did a bit of refactoring

src/main/java/net/nuggetmc/tplus/command/CommandInstance.java

@@ -0,0 +1,97 @@
+package net.nuggetmc.tplus.command;
+
+import net.md_5.bungee.api.ChatColor;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.defaults.BukkitCommand;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.*;
+import java.util.stream.Collectors;
+
+public abstract class CommandInstance extends BukkitCommand {
+
+    protected final CommandHandler commandHandler;
+
+    private final Map<String, CommandMethod> methods;
+
+    private static final String MANAGE_PERMISSION = "terminatorplus.manage";
+
+    public CommandInstance(CommandHandler handler, String name, String description, @Nullable String... aliases) {
+        super(name, description, "", aliases == null ? new ArrayList<>() : Arrays.asList(aliases));
+
+        this.commandHandler = handler;
+        this.methods = new HashMap<>();
+    }
+
+    public Map<String, CommandMethod> getMethods() {
+        return methods;
+    }
+
+    protected void addMethod(String name, CommandMethod method) {
+        methods.put(name, method);
+    }
+
+    @Override
+    public boolean execute(@Nonnull CommandSender sender, @Nonnull String label, @Nonnull String[] args) {
+        if (!sender.hasPermission(MANAGE_PERMISSION)) {
+            return false;
+        }
+
+        CommandMethod method;
+
+        if (args.length == 0) {
+            method = methods.get("");
+        } else if (methods.containsKey(args[0])) {
+            method = methods.get(args[0]);
+        } else {
+            method = methods.get("");
+        }
+
+        if (method == null) {
+            sender.sendMessage(ChatColor.RED + "There is no root command present for the " + ChatColor.YELLOW + getName() + ChatColor.RED + " command.");
+            return true;
+        }
+
+        List<String> arguments = new ArrayList<>(Arrays.asList(args));
+
+        if (arguments.size() > 0) {
+            arguments.remove(0);
+        }
+
+        try {
+            method.getMethod().invoke(method.getHandler(), sender, arguments);
+        } catch (InvocationTargetException | IllegalAccessException e) {
+            sender.sendMessage(ChatColor.RED + "Failed to perform command.");
+            e.printStackTrace();
+        }
+
+        return true;
+    }
+
+    @Override
+    @Nonnull
+    @SuppressWarnings("unchecked")
+    public List<String> tabComplete(@Nonnull CommandSender sender, @Nonnull String label, @Nonnull String[] args) {
+        if (args.length == 1) {
+            return methods.keySet().stream().filter(c -> !c.isEmpty()).collect(Collectors.toList());
+        }
+
+        if (args.length > 1) {
+            CommandMethod commandMethod = methods.get(args[0]);
+            Method autofiller = commandMethod.getAutofiller();
+
+            if (autofiller != null) {
+                try {
+                    return (List<String>) autofiller.invoke(commandMethod.getHandler(), sender, args);
+                } catch (InvocationTargetException | IllegalAccessException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        return new ArrayList<>();
+    }
+}