src/me/teridax/jcash/Main.java

@@ -9,7 +9,6 @@ import javax.swing.*;
 public class Main {
 
     private static Main instance;
-
     private final JFrame window;
 
     private Main() {

src/me/teridax/jcash/banking/Account.java

@@ -9,7 +9,7 @@ public abstract class Account {
 
     private final int iban;
     private final int pin;
-    private final double balance;
+    private double balance;
 
     public Account(int iban, int pin, double balance) {
         this.iban = iban;
@@ -68,4 +68,17 @@ public abstract class Account {
     public String getDescription() {
         return String.format("%s (%s)", iban, getClass().getSimpleName());
     }
+
+    public void deposit(double amount) {
+        this.balance += amount;
+    }
+
+    @Override
+    public String toString() {
+        return String.format("@Account [iban=%d, pin=%d, balance=%.2f]", iban, pin, balance);
+    }
+
+    public void takeoff(double amount) {
+        this.balance = Math.max(0, this.balance - amount);
+    }
 }

src/me/teridax/jcash/banking/Bank.java

@@ -1,6 +1,7 @@
 package me.teridax.jcash.banking;
 
 import java.util.*;
+import java.util.regex.Pattern;
 
 @SuppressWarnings("unused")
 public final class Bank {
@@ -46,21 +47,20 @@ public final class Bank {
     }
 
     public static String validateBlz(String maybeBlz) {
-        var builder = new StringBuilder();
-        maybeBlz.trim().chars().filter(ch -> Character.isDigit(ch) || Character.isLetter(ch)).forEach(builder::append);
-        var blz = builder.toString();
+        var pattern = Pattern.compile("[\\w\\d-_]+");
+        var matcher = pattern.matcher(maybeBlz);
 
-        if (blz.isEmpty()) {
-            throw new IllegalArgumentException("Bank Blz must only contain letters and digits");
-        }
+        if (matcher.find())
+            return matcher.group();
 
-        return blz;
+        throw new IllegalArgumentException("not a valid BLZ: " + maybeBlz);
     }
 
     public Optional<Profile> getAccount(int iban) {
         for (var owner : this.accounts.entrySet()) {
             for (var account : owner.getValue()) {
-                if (account.getIban() == iban) {
+                var tmp = account.getIban();
+                if (tmp == iban) {
                     return Optional.of(new Profile(owner.getKey(), this, account, getAccountsOfOwner(owner.getKey())));
                 }
             }

src/me/teridax/jcash/banking/BankingManagementSystem.java

@@ -56,6 +56,6 @@ public final class BankingManagementSystem {
     }
 
     public Optional<Bank> getBank(String blz) {
-        return this.banks.stream().filter(b -> !b.getBlz().equals(blz)).findFirst();
+        return this.banks.stream().filter(b -> b.getBlz().equals(blz)).findFirst();
     }
 }

src/me/teridax/jcash/gui/account/AccountController.java

@@ -2,6 +2,9 @@ package me.teridax.jcash.gui.account;
 
 import me.teridax.jcash.Main;
 import me.teridax.jcash.banking.Profile;
+import me.teridax.jcash.gui.deposit.DepositDialog;
+import me.teridax.jcash.gui.takeoff.TakeoffDialog;
+import me.teridax.jcash.gui.transfer.TransferDialog;
 
 public class AccountController {
 
@@ -25,6 +28,18 @@ public class AccountController {
             Main.getInstance().logout();
             Main.getInstance().popLoginScreen();
         });
+
+        this.view.getDeposit().addActionListener(e -> {
+            new DepositDialog(profile.getPrimaryAccount(), () -> this.view.setProfile(profile));
+        });
+
+        this.view.getTakeoff().addActionListener(e -> {
+            new TakeoffDialog(profile.getPrimaryAccount(), () -> this.view.setProfile(profile));
+        });
+
+        this.view.getTransfer().addActionListener(e -> {
+            new TransferDialog(profile.getPrimaryAccount(), () -> this.view.setProfile(profile));
+        });
     }
 
