Added Tab complete for command

.gitignore

@@ -1,2 +1,5 @@
 /target/
 /dependency-reduced-pom.xml
+.idea
+/out/
+/InventoryRollback.iml

src/main/java/me/danjono/inventoryrollback/InventoryRollback.java

@@ -10,6 +10,7 @@
 
 import me.danjono.inventoryrollback.UpdateChecker.UpdateResult;
 import me.danjono.inventoryrollback.commands.Commands;
+import me.danjono.inventoryrollback.commands.CommandsTab;
 import me.danjono.inventoryrollback.config.ConfigFile;
 import me.danjono.inventoryrollback.listeners.ClickGUI;
 import me.danjono.inventoryrollback.listeners.EventLogs;
@@ -50,6 +51,7 @@ public void onEnable() {
             bStats();
 
         this.getCommand("inventoryrollback").setExecutor(new Commands());
+        this.getCommand("inventoryrollback").setTabCompleter(new CommandsTab());
 
         this.getServer().getPluginManager().registerEvents(new ClickGUI(), instance);
         this.getServer().getPluginManager().registerEvents(new EventLogs(), instance);

src/main/java/me/danjono/inventoryrollback/commands/CommandsTab.java

@@ -0,0 +1,38 @@
+package me.danjono.inventoryrollback.commands;
+
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabCompleter;
+
+import me.danjono.inventoryrollback.config.ConfigFile;
+import org.bukkit.entity.Player;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class CommandsTab extends ConfigFile implements TabCompleter {
+    @Override
+    public List<String> onTabComplete(CommandSender sender, Command command, String alias, String[] args) {
+        List<String> cmdlist = new ArrayList<String>();
+        if (args.length == 1) {
+            if (sender.hasPermission("inventoryrollback.restore") && sender instanceof Player) {
+                cmdlist.add("restore");
+            }
+            if (sender.hasPermission("inventoryrollback.forcebackup")) {
+                cmdlist.add("forcebackup");
+            }
+            if (sender.hasPermission("InventoryRollback.enable")) {
+                cmdlist.add("enable");
+            }
+            if (sender.hasPermission("InventoryRollback.disable")) {
+                cmdlist.add("disable");
+            }
+            if (sender.hasPermission("InventoryRollback.reload")) {
+                cmdlist.add("reload");
+            }
+        } else {
+            return null;
+        }
+        return cmdlist;
+    }
+}