Uhh… it… java containers? Umm… You’ve got me! I don’t know!
You sound like you mean what’s it about, so here’s the about page:
https://itch.io/docs/general/about
If i’m way off, my next hope is that the Getting Started page is exactly the thing you’re after:
https://itch.io/docs/creators/getting-started
If that fails, i’ve failed you.