     public AccountView getView() {

src/me/teridax/jcash/gui/deposit/DepositDialog.java

@@ -0,0 +1,17 @@
+package me.teridax.jcash.gui.deposit;
+
+import me.teridax.jcash.banking.Account;
+
+public class DepositDialog {
+
+    public DepositDialog(Account account, Runnable onDeposit) {
+        var view = new DepositView(account);
+        view.getDeposit().addActionListener(e -> {
+            account.deposit(view.getAmount());
+            onDeposit.run();
+            view.dispose();
+        });
+        view.getCancel().addActionListener(e -> view.dispose());
+        view.showDialog();
+    }
+}

src/me/teridax/jcash/gui/deposit/DepositView.java

@@ -0,0 +1,124 @@
+package me.teridax.jcash.gui.deposit;
+
+import me.teridax.jcash.banking.Account;
+
+import javax.swing.*;
+import javax.swing.text.NumberFormatter;
+import java.awt.*;
+import java.text.NumberFormat;
+import java.text.ParseException;
+import java.util.Locale;
+
+public class DepositView {
+
+    private JDialog dialog;
+    private JButton cancel;
+    private JButton deposit;
+    private JFormattedTextField value;
+
+    public DepositView(Account account) {
+        createComponents(account);
+        layoutComponents();
+    }
+
+    public void showDialog() {
+        dialog.setModalityType(Dialog.ModalityType.APPLICATION_MODAL);
+        dialog.setTitle("Deposit money");
+        dialog.pack();
+        dialog.setResizable(false);
+        dialog.setLocationRelativeTo(null);
+        dialog.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+        dialog.setVisible(true);
+    }
+
+    private NumberFormatter getNumberFormat() {
+        var format = NumberFormat.getNumberInstance(Locale.GERMANY);
+        format.setParseIntegerOnly(false);
+        format.setMaximumFractionDigits(2);
+
+        var formatter = new NumberFormatter(format);
+        formatter.setValueClass(Double.class);
+        formatter.setAllowsInvalid(false);
+
+        return formatter;
+    }
+
+    private void layoutComponents() {
+        dialog.getContentPane().setLayout(new GridBagLayout());
+
+        var c = new GridBagConstraints();
+        c.gridx = 0;
+        c.gridy = 0;
+        c.weightx = 1;
+        c.weighty = 1;
+        c.fill = GridBagConstraints.BOTH;
+        c.anchor = GridBagConstraints.CENTER;
+        c.insets = new Insets(10, 10, 10, 10);
+        dialog.getContentPane().add(new JLabel("Deposit money"), c);
+
+        c.gridx = 0;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(new JLabel("Betrag", SwingConstants.RIGHT), c);
+
+        c.gridx = 1;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(value, c);
+
+        c.gridx = 1;
+        c.gridy = 2;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(cancel, c);
+
+        c.gridx = 2;
+        c.gridy = 2;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(deposit, c);
+    }
+
+    private void createComponents(Account account) {
+        this.dialog = new JDialog();
+
+        this.cancel = new JButton("Abbrechen");
+        this.deposit = new JButton("Einzahlen");
+        this.value = new JFormattedTextField(getNumberFormat());
+
+        this.dialog.setContentPane(new JPanel(new GridBagLayout()));
+    }
+
+    public double getAmount() {
+        if (value.getText().isBlank())
+            return 0;
+
+        try {
+            return NumberFormat.getNumberInstance().parse(value.getText()).doubleValue();
+        } catch (ParseException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public JButton getCancel() {
+        return cancel;
+    }
+
+    public JButton getDeposit() {
+        return deposit;
+    }
+
+    public void dispose() {
+        this.dialog.dispose();
+    }
+}

src/me/teridax/jcash/gui/login/LoginController.java

@@ -1,6 +1,5 @@
 package me.teridax.jcash.gui.login;
 
