamespacedKey(Main.plugin(), "hitbox_of");
@@ -29,7 +27,7 @@ public class PixelBlockHitbox {
         Interaction interaction;
         if (pixels.size() <= 5) {
             interaction = (Interaction) absoluteLocation.getWorld().spawnEntity(
-                absoluteLocation.clone().add(0.5, -0, 0.5),
+                absoluteLocation.clone().add(0.5, 0, 0.5),
                 EntityType.INTERACTION
             );
             interaction.setInteractionHeight(1);
@@ -45,7 +43,7 @@ public class PixelBlockHitbox {
 
             Location spawnLocation = absoluteLocation.clone().add(
                 ((startingX+endingX)/2+0.5)/pixelsPerBlock,
-                (startingY/pixelsPerBlock)-0,
+                startingY/pixelsPerBlock,
                 ((startingZ+endingZ)/2+0.5)/pixelsPerBlock
             );
 
@@ -81,19 +79,10 @@ public class PixelBlockHitbox {
             interaction.setInteractionWidth(width);
         }
 
-        interaction.getPersistentDataContainer()
-            .set(hitboxOfTag, PersistentDataType.STRING, this.parentBlock.getBlockUUID().toString());
+        EntityTagUtil.tag(interaction, hitboxOfTag, this.parentBlock.getBlockUUID());
     }
 
-
     public void destroy() {
-        this.parentBlock.getPixelBlockLocation().getNearbyEntitiesByType(Interaction.class, 1)
-            .stream()
-            .filter(interaction -> interaction.getPersistentDataContainer().has(hitboxOfTag))
-            .filter(interaction -> Objects.equals(
-                interaction.getPersistentDataContainer().get(hitboxOfTag, PersistentDataType.STRING),
-                parentBlock.getBlockUUID().toString()
-            ))
-            .forEach(Entity::remove);
+        EntityTagUtil.removeTagged(this.parentBlock.getPixelBlockLocation(), Interaction.class, hitboxOfTag, this.parentBlock.getBlockUUID());
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/pixelblock/PixelBlockPlaceholder.java

@@ -1,21 +1,18 @@
 package eu.mhsl.minecraft.pixelblocks.pixelblock;
 
 import eu.mhsl.minecraft.pixelblocks.Main;
+import eu.mhsl.minecraft.pixelblocks.utils.EntityTagUtil;
 import org.bukkit.Location;
 import org.bukkit.Material;
 import org.bukkit.NamespacedKey;
 import org.bukkit.World;
-import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
 import org.bukkit.entity.ItemDisplay;
 import org.bukkit.inventory.ItemStack;
-import org.bukkit.persistence.PersistentDataHolder;
-import org.bukkit.persistence.PersistentDataType;
 import org.bukkit.util.Transformation;
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.Objects;
 import java.util.UUID;
 
 public class PixelBlockPlaceholder {
@@ -67,20 +64,10 @@ public class PixelBlockPlaceholder {
         displayContainer.setItemStack(ItemStack.of(Material.WHITE_STAINED_GLASS));
         placeholders.add(displayContainer);
 
-        placeholders.stream()
-            .map(PersistentDataHolder::getPersistentDataContainer)
-            .forEach(container -> container.set(placeholderOfTag, PersistentDataType.STRING, parentBlockUUID.toString()));
+        placeholders.forEach(placeholder -> EntityTagUtil.tag(placeholder, placeholderOfTag, parentBlockUUID));
     }
 
     public void destroy() {
-        this.parentBlock.getPixelBlockLocation()
-            .getNearbyEntitiesByType(ItemDisplay.class, 1)
-            .stream()
-            .filter(itemDisplay -> itemDisplay.getPersistentDataContainer().has(placeholderOfTag))
-            .filter(itemDisplay -> Objects.equals(
-                itemDisplay.getPersistentDataContainer().get(placeholderOfTag, PersistentDataType.STRING),
-                parentBlock.getBlockUUID().toString()
-            ))
-            .forEach(Entity::remove);
+        EntityTagUtil.removeTagged(this.parentBlock.getPixelBlockLocation(), ItemDisplay.class, placeholderOfTag, this.parentBlock.getBlockUUID());
     }
 }

