Я пишу игру отдельно от javarush. нужна помощь с генерацией мира.

public class WorldGenerator {

    private final Random random = new Random();
    private final Tile[][] world;

    public WorldGenerator(int width, int height) {
        world = new Tile[height][width];
        init();
    }

    private void init() {
        for (int i = 0; i < world.length; i++) {
            for (int j = 0; j < world[i].length; j++) {
                world[i][j] = new Tile(getRandomType());
            }
        }
    }

    private Type getRandomType() {
        Type[] types = Type.values();
        return types[random.nextInt(types.length)];
    }

    public void print() {
        for (Tile[] tiles : world) {
            for (Tile tile : tiles) {
                System.out.print(tile);
            }
            System.out.println();
        }
    }

    public static void main(String[] args) {
        WorldGenerator generator = new WorldGenerator(5, 5);
        generator.print();
    }

    public static class Tile {
        private final Type type;

        public Tile(Type type) {
            this.type = type;
        }

        @Override
        public String toString() {
            return String.format(" %s ", type.name());
        }
    }

    enum Type {
        NULL,
        DIRT,
        WATER,
        SAND,
        STONE
    }
}