-import me.teridax.jcash.banking.Account;
 import me.teridax.jcash.banking.BankingManagementSystem;
 
 import javax.swing.*;
@@ -9,8 +8,8 @@ import java.util.Optional;
 
 public class LoginController {
 
-    private LoginView view;
-    private LoginData data;
+    private final LoginView view;
+    private final LoginData data;
 
     private AccountSelectionListener listener;
 
@@ -33,6 +32,7 @@ public class LoginController {
             return Optional.empty();
         }
     }
+
     private Optional<Integer> getPin() {
         try {
             var iban = this.view.getPin().getPassword();

src/me/teridax/jcash/gui/login/LoginData.java

@@ -1,6 +1,5 @@
 package me.teridax.jcash.gui.login;
 
-import me.teridax.jcash.banking.Account;
 import me.teridax.jcash.banking.BankingManagementSystem;
 import me.teridax.jcash.banking.Profile;
 

src/me/teridax/jcash/gui/login/LoginView.java

@@ -1,18 +1,21 @@
 package me.teridax.jcash.gui.login;
 
 import javax.swing.*;
+import javax.swing.text.NumberFormatter;
 import java.awt.*;
+import java.text.NumberFormat;
 
 public class LoginView extends JPanel {
 
-    private final JTextField blz;
-    private final JTextField iban;
+    private final JFormattedTextField blz;
+    private final JFormattedTextField iban;
     private final JPasswordField pin;
     private final JButton login;
 
     public LoginView() {
-        this.blz = new JTextField("MA2424");
-        this.iban = new JTextField("4711");
+        this.blz = new JFormattedTextField("MA2424");
+        this.iban = new JFormattedTextField(getNumberFormat());
+        this.iban.setText("4711");
         this.pin = new JPasswordField("1234");
         this.login = new JButton("Login");
 
@@ -41,6 +44,19 @@ public class LoginView extends JPanel {
         content.add(login, constraints);
     }
 
+    private NumberFormatter getNumberFormat() {
+        var format = NumberFormat.getIntegerInstance();
+        format.setGroupingUsed(false);
+
+        var formatter = new NumberFormatter(format);
+        formatter.setValueClass(Integer.class);
+        formatter.setMinimum(0);
+        formatter.setMaximum(Integer.MAX_VALUE);
+        formatter.setAllowsInvalid(false);
+
+        return formatter;
+    }
+
     private void addInputRow(GridBagConstraints constraints, JComponent target, JComponent comp, int row, String name) {
         constraints.gridwidth = 1;
         constraints.gridx = 1;
@@ -71,5 +87,4 @@ public class LoginView extends JPanel {
     public JButton getLogin() {
         return login;
     }
-
 }

src/me/teridax/jcash/gui/takeoff/TakeoffDialog.java

@@ -0,0 +1,17 @@
+package me.teridax.jcash.gui.takeoff;
+
+import me.teridax.jcash.banking.Account;
+
+public class TakeoffDialog {
+
+    public TakeoffDialog(Account account, Runnable onDeposit) {
+        var view = new TakeoffView(account);
+        view.getDeposit().addActionListener(e -> {
+            account.takeoff(view.getAmount());
+            onDeposit.run();
+            view.dispose();
+        });
+        view.getCancel().addActionListener(e -> view.dispose());
+        view.showDialog();
+    }
+}

