Serialize a Double to 2 decimal places using Jackson

I know that Double should not be used as a monetary amount. However,
this is not my code.

Indeed, it should not. BigDecimal is a much better choice for storing monetary amounts because it is lossless and provides more control of the decimal places.

So for people who do have control over the code, it can be used like this:

double amount = 111.222;
setAmount(new BigDecimal(amount).setScale(2, BigDecimal.ROUND_HALF_UP));

That will serialize as 111.22. No custom serializers needed.