How to format long numbers?

Question

If I have a number that is 100,000,000 how can I represent that as "100M" in a string?

Answer 1

To my knowledge there's no library support for abbreviating numbers, but you can easily do it yourself:

NumberFormat formatter = NumberFormat.getInstance();
String result = null;
if (num % 1000000 == 0 && num != 0) {
   result = formatter.format(num / 1000000) + "M";
} else if (num % 1000 == 0 && num != 0) {
   result = formatter.format(num / 1000) + "K";
} else {
   result = formatter.format(num);
}

Of course, this assumes that you don't want to shorten a number like 1,234,567.89. If you do, then this question is a duplicate.