MinecraftOfflineOnlineConverter v3

Ever started playing on one of your Minecraft servers and a few hours later that one friend that didn't buy the game wants to join? Now you have to start a lengthy process of turning your server to offline mode and making sure everyone has their inventory and achievements after the switch...

This happened to me way to often, and now I automated the whole process. The Java applicatin will convert all player related files to be offline or online compatible.

Supporting

Currently I tested and can confirm support for Vanilla, Bukkit, Paper and Purpur servers. Every Minecraft version since and including 1.17.1 is confirmed to work. Earlier versions I can't guarantee.

Regarding Spigot and Forge servers, I haven't had enough time to fully confirm everything will work 100% of the time. But using the new custom_paths.yml file, you can specify custom directories to convert.

Usage

First look at Disclaimer and make sure you understand the "risks" of using this tool.

• Obviously download the jar

• Place it in your server's main folder (not mandatory, just makes things easier)

• Optional: Rename TEMPLATE.custom_paths.yml to custom_paths.yml and use the examples presented to define custom directories you want to convert

• Execute the jar through your terminal with the following command:

java -jar MinecraftOfflineOnlineConverter_3.jar <arguments>

• You will have to pass one of these arguments
  • -offline to convert your server to offline files
  • -online to convert your server to online files
• If necessary -p "path/to/server/folder/" (if the jar is not in the server's main folder)
• -v for verbose output
• -h for help

Known Issues

• Paper servers (when converted to offline), sometimes create <Online UUID>.dat.offline-read) files.
• No full support for Spigot, Sponge and Forge servers.

TODOs

• Ensure anything to do with files and directories is not done via Strings - done..ish
• Cleanup spaghetti code
• Cleanup outputs/logging

Building

Execute the command

mvn clean compile assembly:single

to build a JAR file of the project with all dependencies.

Disclaimer

Please always make a backup of your game files before using this tool. Whilst it was thoroughly tested on my own servers, there is always the chance that a bug might occur!

If you need this application for a lower Minecraft and/or Java version, please leave me a message or issue :)!

License

This project is licensed under the MIT License.

Remark

Minecraft is a registered trademark of Mojang AB.