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javanumber-formatting

NumberFormat setMaximumFractionDigits method

I am trying out the methods and the functionality of the class NumberFormat and I have reached to a strange result. I compile and run the following program:

public static void main(String[] args) {

Locale loc = Locale.US;
    NumberFormat nf = NumberFormat.getInstance(loc);
    System.out.println("Max: "+nf.getMaximumFractionDigits());
    System.out.println("Min: "+nf.getMinimumFractionDigits());
    try {
        Number d = nf.parse("4527.9997539");
        System.out.println(d);
        // nf.setMaximumFractionDigits(4);
        System.out.println(nf.format(4527.999753));
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

The output is:

Max: 3
Min: 0
4527.9997539
4,528

That means that it does not take into account any fraction digit. If I uncomment the line:

nf.setMaximumFractionDigits(4);

the output is:

Max: 3
Min: 0
4527.9997539
4,527.9998

In other words it works OK. What is actually happening with method setMaximumFractionDigits() and it does not bring the number containing 3 fraction digits in the first case?

Solution

  • I found the answer finally. The method setMaximumFractionDigits() has an effect only on the method format(). It has nothing to do with parse(). In my code fragment I use the method format() after setting manually the number of fraction digits to 4, consequently it affects the result.