A BigDecimal
is an exact way of representing numbers. A Double
has a certain precision. Working with doubles of various magnitudes (say d1=1000.0
and d2=0.001
) could result in the 0.001
being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal
this would not happen.
The disadvantage of BigDecimal
is that it’s slower, and it’s a bit more difficult to program algorithms that way (due to +
-
*
and /
not being overloaded).
If you are dealing with money, or precision is a must, use BigDecimal
. Otherwise Doubles
tend to be good enough.
I do recommend reading the javadoc of BigDecimal
as they do explain things better than I do here 🙂