DecimalFormat Objects

The program creates a DecimalFormat object. The format() method of this object converts a number into a StringBuffer. A StringBuffer is almost the same as a String except it can be modified. No modification of a StringBuffer will be done in this chapter, so it will be treated exactly as if it were a String.

To utilize the DecimalFormat object, you need to import java.text.*; and set up a DecimalFormat constructor. Here is a complete program.

import java.text.*;

class IODemo2
{
  public static void main ( String[] args )
  {
    int value = 123456789 ;
    
    DecimalFormat decform = new DecimalFormat("000,000,000");   
    System.out.println( "value = " + decform.format(value) );
  }
}

The program uses the behavior of DecimalFormat.format(). Later you will see methods that further affect the output of format().