This is a small Java-Project with JDA that returns a Discord-User's name in exchange of his ID.
THIS PROBABLY DOES NOT WORK ANYMORE BECAUSE DISCORD IMPROVED PRIVACY
In order to run it, just set the environment variable BOT_TOKEN to your Application token and you are good to go.
Execute the binary with java (written with JDK 11) or in intellij and paste your id into the Console and hit <enter> after the it is online.