Hi,

To format number in Java you can use the class java.text.NumberFormat.

Here is simple examples:

NumberFormat numberFormat = NumberFormat.getInstance();
 // setting number after decimal places
numberFormat.setMinimumFractionDigits(3);
numberFormat.setMaximumFractionDigits(3);        
 // from integer to String
String formatNumber = numberFormat.format(1234);

Check full source code at NumberFormat In Java.

Thanks