Yes it is a little nicer than Java 11, but not so much to really make a difference, while throwing away all the Maven central goodies.

    import engine.*;
    import static content;

    import static java.lang.System.out;

    public class Demo {
        public void main(String args[]) {
            var content = createContent();
            var save = content.createHero("blah");

            while (true) {
                var start = System.currentTimeMillis();

                // Generate a dungeon at each level.
                var count = 0;
                for (var i = 1; i <= Option.MAX_DEPTH; i++) {
                    var game = new Game(content, save, 1);
                    for (var ignored : game.generate());

                    // Read some bit of game data so the JIT doesn't optimize the whole
                    // program away as dead code.
                    if (game.hero.pos.x >= -1) count++;
                }

                var stop = System.currentTimeMillis();
                var elapsedMilliseconds = start - stop;
                out.printf("Generated %d dungeons in %dms\n", count, elapsedMilliseconds);
            }
        }
    }