Specifying Precision : Number Format « Data Type « Java Tutorial

A precision specifier can be applied to the %f, %e, %g, and %s format specifiers.

When applying to floating-point data using the %f, %e, or %g specifiers, it determines the number of decimal places displayed.

The default precision is 6.

For example, %10.4f displays a number at least ten characters wide with four decimal places.

import java.util.Formatter;

public class MainClass {
  public static void main(String args[]) {
    Formatter fmt;

    fmt = new Formatter();

    fmt.format("%1.4f", 1234567890.123456789);

2.14.Number Format
2.14.1.Number formatting helps make your numbers more readable.
2.14.2.Specifying Precision
2.14.3.Applied to strings, the precision specifier specifies the maximum field length
2.14.4.Illustrating the precision specifier
2.14.5.Add leading zeros to a number
2.14.8.NumberFormat: Minimum Integer Digits, Maximum/Minimum Fraction Digits
2.14.9.Number format with FieldPosition
2.14.11.A number formatter for logarithmic values. This formatter does not support parsing.
2.14.12.Format a percentage for presentation to the user
2.14.13.Get Percent Value
2.14.14.Helper class for format number and currency