src/main/java/eu/mhsl/minecraft/pixelblocks/pixelblock/PixelBlockWorld.java

@@ -4,6 +4,7 @@ import eu.mhsl.minecraft.pixelblocks.Main;
 import eu.mhsl.minecraft.pixelblocks.utils.Direction;
 import eu.mhsl.minecraft.pixelblocks.utils.LocationUtil;
 import org.bukkit.*;
+import org.bukkit.block.Block;
 import org.bukkit.block.BlockState;
 import org.bukkit.block.data.BlockData;
 import org.bukkit.block.data.Directional;
@@ -20,6 +21,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
 import java.util.Random;
+import java.util.UUID;
 
 public class PixelBlockWorld {
     private final PixelBlock parentPixelBlock;
@@ -28,16 +30,28 @@ public class PixelBlockWorld {
     int worldGrassBorderWidth = 10;
     int pixelsPerBlock = Main.configuration().pixelsPerBlock();
 
+    // Kapselt das Namensschema der Pixelwelten: <dataFolder>/worlds/<blockUUID>
+    private static String worldsBasePath;
+
+    private static @NotNull String getWorldsBasePath() {
+        if(worldsBasePath == null) {
+            worldsBasePath = Main.plugin().getDataFolder().getPath() + File.separator + "worlds";
+        }
+        return worldsBasePath;
+    }
+
     public static boolean isPixelWorld(@NotNull World world) {
-        return world.getName().startsWith(Main.plugin().getDataFolder().getPath());
+        return world.getName().startsWith(getWorldsBasePath());
     }
 
-    public static @NotNull List<World> getOtherWorlds() {
-        return Bukkit.getWorlds().stream().filter(w -> !PixelBlockWorld.isPixelWorld(w)).toList();
-    }
-
-    public static @NotNull List<World> getPixelBlockWorlds() {
-        return Bukkit.getWorlds().stream().filter(PixelBlockWorld::isPixelWorld).toList();
+    public static @Nullable UUID getUUIDFromWorld(@NotNull World world) {
+        if(!isPixelWorld(world)) return null;
+        String worldName = world.getName();
+        try {
+            return UUID.fromString(worldName.substring(worldName.lastIndexOf(File.separatorChar) + 1));
+        } catch(IllegalArgumentException e) {
+            return null;
+        }
     }
 
     public PixelBlockWorld(PixelBlock parentPixelBlock) {
@@ -55,7 +69,7 @@ public class PixelBlockWorld {
     }
 
     public @NotNull String getWorldPathName() {
-        return Main.plugin().getDataFolder().getPath() + File.separator + "worlds" + File.separator + this.parentPixelBlock.getBlockUUID();
+        return getWorldsBasePath() + File.separator + this.parentPixelBlock.getBlockUUID();
     }
 
     public @NotNull Location getSpawnLocation() {
@@ -78,10 +92,6 @@ public class PixelBlockWorld {
         return new Location(this.world, 0, -60, 0);
     }
 
-    public @NotNull Location getBuildOriginEnd() {
-        return getBuildOrigin().add(pixelsPerBlock, pixelsPerBlock, pixelsPerBlock);
-    }
-
     public @NotNull Location getBorderOrigin() {
         return getBuildOrigin().subtract(1, 1, 1);
     }
@@ -99,31 +109,32 @@ public class PixelBlockWorld {
 
     public List<PixelData> getPixels(Direction direction) {
         List<PixelData> pixelData = new ArrayList<>();
+        Location origin = this.getBuildOrigin();
+        int max = pixelsPerBlock - 1;
 
         for(int x = 0; x < pixelsPerBlock; x++) {
             for(int y = 0; y < pixelsPerBlock; y++) {
                 for(int z = 0; z < pixelsPerBlock; z++) {
-                    Location relativeLocation = new Location(world, x, y, z);
+                    int blockX = switch(direction) {
+                        case south -> x;
+                        case north -> max - x;
+                        case east -> max - z;
+                        case west -> z;
+                    };
+                    int blockZ = switch(direction) {
+                        case south -> z;
+                        case north -> max - z;
+                        case east -> x;
+                        case west -> max - x;
+                    };
+
+                    Block block = this.world.getBlockAt(origin.getBlockX() + blockX, origin.getBlockY() + y, origin.getBlockZ() + blockZ);
+                    BlockData blockData = block.getBlockData();
+                    if(blockData.getMaterial().isAir()) continue;
 
