Implements the remove command

src/main/java/net/knarcraft/dropper/Dropper.java

@@ -10,6 +10,7 @@ import net.knarcraft.dropper.command.JoinArenaTabCompleter;
 import net.knarcraft.dropper.command.LeaveArenaCommand;
 import net.knarcraft.dropper.command.ListArenaCommand;
 import net.knarcraft.dropper.command.RemoveArenaCommand;
+import net.knarcraft.dropper.command.RemoveArenaTabCompleter;
 import net.knarcraft.dropper.listener.DamageListener;
 import net.knarcraft.dropper.listener.MoveListener;
 import net.knarcraft.dropper.listener.PlayerLeaveListener;
@@ -88,7 +89,7 @@ public final class Dropper extends JavaPlugin {
         registerCommand("dropperjoin", new JoinArenaCommand(), new JoinArenaTabCompleter());
         registerCommand("dropperleave", new LeaveArenaCommand(), null);
         registerCommand("dropperedit", new EditArenaCommand(), new EditArenaTabCompleter());
-        registerCommand("dropperremove", new RemoveArenaCommand(), null);
+        registerCommand("dropperremove", new RemoveArenaCommand(), new RemoveArenaTabCompleter());
     }
 
     @Override

src/main/java/net/knarcraft/dropper/arena/DropperArenaHandler.java

@@ -65,6 +65,7 @@ public class DropperArenaHandler {
      * @param arena <p>The arena to remove</p>
      */
     public void removeArena(@NotNull DropperArena arena) {
+        Dropper.getInstance().getPlayerRegistry().removeForArena(arena);
         this.arenas.remove(arena);
         this.saveArenas();
     }

src/main/java/net/knarcraft/dropper/arena/DropperArenaPlayerRegistry.java

@@ -43,4 +43,19 @@ public class DropperArenaPlayerRegistry {
         return this.arenaPlayers.getOrDefault(playerId, null);
     }
 
+    /**
+     * Removes all active sessions for the given arena
+     *
+     * @param arena <p>The arena to remove sessions for</p>
+     */
+    public void removeForArena(DropperArena arena) {
+        for (Map.Entry<UUID, DropperArenaSession> entry : this.arenaPlayers.entrySet()) {
+            if (entry.getValue().getArena() == arena) {
+                // Kick the player gracefully
+                entry.getValue().triggerQuit();
+                this.arenaPlayers.remove(entry.getKey());
+            }
+        }
+    }
+
 }

src/main/java/net/knarcraft/dropper/command/JoinArenaTabCompleter.java

@@ -1,7 +1,6 @@
 package net.knarcraft.dropper.command;
 
-import net.knarcraft.dropper.Dropper;
+import net.knarcraft.dropper.util.TabCompleteHelper;
-import net.knarcraft.dropper.arena.DropperArena;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
 import org.bukkit.command.TabCompleter;
@@ -18,14 +17,10 @@ public class JoinArenaTabCompleter implements TabCompleter {
 
     @Override
     public @Nullable List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command,
-                                                @NotNull String label, @NotNull String[] args) {
+                                                @NotNull String label, @NotNull String[] arguments) {
-        if (args.length == 1) {
+        if (arguments.length == 1) {
-            List<String> arenaNames = new ArrayList<>();
+            return TabCompleteHelper.getArenas();
-            for (DropperArena dropperArena : Dropper.getInstance().getArenaHandler().getArenas()) {
+        } else if (arguments.length == 2) {
-                arenaNames.add(dropperArena.getArenaName());
-            }
-            return arenaNames;
-        } else if (args.length == 2) {
             List<String> gameModes = new ArrayList<>();
             gameModes.add("default");
             gameModes.add("deaths");

src/main/java/net/knarcraft/dropper/command/RemoveArenaCommand.java

@@ -1,5 +1,8 @@
 package net.knarcraft.dropper.command;
 
+import net.knarcraft.dropper.Dropper;
+import net.knarcraft.dropper.arena.DropperArena;
+import net.knarcraft.dropper.util.ArenaStorageHelper;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
@@ -12,12 +15,26 @@ public class RemoveArenaCommand implements CommandExecutor {
 
     @Override
     public boolean onCommand(@NotNull CommandSender commandSender, @NotNull Command command, @NotNull String s,
-                             @NotNull String[] strings) {
+                             @NotNull String[] arguments) {
-        //TODO: Make sure to kick any playing players if the arena is currently in use, by triggering their sessions' 
+        // Get the specified arena
-        // triggerQuit() method
+        String arenaName = arguments[0];
-        //TODO: Remove the arena from DropperArenaHandler
+        String sanitized = ArenaStorageHelper.sanitizeArenaName(arenaName);
-        //TODO: Notify the user of success
+        DropperArena targetArena = null;
-        return false;
+        for (DropperArena arena : Dropper.getInstance().getArenaHandler().getArenas()) {
+            if (sanitized.equals(ArenaStorageHelper.sanitizeArenaName(arena.getArenaName()))) {
+                targetArena = arena;
+            }
+        }
+
+        if (targetArena == null) {
+            commandSender.sendMessage("Unable to find the specified arena");
+            return false;
+        }
+
+        // Remove the arena
+        Dropper.getInstance().getArenaHandler().removeArena(targetArena);
+        commandSender.sendMessage("The specified arena has been successfully removed");
+        return true;
     }
 
 }

src/main/java/net/knarcraft/dropper/command/RemoveArenaTabCompleter.java

@@ -0,0 +1,29 @@
+package net.knarcraft.dropper.command;
+
+import net.knarcraft.dropper.util.TabCompleteHelper;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabCompleter;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * The tab-completer for the remove arena command
+ */
+public class RemoveArenaTabCompleter implements TabCompleter {
+
+    @Nullable
+    @Override
+    public List<String> onTabComplete(@NotNull CommandSender commandSender, @NotNull Command command, @NotNull String s,
+                                      @NotNull String[] arguments) {
+        if (arguments.length == 1) {
+            return TabCompleteHelper.getArenas();
+        } else {
+            return new ArrayList<>();
+        }
+    }
+
+}

src/main/java/net/knarcraft/dropper/util/TabCompleteHelper.java

@@ -0,0 +1,32 @@
+package net.knarcraft.dropper.util;
+
+import net.knarcraft.dropper.Dropper;
+import net.knarcraft.dropper.arena.DropperArena;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A helper-class for common tab-completions
+ */
+public final class TabCompleteHelper {
+
+    private TabCompleteHelper() {
+
+    }
+
+    /**
+     * Gets the names of all current arenas
+     *
+     * @return <p>All arena names</p>
+     */
+    public static @NotNull List<String> getArenas() {
+        List<String> arenaNames = new ArrayList<>();
+        for (DropperArena dropperArena : Dropper.getInstance().getArenaHandler().getArenas()) {
+            arenaNames.add(dropperArena.getArenaName());
+        }
+        return arenaNames;
+    }
+
+}