src/me/teridax/jcash/gui/takeoff/TakeoffView.java

@@ -0,0 +1,130 @@
+package me.teridax.jcash.gui.takeoff;
+
+import me.teridax.jcash.banking.Account;
+
+import javax.swing.*;
+import javax.swing.text.NumberFormatter;
+import java.awt.*;
+import java.text.NumberFormat;
+import java.text.ParseException;
+import java.util.Locale;
+
+import static javax.swing.JOptionPane.ERROR_MESSAGE;
+import static javax.swing.JOptionPane.showMessageDialog;
+
+public class TakeoffView {
+
+    private JDialog dialog;
+    private JButton cancel;
+    private JButton deposit;
+    private JFormattedTextField value;
+
+    public TakeoffView(Account account) {
+        createComponents(account);
+        layoutComponents();
+    }
+
+    public void showDialog() {
+        dialog.setModalityType(Dialog.ModalityType.APPLICATION_MODAL);
+        dialog.setTitle("Deposit money");
+        dialog.pack();
+        dialog.setResizable(false);
+        dialog.setLocationRelativeTo(null);
+        dialog.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+        dialog.setVisible(true);
+    }
+
+    private NumberFormatter getNumberFormat(double balance) {
+        var format = NumberFormat.getNumberInstance(Locale.GERMANY);
+        format.setParseIntegerOnly(false);
+        format.setMaximumFractionDigits(2);
+
+        var formatter = new NumberFormatter(format);
+        formatter.setValueClass(Double.class);
+        formatter.setAllowsInvalid(true);
+        formatter.setMaximum(balance);
+
+        return formatter;
+    }
+
+    private void layoutComponents() {
+        dialog.getContentPane().setLayout(new GridBagLayout());
+
+        var c = new GridBagConstraints();
+        c.gridx = 0;
+        c.gridy = 0;
+        c.weightx = 1;
+        c.weighty = 1;
+        c.fill = GridBagConstraints.BOTH;
+        c.anchor = GridBagConstraints.CENTER;
+        c.insets = new Insets(10, 10, 10, 10);
+        dialog.getContentPane().add(new JLabel("Takeoff money"), c);
+
+        c.gridx = 0;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(new JLabel("Betrag", SwingConstants.RIGHT), c);
+
+        c.gridx = 1;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(value, c);
+
+        c.gridx = 1;
+        c.gridy = 2;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(cancel, c);
+
+        c.gridx = 2;
+        c.gridy = 2;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(deposit, c);
+    }
+
+    private void createComponents(Account account) {
+        this.dialog = new JDialog();
+
+        this.cancel = new JButton("Abbrechen");
+        this.deposit = new JButton("Auszahlen");
+        this.value = new JFormattedTextField(getNumberFormat(account.getBalance()));
+
+        this.dialog.setContentPane(new JPanel(new GridBagLayout()));
+    }
+
+    public double getAmount() {
+        if (value.getText().isBlank()) {
+            showMessageDialog(null, "invalid amount", "currency must not be blank", ERROR_MESSAGE);
+            return 0;
+        }
+
+        try {
+            return NumberFormat.getNumberInstance().parse(value.getText()).doubleValue();
+        } catch (ParseException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public JButton getCancel() {
+        return cancel;
+    }
+
+    public JButton getDeposit() {
+        return deposit;
+    }
+
+    public void dispose() {
+        this.dialog.dispose();
+    }
+}

src/me/teridax/jcash/gui/transfer/TransferDialog.java

@@ -0,0 +1,17 @@
+package me.teridax.jcash.gui.transfer;
+
+import me.teridax.jcash.banking.Account;
+
+public class TransferDialog {
+
+    public TransferDialog(Account account, Runnable onDeposit) {
+        var view = new TransferView(account);
+        view.getDeposit().addActionListener(e -> {
+            account.takeoff(view.getAmount());
+            onDeposit.run();
+            view.dispose();
+        });
+        view.getCancel().addActionListener(e -> view.dispose());
+        view.showDialog();
+    }
+}

