formatting a string in java

Question

I would like to know how to provide a formatting capabilities that enable the user to specify the number of digits of precision to the right of a decimal number. so instead of using the classical formatting .2f or .3f etc.. I want the user to be able to enter the precision of the decimal number.

i have a code written as follows

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Scanner input = new Scanner (System.in);
int precision = input.nextInt();

addNumbers.numberRepresentaiton(int precision);

The method is defined as below

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private String numberRepresentation(int precision)
{
    return String.format("%.precisionf", add);
}

executing the above results in conversion formatting error. Thank you for your time.

Answer 1

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private String numberRepresentation(int precision)
{
    return String.format("%." + precision + "f", add);
}

You have to concatenate the format string - the Formatter can't detect the variable name automagically ;)

Answer 2

Use:

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return String.format("%." + precision + "f", add);