Help Round decimal 2 palces

Question

I have searched, but I cannot seem to find an answer to my question.
I am a student in into to programing and I am trying to figure out why my decimals will not round. I have tried everything I can find, but being new to java programing, I am sure I am making a syntatical error somewhere. My program works other than not displaying the decimal places the way I want, 200.00 not 200.0.
The following is my code, I have commented out each of the decimal formats I have tried.
import javax.swing.JOptionPane;
import java.text.DecimalFormat;
import java.text.NumberFormat;
public class CheckingAcct
     //int decimalPlaces = 2;
// Truncates the big decimal value.
//bd = bd.setScale(decimalPlaces, BigDecimal.ROUND_DOWN);
     //String string = bd.toString();
          //DecimalFormat df = new DecimalFormat ( "0.0#" );
               //DecimalFormat twoDigits = new DecimalFormat ( "0.0#" );
          //DecimalFormat decimalFormat = (DecimalFormat)numberFormat;
          //decimalFormat.applyPattern("0.0#");
     public static void main (String args[])
          String strBalance,
               strDeposit,
               strChecks;
          double balance = 200.00,
          deposit,
               lbcharge = 2.00,
               nsfcharge = 25.00,
               checks;
          //Display Starting Balance
          JOptionPane.showMessageDialog (null, "Your current balance is:$" + balance);
          //calculate balance
     strDeposit = JOptionPane.showInputDialog ("Please enter your deposit amount:$");
     deposit = Double.parseDouble (strDeposit);
     balance = deposit + balance;
     JOptionPane.showMessageDialog (null, "Your current balance after deposit is:$" + balance);
     strChecks = JOptionPane.showInputDialog ("Please enter the total amount of checks written:$");
     checks = Double.parseDouble (strChecks);
     balance = balance - checks;
     //Low Balance
     if (balance < 100.00)
          JOptionPane.showMessageDialog (null, "You have fallen below the minium required balance and you have been charged:$" + lbcharge);     
               balance = balance - lbcharge;
          else
               lbcharge = 0.00;
          //NSF Charge
     if (balance <= 0.00)
          JOptionPane.showMessageDialog (null, "You have a negative balance and you have been charged:$" + nsfcharge);     
               balance = (balance - nsfcharge);
          JOptionPane.showMessageDialog (null, "Your current balance is:$" + balance);     
          else
          JOptionPane.showMessageDialog (null, "Your balance is:$" + balance);
     System.exit (0);
}

Answer 1

I tend to use super class NumberFormat, because I can
never remember the jiggery-pokery of those patterns:
import java.text.*;
public class Example {
public static void main(String[] args) {
NumberFormat fmt = NumberFormat.getInstance();
fmt.setMinimumFractionDigits(2);
fmt.setMaximumFractionDigits(2);
System.out.println(fmt.format(200.0));
System.out.println(fmt.format(200.115));
System.out.println(fmt.format(200.125));
}Just be aware that NumberFormat/DecimalFormat uses
half-even rounding.This confirms another thought I had, that I must format each number I want to use. Thank you.