Representing money
Avoid basic style errors
float and double (and
the corresponding wrapper classes
Float and
Double)
should likely be avoided. The fundamental problem is that rounding errors will always occur when using these data types -
they are unavoidable.
In a typical business application, using float and double to represent money values is
dangerous, because of these rounding issues. Instead,
BigDecimal
should usually be used to represent money.
From an IBM article on this topic:
"...binary floating-point arithmetic should not be used for financial, commercial, and user-centric applications or web services because the decimal data used in these applications cannot be represented exactly using binary floating-point."
From an article by Brian Goetz:
"...it is a bad idea to use floating point to try to represent
exact quantities like monetary amounts. Using floating point for dollars-and-cents calculations is a
recipe for disaster. Floating point numbers are best reserved for values such as measurements, whose
values are fundamentally inexact to begin with."