Minecraft classic was written in Java; it's quite cool to read Notch's early posts on this Java game dev forum that I found for random reasons this morning:
https://jvm-gaming.org/u/Markus_Persson
[To read just his posts click the MC thread... https://jvm-gaming.org/t/minecraft/33567 ... then his name, and then "32 posts in topic"]
May 18, 2009: "...The site where I'll put it: http://www.minecraft.net/"
May 20, 2009: "There's no actual gameplay yet. What you're playing there is "creative mode" where you just build a world."
June 10, 2009: "I released multiplayer the other day, and registrations shot through the roof. Over 24 hours, I got about 1200 registrations, and there currently are about 200 players playing it online. Holy moly!"
July 30, 2010: "A small game studio would be very nice in the long run, but for now I kind of enjoy being my own boss."
...
[https://minecraft.wiki/w/Java_Edition = timeline up to Full Editiok release. Crazy how fast something can blow up like that eh?]
To quote Andy Samberg, *BELIEVE IN YOUR DREAMS*.
I didn't find my way into the game until 2011 but man what a journey it has been since then.