-                    Location blockLocation = this.getBuildOrigin();
-                    switch(direction) {
-                        case south ->
-                            blockLocation.add(relativeLocation.x(), relativeLocation.y(), relativeLocation.z());
-                        case north ->
-                            blockLocation.add((pixelsPerBlock - 1) - relativeLocation.x(), relativeLocation.y(), (pixelsPerBlock - 1) - relativeLocation.z());
-                        case east ->
-                            blockLocation.add((pixelsPerBlock - 1) - relativeLocation.z(), relativeLocation.y(), relativeLocation.x());
-                        case west ->
-                            blockLocation.add(relativeLocation.z(), relativeLocation.y(), (pixelsPerBlock - 1) - relativeLocation.x());
-                    }
-                    BlockData blockData = blockLocation.getBlock().getBlockData();
                     @Nullable Directional directional = blockData instanceof Directional face ? face : null;
                     @Nullable Rotatable rotatable = blockData instanceof Rotatable rotation ? rotation : null;
-                    BlockState state = blockLocation.getBlock().getState();
-
-                    if(!blockData.getMaterial().isAir()) {
-                        pixelData.add(new PixelData(relativeLocation.toVector(), blockData, directional, rotatable, state, (double) 1 / pixelsPerBlock));
-                    }
+                    pixelData.add(new PixelData(new Vector(x, y, z), blockData, directional, rotatable, block.getState(), (double) 1 / pixelsPerBlock));
                 }
             }
         }
@@ -156,27 +167,38 @@ public class PixelBlockWorld {
         return world;
     }
 
+    private static final List<Material> FLOWERS = List.of(
+        Material.DANDELION,
+        Material.POPPY,
+        Material.BLUE_ORCHID,
+        Material.ALLIUM,
+        Material.AZURE_BLUET,
+        Material.RED_TULIP,
+        Material.ORANGE_TULIP,
+        Material.WHITE_TULIP,
+        Material.CORNFLOWER,
+        Material.LILY_OF_THE_VALLEY,
+        Material.SHORT_GRASS,
+        Material.TALL_GRASS
+    );
+
     private void setBuildingPlatform() {
         Bukkit.getScheduler().runTask(Main.plugin(), () -> {
-            for(int x = 0; x < (pixelsPerBlock + 2) + 2 * worldGrassBorderWidth; x++) {
-                for(int z = 0; z < (pixelsPerBlock + 2) + 2 * worldGrassBorderWidth; z++) {
-                    getPlatformOrigin().add(x, 0, z).getBlock().setType(Material.GRASS_BLOCK);
-                }
-            }
-            for(int x = 0; x < (pixelsPerBlock + 2) + 2 * worldGrassBorderWidth; x++) {
-                for(int z = 0; z < (pixelsPerBlock + 2) + 2 * worldGrassBorderWidth; z++) {
-                    getPlatformOrigin().add(x, -1, z).getBlock().setType(Material.DIRT);
+            int platformSize = (pixelsPerBlock + 2) + 2 * worldGrassBorderWidth;
+            Location platformOrigin = this.getPlatformOrigin();
+            for(int x = 0; x < platformSize; x++) {
+                for(int z = 0; z < platformSize; z++) {
+                    platformOrigin.clone().add(x, 0, z).getBlock().setType(Material.GRASS_BLOCK);
+                    platformOrigin.clone().add(x, -1, z).getBlock().setType(Material.DIRT);
                 }
             }
 
