Nebula Alpha

A server mod for Minecraft Alpha 1.0.15, inspired by hey0's hMod and Llamacraft.

Nebula patches the original server JAR using ASM bytecode transformation to inject hooks for plugins, commands, anti-grief, and permissions — without modifying the original source code.

Features

• Plugin API — Load plugins from JAR files with event listeners and commands
• Event System — Cancellable events: chat, join, quit, block break/place, server tick
• Command System — Extensible command registry with permissions and aliases
• Anti-Grief — Configurable protection: disable TNT, fire, lava; spawn protection radius
• Permissions — Group-based permission system with colored prefixes
• Built-in Commands — /help, /kick, /ban, /tp, /give, /list, /setrank, /antigrief, /stop, /say, /home, /msg

Requirements

• Java 8 JDK (e.g., Amazon Corretto 8). Make sure your JAVA_HOME environment variable is set to your JDK 8 installation directory.
• Minecraft Alpha 1.0.15 server JAR (a0.1.0.jar)

Setup

1. Build the patcher:

   gradlew fatJar
   

   This produces build/libs/nebula-alpha.jar.

2. Create a server directory and place both files:

   server/
   ├── a0.1.0.jar          (original Alpha server)
   └── nebula-alpha.jar     (Nebula patcher)
   

3. Run the patcher:

   java -jar nebula-alpha.jar
   

   This creates server-nebula.jar — the patched server.

4. Launch the patched server:

   java -jar server-nebula.jar
   

   Or use auto-launch:

   java -jar nebula-alpha.jar --launch
   

Configuration

On first run, Nebula creates nebula.json:

Note: Minecraft uses the § character for color codes. You can customize prefixes and messages with these codes.

{
  "antiGriefEnabled": true,
  "disableFire": true,
  "disableTNT": true,
  "disableLavaGrief": true,
  "spawnProtectionRadius": 16,
  "maxPlayers": 20,
  "motd": "Welcome to Nebula Alpha!",
  "announceJoinQuit": true,
  "groups": {
    "admin": { "prefix": "[Admin]§f ", "permissions": ["*"] },
    "moderator": { "prefix": "[Mod]§f ", "permissions": ["nebula.kick", "nebula.ban", "nebula.tp", "nebula.give", "nebula.antigrief"] },
    "default": { "prefix": "", "permissions": ["nebula.home", "nebula.list", "nebula.help"] }
  },
  "bannedPlayers": [],
  "bannedIPs": [],
  "ops": []
}

Commands

Command	Permission	Description
/help	—	Show available commands
/list	—	List online players
/home	—	Teleport to spawn
/msg <player> <message>	—	Private message
/kick <player> [reason]	nebula.kick	Kick a player
/ban <player>	nebula.ban	Ban/unban a player
/tp <player> or /tp <x> <y> <z>	nebula.tp	Teleport
/give <player> <id> [amount]	nebula.give	Give items
/setrank <player> <group>	nebula.setrank	Set permission group
/antigrief [fire|tnt|lava|all] [on|off]	nebula.antigrief	Toggle anti-grief
/say <message>	nebula.say	Broadcast server message
/stop	nebula.stop	Stop the server

Writing Plugins

1. Create a JAR with a class extending dev.gura1.nebula.api.Plugin
2. Include a plugin.json in the JAR root:

   {
     "name": "MyPlugin",
     "version": "1.0",
     "main": "com.example.MyPlugin"
   }

3. Place the JAR in the plugins/ directory

Example Plugin

import dev.gura1.nebula.Nebula;
import dev.gura1.nebula.api.Plugin;
import dev.gura1.nebula.api.event.*;

public class MyPlugin extends Plugin {
    @Override
    public void onEnable() {
        getLogger().info("MyPlugin enabled!");
        Nebula.getInstance().getEventBus().register(this);
    }

    @EventHandler
    public void onChat(PlayerChatEvent event) {
        if (event.getMessage().contains("hello")) {
            event.getPlayer().sendMessage("§aHello there!");
        }
    }

    @Override
    public void onDisable() {
        getLogger().info("MyPlugin disabled!");
    }
}

Architecture

nebula-alpha.jar (patcher)
  ├── NebulaPatcher         — Reads server JAR, applies ASM transforms, injects Nebula classes
  ├── ASM Transformers      — Inject hooks into MinecraftServer, hm (player handler), fg (player manager)
  ├── NebulaHooks           — Default-package bridge between obfuscated classes and Nebula
  ├── Nebula                — Main singleton: events, commands, plugins, config, permissions
  ├── Event System          — EventBus, Event, Cancellable, @EventHandler
  ├── Command System        — CommandRegistry, CommandExecutor, @CommandInfo
  ├── Plugin API            — Plugin lifecycle, PluginLoader
  ├── Config                — NebulaConfig (JSON via Gson)
  ├── Permissions           — PermissionManager, PlayerData, group-based
  └── Anti-Grief            — AntiGriefManager (TNT, fire, lava, spawn protection)

License

MIT