/** BankAccount class, version 1 * Anderson, Franceschi * Represents a generic bank account */ import java.text.DecimalFormat;

public class BankAccount { public final DecimalFormat MONEY = new DecimalFormat( "$#,##0.00" ); private double balance;

/** Default constructor * sets balance to 0.0 */ public BankAccount( ) { balance = 0.0; System.out.println( "In BankAccount default constructor" ); }

/** Overloaded constructor * @param startBalance beginning balance */ public BankAccount( double startBalance ) { deposit( startBalance ); System.out.println( "In BankAccount overloaded constructor" ); }

/** Accessor for balance * @return current account balance */ public double getBalance( ) { return balance; }

/** Deposit amount to account * @param amount amount to deposit; * amount must be >= 0.0 */ public void deposit( double amount ) { if ( amount >= 0.0 ) balance += amount; else System.err.println( "Deposit amount must be positive." ); }

/** withdraw amount from account * @param amount amount to withdraw; * amount must be >= 0.0 * amount must be <= balance */ public void withdraw( double amount ) { if ( amount >= 0.0 && amount <= balance ) balance -= amount; else System.err.println( "Withdrawal amount must be positive " + "and cannot be greater than balance" ); }

/** toString * @return the balance formatted as money */ public String toString( ) { return ( "balance is " + MONEY.format( balance ) ); } }

/* SavingsAccount class Anderson, Franceschi */

import java.text.NumberFormat;

// 1. ***** indicate that SavingsAccount inherits // from BankAccount public class SavingsAccount {

public final double DEFAULT_RATE = .03;

// 2. ****** define the private interestRate instance variable // interestRate, a double, represents an annual rate // Part 2 student code starts here:

// Part 2 student code ends here.

// 3 ***** write the default constructor /** default constructor * explicitly calls the BankAccount default constructor * set interestRate to default value DEFAULT_RATE * print a message to System.out indicating that * constructor is called */ // Part 3 student code starts here:

// Part 3 student code ends here.

// 4 ***** write the overloaded constructor /** overloaded constructor * explicitly call BankAccount overloaded constructor * call setInterestRate method, passing startInterestRate * print a message to System.out indicating that * constructor is called * @param startBalance starting balance * @param startInterestRate starting interest rate */ // Part 4 student code starts here:

// Part 4 student code ends here.

// 5 ****** write this method: /** applyInterest method, no parameters, void return value * call deposit method, passing a month's worth of interest * remember that interestRate instance variable is annual rate */ // Part 5 student code starts here:

// Part 5 student code ends here.

/** accessor method for interestRate * @return interestRate */ public double getInterestRate() { return interestRate; }

/** mutator method for interestRate * @param newInterestRate new value for interestRate * newInterestRate must be >= 0.0 * if not, print an error message */ public void setInterestRate(double newInterestRate) { if (newInterestRate >= 0.0) { interestRate = newInterestRate; } else { System.err.println("Interest rate cannot be negative"); } }

// 6 ***** write this method /* toString method * @return String containing formatted balance and interestRate * invokes superclass toString to format balance * formats interestRate as percent using a NumberFormat object * To create a NumberFormat object for formatting percentages * use the getPercentInstance method in the NumberFormat class, * which has this API: * static NumberFormat getPercentInstance( ) */ // Part 6 student code starts here:

// Part 6 student code ends here.

}

/* Teller class for exercising the SavingsAccount class * Anderson, Franceschi */

import java.awt.*; import java.awt.event.*; import javax.swing.*; import java.text.*;

public class Teller extends JFrame { private JButton changeRate, applyInterest, deposit, withdraw, accountInfo, exit; private JTextArea ledgerActivity, ledgerBalance, ledgerRate; private String lActivity, lBalance, lRate; private double rate, balance, amount; private NumberFormat currency, percent; private static SavingsAccount s1; private JPanel buttonPanel, ledgerPanel;

public Teller( ) { super( "Savings Account Ledger" ); Container cp = getContentPane( );

buttonPanel = new JPanel( ); buttonPanel.setLayout( new FlowLayout( ) );

changeRate = new JButton( "Change interest rate" ); buttonPanel.add( changeRate ); ButtonHandler bh = new ButtonHandler( ); changeRate.addActionListener( bh );

applyInterest = new JButton( "Apply interest" ); buttonPanel.add( applyInterest ); applyInterest.addActionListener( bh );

deposit = new JButton( "Deposit" ); buttonPanel.add( deposit ); deposit.addActionListener( bh );

withdraw = new JButton( "Withdraw" ); buttonPanel.add( withdraw ); withdraw.addActionListener( bh );

