How do I deserialize the Minecraft player.dat?

Question

I'm trying to make a plugin for Velocity to sync player data among different sub servers.

I want to deserialize the player.dat which is saved in the /world/playerdata/ directory, then upload ut to MySQL. When a player connect a different sub server, I'll read the data in MySQL and send the data to the targeted sub server to make the player data synchronous.

Answer 1

It's solved by myself.

We can use NBTCompressedStreamTools, which you need to know about NMS, like this

File playerDataFolder = new File(getDataFolder().getParentFile().getParentFile(), "world\\playerdata\\");
File playerDat = new File(playerDataFolder, player.getUniqueId().toString() + ".dat");
try {
    FileInputStream inputStream = new FileInputStream(playerDat);
    NBTTagCompound nbt = NBTCompressedStreamTools.a(inputStream);
}catch (Exception e) {
    e.printStackTrace();
}