Question

This is what I did to round a double to 2 decimal places:

amount = roundTwoDecimals(amount);

public double roundTwoDecimals(double d) {
    DecimalFormat twoDForm = new DecimalFormat("#.##");
    return Double.valueOf(twoDForm.format(d));
}

This works great if the amount = 25.3569 or something like that, but if the amount = 25.00 or the amount = 25.0, then I get 25.0! What I want is both rounding as well as formatting to 2 decimal places.

Answer 1

Are you working with money? Creating a String and then converting it back is pretty loopy.

Use BigDecimal. This has been discussed quite extensively. You should have a Money class and the amount should be a BigDecimal.

Even if you’re not working with money, consider BigDecimal.