-            for(int x = 0; x < (pixelsPerBlock + 2); x++) {
-                for(int z = 0; z < (pixelsPerBlock + 2); z++) {
-                    Location currentLocation = getBorderOrigin().add(x, 0, z);
-
-                    if(currentLocation.x() == getBorderOrigin().x() || currentLocation.z() == getBorderOrigin().z()) {
-                        currentLocation.getBlock().setType(Material.RED_CONCRETE);
-                    } else if(currentLocation.x() == getBorderOrigin().x() + (pixelsPerBlock + 1) || currentLocation.z() == getBorderOrigin().z() + (pixelsPerBlock + 1)) {
-                        currentLocation.getBlock().setType(Material.RED_CONCRETE);
+            int borderSize = pixelsPerBlock + 2;
+            Location borderOrigin = this.getBorderOrigin();
+            for(int x = 0; x < borderSize; x++) {
+                for(int z = 0; z < borderSize; z++) {
+                    if(x == 0 || z == 0 || x == borderSize - 1 || z == borderSize - 1) {
+                        borderOrigin.clone().add(x, 0, z).getBlock().setType(Material.RED_CONCRETE);
                     }
                 }
             }
@@ -186,37 +208,23 @@ public class PixelBlockWorld {
                 if(allowPlacements(location)) return;
                 if(!location.clone().subtract(0, 1, 0).getBlock().getType().equals(Material.GRASS_BLOCK)) return;
 
-                List<Material> flowers = List.of(
-                    Material.DANDELION,
-                    Material.POPPY,
-                    Material.BLUE_ORCHID,
-                    Material.ALLIUM,
-                    Material.AZURE_BLUET,
-                    Material.RED_TULIP,
-                    Material.ORANGE_TULIP,
-                    Material.WHITE_TULIP,
-                    Material.CORNFLOWER,
-                    Material.LILY_OF_THE_VALLEY,
-                    Material.SHORT_GRASS,
-                    Material.TALL_GRASS
-                );
-                if(flowers.contains(location.getBlock().getType())) location.getBlock().setType(Material.AIR);
+                if(FLOWERS.contains(location.getBlock().getType())) location.getBlock().setType(Material.AIR);
                 if(!location.getBlock().getType().equals(Material.AIR)) return;
 
                 if(random.nextInt(30) == 0) {
-                    Material randomFlower = flowers.get(random.nextInt(flowers.size()));
-                    location.getBlock().setType(randomFlower);
+                    location.getBlock().setType(FLOWERS.get(random.nextInt(FLOWERS.size())));
                 }
             });
 
+            Location portalLocation = this.getPortalLocation();
             for(int x = 0; x < 4; x++) {
                 for(int y = 0; y < 5; y++) {
-                    getPortalLocation().add(x, y, 0).getBlock().setType(Material.OBSIDIAN);
+                    portalLocation.clone().add(x, y, 0).getBlock().setType(Material.OBSIDIAN);
                 }
             }
             for(int x = 1; x < 3; x++) {
                 for(int y = 1; y < 4; y++) {
-                    getPortalLocation().add(x, y, 0).getBlock().setType(Material.NETHER_PORTAL);
+                    portalLocation.clone().add(x, y, 0).getBlock().setType(Material.NETHER_PORTAL);
                 }
             }
         });

src/main/java/eu/mhsl/minecraft/pixelblocks/pixelblock/Pixels.java

@@ -2,6 +2,7 @@ package eu.mhsl.minecraft.pixelblocks.pixelblock;
 
 import eu.mhsl.minecraft.pixelblocks.Main;
 import eu.mhsl.minecraft.pixelblocks.utils.Direction;
+import eu.mhsl.minecraft.pixelblocks.utils.EntityTagUtil;
 import eu.mhsl.minecraft.pixelblocks.utils.ListUtil;
 import org.bukkit.Location;
 import org.bukkit.NamespacedKey;
@@ -16,7 +17,6 @@ import org.bukkit.block.data.type.EnderChest;
 import org.bukkit.entity.BlockDisplay;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.EntityType;
-import org.bukkit.persistence.PersistentDataType;
 import org.bukkit.util.Transformation;
 import org.bukkit.util.Vector;
 import org.jetbrains.annotations.NotNull;
@@ -24,7 +24,6 @@ import org.jetbrains.annotations.Nullable;
 import org.joml.Vector3d;
 
 import java.util.List;
-import java.util.Objects;
 
 public class Pixels {
     private static final NamespacedKey pixelOfTag = new NamespacedKey(Main.plugin(), "pixel_of");
@@ -61,18 +60,16 @@ public class Pixels {
         transform.getTranslation().set(centerOffset.mul(-1));
         entity.setTransformation(transform);
 