src/me/teridax/jcash/gui/transfer/TransferView.java

@@ -0,0 +1,168 @@
+package me.teridax.jcash.gui.transfer;
+
+import me.teridax.jcash.banking.Account;
+
+import javax.swing.*;
+import javax.swing.text.NumberFormatter;
+import java.awt.*;
+import java.text.NumberFormat;
+import java.text.ParseException;
+import java.util.Locale;
+
+import static javax.swing.JOptionPane.ERROR_MESSAGE;
+import static javax.swing.JOptionPane.showMessageDialog;
+
+public class TransferView {
+
+    private JDialog dialog;
+    private JButton cancel;
+    private JButton deposit;
+    private JFormattedTextField iban;
+    private JFormattedTextField blz;
+    private JFormattedTextField value;
+
+    public TransferView(Account account) {
+        createComponents(account);
+        layoutComponents();
+    }
+
+    public void showDialog() {
+        dialog.setModalityType(Dialog.ModalityType.APPLICATION_MODAL);
+        dialog.setTitle("Deposit money");
+        dialog.pack();
+        dialog.setResizable(false);
+        dialog.setLocationRelativeTo(null);
+        dialog.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
+        dialog.setVisible(true);
+    }
+
+    private NumberFormatter getNumberFormat(double balance) {
+        var format = NumberFormat.getNumberInstance(Locale.GERMANY);
+        format.setParseIntegerOnly(false);
+        format.setMaximumFractionDigits(2);
+
+        var formatter = new NumberFormatter(format);
+        formatter.setValueClass(Double.class);
+        formatter.setAllowsInvalid(true);
+        formatter.setMaximum(balance);
+
+        return formatter;
+    }
+
+    private void layoutComponents() {
+        dialog.getContentPane().setLayout(new GridBagLayout());
+
+        var c = new GridBagConstraints();
+        c.gridx = 0;
+        c.gridy = 0;
+        c.weightx = 1;
+        c.weighty = 1;
+        c.fill = GridBagConstraints.BOTH;
+        c.anchor = GridBagConstraints.CENTER;
+        c.insets = new Insets(10, 10, 10, 10);
+        dialog.getContentPane().add(new JLabel("Takeoff money"), c);
+
+        c.gridx = 0;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(new JLabel("BLZ", SwingConstants.RIGHT), c);
+
+        c.gridx = 1;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(blz, c);
+
+        c.gridx = 2;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(new JLabel("IBAN", SwingConstants.RIGHT), c);
+
+        c.gridx = 3;
+        c.gridy = 1;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(iban, c);
+
+        c.gridx = 0;
+        c.gridy = 2;
+        c.fill = GridBagConstraints.NONE;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 0;
+        dialog.getContentPane().add(new JLabel("Betrag", SwingConstants.RIGHT), c);
+
+        c.gridx = 1;
+        c.gridy = 2;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(value, c);
+
+        c.gridx = 2;
+        c.gridy = 3;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(cancel, c);
+
+        c.gridx = 3;
+        c.gridy = 3;
+        c.fill = GridBagConstraints.HORIZONTAL;
+        c.anchor = GridBagConstraints.LAST_LINE_END;
+        c.insets = new Insets(10, 10, 10, 10);
+        c.weightx = 1;
+        dialog.getContentPane().add(deposit, c);
+
+        dialog.getContentPane().add(value, c);
+    }
+
+    private void createComponents(Account account) {
+        this.dialog = new JDialog();
+
+        this.cancel = new JButton("Abbrechen");
+        this.deposit = new JButton("Auszahlen");
+        this.value = new JFormattedTextField(getNumberFormat(account.getBalance()));
+        this.iban = new JFormattedTextField();
+        this.blz = new JFormattedTextField();
+
+        this.dialog.setContentPane(new JPanel(new GridBagLayout()));
+    }
+
+    public double getAmount() {
+        if (value.getText().isBlank()) {
+            showMessageDialog(null, "invalid amount", "currency must not be blank", ERROR_MESSAGE);
+            return 0;
+        }
+
+        try {
+            return NumberFormat.getNumberInstance().parse(value.getText()).doubleValue();
+        } catch (ParseException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    public JButton getCancel() {
+        return cancel;
+    }
+
+    public JButton getDeposit() {
+        return deposit;
+    }
+
+    public void dispose() {
+        this.dialog.dispose();
+    }
+}