accountInfo = new JButton( "Display Account Information" ); buttonPanel.add( accountInfo ); accountInfo.addActionListener( bh );

exit = new JButton( "Exit" ); buttonPanel.add( exit ); exit.addActionListener( new ActionListener( ) { public void actionPerformed( ActionEvent e ) { System.exit( 0 ); } } );

ledgerPanel = new JPanel( ); ledgerPanel.setLayout( new GridLayout( 1, 3 ) );

ledgerActivity = new JTextArea( ); lActivity = "ACTIVITY "; lActivity += "Account Opened "; ledgerActivity.setText( lActivity ); ledgerActivity.setEditable( false ); ledgerPanel.add( ledgerActivity );

currency = NumberFormat.getCurrencyInstance( ); ledgerBalance = new JTextArea( ); lBalance = "BALANCE "; lBalance += currency.format( s1.getBalance( ) ) + " "; ledgerBalance.setText( lBalance ); ledgerBalance.setEditable( false ); ledgerPanel.add( ledgerBalance );

percent = NumberFormat.getPercentInstance( ); ledgerRate = new JTextArea( ); lRate = "INTEREST RATE "; lRate += percent.format( s1.getInterestRate( ) ) + " "; ledgerRate.setText( lRate ); ledgerRate.setEditable( false ); ledgerPanel.add( ledgerRate );

cp.setLayout( new GridLayout( 2, 1 ) ); cp.add( buttonPanel ); cp.add( ledgerPanel );

setSize( 300, 350 ); setVisible( true ); }

private class ButtonHandler implements ActionListener { public void actionPerformed( ActionEvent e ) { if ( e.getSource( ) == accountInfo ) { JOptionPane.showMessageDialog( null, s1, "Account Information", JOptionPane.INFORMATION_MESSAGE ); } else { if ( e.getSource( ) == changeRate ) { rate = getInput( "new interest rate (Ex: .05 is 5%)" ); s1.setInterestRate( rate ); lActivity += "Rate changed "; } else if ( e.getSource( ) == applyInterest ) { s1.applyInterest( ); lActivity += "Interest applied "; } else if ( e.getSource( ) == deposit ) { amount = getInput( "amount to deposit" ); s1.deposit( amount ); lActivity += "Deposit "; } else if ( e.getSource( ) == withdraw ) { amount = getInput( "amount to withdraw" ); s1.withdraw( amount ); lActivity += "Withdrawal "; }

lBalance += currency.format( s1.getBalance( ) ) + " "; lRate += percent.format( s1.getInterestRate( ) ) + " "; ledgerActivity.setText( lActivity ); ledgerBalance.setText( lBalance ); ledgerRate.setText( lRate ); repaint( ); } } }

public double getInput( String inputItem ) { double amount = 0.0; String input = ""; boolean badInput = true; do { input = JOptionPane.showInputDialog( "Enter the " + inputItem ); if ( input != null ) { try { amount = Double.parseDouble( input ); badInput = false; } catch ( NumberFormatException nfe ) { badInput = true; JOptionPane.showMessageDialog( null, inputItem + " must be numeric", "Input error", JOptionPane.ERROR_MESSAGE ); } } }while ( badInput == true ); return amount; }

public static void main( String [] args ) { double balance = 0.0, rate = 0.0; String input = "";

boolean badBalance = true; boolean defaultObj = false;

do { input = JOptionPane.showInputDialog( "Enter the starting balance;" + " or press return to use the default constructor" );

if ( input == null ) { System.exit( 0 ); } else if ( input.length( ) == 0 ) { s1 = new SavingsAccount( ); // use default constructor badBalance = false; defaultObj = true; } else { try { balance = Double.parseDouble( input ); if ( balance < 0.0 ) JOptionPane.showMessageDialog( null, "Balance cannot be negative" ); else badBalance = false; } catch ( NumberFormatException e ) { JOptionPane.showMessageDialog( null, "Balance must be a number" ); } } }while ( badBalance );

if ( ! defaultObj ) { boolean badRate = true; do { try { input = JOptionPane.showInputDialog( "Enter the interest rate (for example .05 is 5%)" ); if ( input != null ) { rate = Double.parseDouble( input ); if ( rate < 0.0 ) JOptionPane.showMessageDialog( null, "Interest rate cannot be negative" ); else badRate = false; } else System.exit( 0 ); } catch ( NumberFormatException e ) { JOptionPane.showMessageDialog( null, "Interest rate must be a number" ); } }while ( badRate ); s1 = new SavingsAccount( balance, rate ); }

Teller app = new Teller( ); app.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ); } }