You probably don't want the (int start) in your constructor. Or if you do, at least give it a different name to your private field.
When you make a new array, you need to specify its dimensions, as inYou will find it's already full of zeros, because 0 is the default for an int.
If you wanted to put other numbers in, you could use Arrays.fill(). But you would have to loop over the arrays because in Java, there's no such thing as multi-dimensional arrays, only arrays of arrays.