Formatting prices with two decimals

The NumberFormat class helps you to format and parse numbers or currency values. Since it's an abstract class you must call the getInstance() method or some variation of that method.

myString = NumberFormat.getInstance().format(myNumber);

Formatting prices with two decimal places

You can use the NumberFormat class from the Java API

NumberFormat nf = NumberFormat.getInstance();
nf.setMaximumFractionDigits(2);
nf.setMinimumFractionDigits(2);
setRoundingMode(RoundingMode.HALF_UP);

System.out.print(nf.format(decimalNumber));

Or you can use String.format. This will also work with printf to print a formatted string.

double myDouble = 3.5;
String formattedData = String.format("%.02f",myDouble);