Date and currency in business apps

Question

Last year, I was concerned about the difficulty to use java.util.Date class in business applications.
See thread "Date is a mess for business use" at http://forum.java.sun.com/thread.jsp?forum=4&thread=464726
And yes, I continue to think that a Date with 61 seconds in a minute is unusable in a business environment !
We need to store business dates, not timestamps.
Working for an insurance company, suitable date and currency classes are of paramount importance, but Java doesn't include such classes, rendering its use very difficult, not to say almost impossible.
I just give here a pointer to some very interesting articles I just came across lately.
I think it can be of some help to people facing the same problems as me about Date and currency storage.
http://www.idinews.com/darkside.pdf
http://www.idinews.com/freeware.html
http://www.idinews.com/sourcecode/DateJava.html
http://www.idinews.com/sourcecode/MoneyJava.html
At last, with these two classes, we can do the same data processing as we did with all our cobol programs.
Happy reading !

Answer 1

I tried using the Money class on the compound interest example from http://www.cs.princeton.edu/introcs/91float/. Here's my code:
Money deposit = new Money(1000d);
System.out.println("Deposit = "+deposit);
System.out.println("Double precision interest = "+
     deposit.mpy(Math.pow(1 + .05 / 365, 365)));
Money dailyAmount = new Money(deposit);
for (int i = 0; i < 365; i++)
          dailyAmount = dailyAmount.mpy (1 + .05 / 365);
System.out.println("Daily calculated interest = "+dailyAmount);The output looks like:
Deposit = $1,000.00
Double precision interest = $1,051.26
Daily calculated interest = $1,049.40But the second value should be $1,051.27. Because Money uses a long to represent the amount I end up missing a penny when double precision rounding is applied, and because it rounds down I end up missing almost $2 when the amount is calculated daily.