-        entity.getPersistentDataContainer().set(pixelOfTag, PersistentDataType.STRING, this.parentBlock.getBlockUUID().toString());
+        EntityTagUtil.tag(entity, pixelOfTag, this.parentBlock.getBlockUUID());
     }
 
     public void destroy() {
-        List<BlockDisplay> entities = parentBlock.getPixelBlockLocation().getNearbyEntitiesByType(BlockDisplay.class, 1)
-            .stream()
-            .filter(blockDisplay -> blockDisplay.getPersistentDataContainer().has(pixelOfTag))
-            .filter(blockDisplay -> Objects.equals(
-                blockDisplay.getPersistentDataContainer().get(pixelOfTag, PersistentDataType.STRING),
-                parentBlock.getBlockUUID().toString()
-            ))
-            .toList();
+        List<BlockDisplay> entities = EntityTagUtil.findTagged(
+            this.parentBlock.getPixelBlockLocation(),
+            BlockDisplay.class,
+            pixelOfTag,
+            this.parentBlock.getBlockUUID()
+        );
 
         ListUtil.splitListInParts(10, entities)
             .forEach(pixels -> parentBlock.getBlockTaskChain()

src/main/java/eu/mhsl/minecraft/pixelblocks/utils/EntityTagUtil.java

@@ -0,0 +1,29 @@
+package eu.mhsl.minecraft.pixelblocks.utils;
+
+import org.bukkit.Location;
+import org.bukkit.NamespacedKey;
+import org.bukkit.entity.Entity;
+import org.bukkit.persistence.PersistentDataType;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.List;
+import java.util.Objects;
+import java.util.UUID;
+
+public class EntityTagUtil {
+    public static void tag(@NotNull Entity entity, @NotNull NamespacedKey key, @NotNull UUID id) {
+        entity.getPersistentDataContainer().set(key, PersistentDataType.STRING, id.toString());
+    }
+
+    public static <T extends Entity> @NotNull List<T> findTagged(@NotNull Location center, @NotNull Class<T> type, @NotNull NamespacedKey key, @NotNull UUID id) {
+        String idString = id.toString();
+        return center.getNearbyEntitiesByType(type, 1)
+            .stream()
+            .filter(entity -> Objects.equals(entity.getPersistentDataContainer().get(key, PersistentDataType.STRING), idString))
+            .toList();
+    }
+
+    public static <T extends Entity> void removeTagged(@NotNull Location center, @NotNull Class<T> type, @NotNull NamespacedKey key, @NotNull UUID id) {
+        findTagged(center, type, key, id).forEach(Entity::remove);
+    }
+}

src/main/java/eu/mhsl/minecraft/pixelblocks/utils/EventCanceling.java

@@ -14,7 +14,7 @@ public class EventCanceling {
         if(!PixelBlockWorld.isPixelWorld(world)) return;
         @Nullable PixelBlock pixelBlock = PixelBlock.getPixelBlockFromBlockWorld(world);
         if(pixelBlock == null) {
-            Main.logger().warning("Cancelling place event because PixelBlock could not be found: " + world.getName());
+            Main.logger().warning("Cancelling %s event because PixelBlock '%s' could not be found!".formatted(event.getClass().getSimpleName(), world.getName()));
             event.setCancelled(true);
             return;
         }

src/main/resources/plugin.yml

@@ -3,7 +3,20 @@ version: '${version}'
 main: eu.mhsl.minecraft.pixelblocks.Main
 api-version: '1.21'
 commands:
-  createpixelblock:
-  exitworld:
-  givepixelblock:
-  destroypixelblocks:
+  pixelblocks:
+    description: Verwaltung von Pixelblöcken
+    usage: /pixelblocks <create|give|exit|destroyall>
+    aliases: [pb]
+permissions:
+  pixelblocks.command.create:
+    description: Erlaubt das Erstellen eines Pixelblocks per Befehl
+    default: op
+  pixelblocks.command.give:
+    description: Erlaubt das Geben von Pixelblock-Items
+    default: op
+  pixelblocks.command.exit:
+    description: Erlaubt das Verlassen eines Pixelblocks per Befehl
+    default: true
+  pixelblocks.command.destroyall:
+    description: Erlaubt das Zerstören aller Pixelblöcke
+    default: op