Rounding BigDecimal to *always* have two decimal places

Question

I'm trying to round BigDecimal values up, to two decimal places.

I'm using

BigDecimal rounded = value.round(new MathContext(2, RoundingMode.CEILING));
logger.trace("rounded {} to {}", value, rounded);

but it doesn't do what I want consistently:

rounded 0.819 to 0.82
rounded 1.092 to 1.1
rounded 1.365 to 1.4 // should be 1.37
rounded 2.730 to 2.8 // should be 2.74
rounded 0.819 to 0.82

I don't care about significant digits, I just want two decimal places. How do I do this with BigDecimal? Or is there another class/library better suited to this?

Solution

value = value.setScale(2, RoundingMode.CEILING)

Comments

[Gilbert Le Blanc]

If you actually want to round, you would use RoundingMode.HALF_UP

[Brad Mace]

That does indeed work how I want. Is the difference simply that round() works with significant digits while setScale works with a fixed number of decimal places or is there more to it?

[Grzegorz Dev]

Use RoundingMode.HALF_UP to do "typcal rounding". That is 1.111 gives 1.11 [CEILING gives 1.12]

[silver]

Thanks for RoundingMode.HALF_UP. As per documentation it is the rounding method commonly taught in schools - what I needed.

[Dale]

Take care if your values can be negative as in an accounting application. You may need to use RoundingMode.UP instead of CEILING

[Jason Law]

Why does setScale(...) work? see BigDecimal setScale and round.