Random number wrapper class
That does look a little confusing.  The example you looked at is for C, not Java.  I would do this:

int random = (int) Math.floor(Math.random() * (max - min + 1) ) + min;


It works like this:  Math.random() returns a double between 0 and 1 (although never actually equal to 1).  The full range of values you want is (max - min + 1) (the +1 is because you probably want max to min inclusive), so this will scale the number over the correct number of integer values.  We floor it (round down) because we want an int, and finally shift it upwards by adding min to put the numbers in the correct range.  We also cast to an int since we don't want it as a double.

EDIT: On further inspection, this is better; no casting and rounding of doubles:

Random rand = new Random();
int random = rand.nextInt(max - min + 1) + min;