Round half even for double

Question

I need to round to nearest 0.5 if possible.

10.4999 = 10.5

Here is quick code:

import java.text.DecimalFormat;
import java.math.RoundingMode;         


        

Answer 1

Rather than try rounding to the nearest 0.5, double it, round to the nearest int, then divide by two.

This way, 2.49 becomes 4.98, rounds to 5, becomes 2.5.
2.24 becomes 4.48, rounds to 4, becomes 2.