added information about submission grade

README.md

@@ -4,6 +4,8 @@
 
 Draft program for the Java class of semester 2. The goal was to simulate basic cash machine that can read customer data from a `.csv` file and let the user view the data with crude forms of authentication.
 
+> This project was graded with 100,0 out of 100,0 points
+
 ## Overview
 
 The program can read `.csv` file from disk and allows the user login to an account specified.

src/me/teridax/jcash/Logging.java

@@ -7,6 +7,8 @@ import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
 import java.util.logging.*;
 
+import static java.nio.file.Path.of;
+
 /**
  * Utility class for providing a global logger for the entire application instance at runtime
  */
@@ -45,7 +47,7 @@ public final class Logging {
      * @param level the level to set the handler to
      */
     private static void createConsoleLogger(Level level) {
-        var ch = new ConsoleHandler();
+        ConsoleHandler ch = new ConsoleHandler();
         ch.setLevel(level);
         LOGGER.addHandler(ch);
     }
@@ -60,15 +62,15 @@ public final class Logging {
      */
     private static void createFileLogger(Level level) {
         // setup log file name
-        var now = LocalDateTime.now();
-        var dateTime = DateTimeFormatter.ofPattern(DATE_TIME_FORMAT).format(now);
-        var logFileName = LOG_FOLDER_NAME + dateTime + ".log";
+        LocalDateTime now = LocalDateTime.now();
+        String dateTime = DateTimeFormatter.ofPattern(DATE_TIME_FORMAT).format(now);
+        String logFileName = LOG_FOLDER_NAME + dateTime + ".log";
 
         // setup the folder for the logs
         initializeLogFolder();
 
         try {
-            var fh = new FileHandler(logFileName);
+            FileHandler fh = new FileHandler(logFileName);
             fh.setLevel(level);
             LOGGER.addHandler(fh);
         } catch (Exception e) {
@@ -81,7 +83,7 @@ public final class Logging {
      * If the folder does not exist, the function will create a new folder.
      */
     private static void initializeLogFolder() {
-        var folderPath = Path.of(LOG_FOLDER_NAME);
+        Path folderPath = of(LOG_FOLDER_NAME);
 
         if (Files.isDirectory(folderPath))
             return;

src/me/teridax/jcash/Main.java

@@ -1,11 +1,9 @@
 package me.teridax.jcash;
 
-import me.teridax.jcash.banking.management.BankingManagementSystem;
 import me.teridax.jcash.gui.IconProvider;
 import me.teridax.jcash.gui.Loader;
+import me.teridax.jcash.gui.MainFrame;
 import me.teridax.jcash.gui.Utils;
-import me.teridax.jcash.gui.account.AccountController;
-import me.teridax.jcash.gui.login.LoginController;
 import me.teridax.jcash.lang.Locales;
 
 import javax.swing.*;
@@ -16,82 +14,38 @@ import java.util.logging.Level;
 
 import static me.teridax.jcash.Logging.LOGGER;
 import static me.teridax.jcash.Logging.initializeSystemLogger;
-import static me.teridax.jcash.lang.Translator.translate;
 
 public final class Main {
 
-    private static final String LOGIN_SCREEN_STRING_IDENT = "LoginScreen";
-    private static final String PROFILE_SCREEN_STRING_IDENT = "ProfileScreen";
-    private static final String VERSION = "v2.0.0";
-
     /**
      * Main instance of this program. Contains the primary window.
      */
     private static Main instance;
 
     /**
-     * Primary window of this program
+     * Primary class for controlling GUI of this application
      */
-    private final JFrame window;
-    private final CardLayout layout;
-
-    private BankingManagementSystem bms;
-
-    private LoginController loginMask;
-    private AccountController accountController;
+    private final MainFrame window;
 
     private Main() {
-        // create main window and set defaults
-        this.window = new JFrame();
-        this.window.setTitle(translate("Cashmachine") + getInfoString());
-        this.window.setLocationByPlatform(true);
-        this.window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
-        this.window.setIconImage(IconProvider.getWindowIcon());
-
-        this.layout = new CardLayout();
-        this.window.getContentPane().setLayout(this.layout);
-
-        initialize();
-    }
-
-    private String getInfoString() {
-        return " locale: [" + Locales.getDefaultLocale().toString() + "] " + VERSION;
-    }
-
-    private void initialize() {
-        // create the login mask
-
-        this.loginMask = new LoginController();
-
-        // when we have logged in set the account viewer as window content
-        this.loginMask.addAccountSelectionListener(account -> {
-            LOGGER.finer("account selected: " + Objects.toString(account, "null"));
-            accountController.setProfile(account, bms);
-            layout.show(window.getContentPane(), PROFILE_SCREEN_STRING_IDENT);
-        });
-
-        this.window.getContentPane().add(loginMask.getView(), LOGIN_SCREEN_STRING_IDENT);
-
-        // create the account viewer
-
-        this.accountController = new AccountController();
-        this.window.getContentPane().add(accountController.getView(), PROFILE_SCREEN_STRING_IDENT);
+        this.window = new MainFrame();
     }
 
+    /**
+     * Prompts the user a dialog to select a file to load the database from.
+     * If a valid database has been read a login screen will be shown.
+     * If no file was selected or the database was invalid the application will close.
+     */
     public void loadDatabase() {
         try {
-            this.bms = Loader.load();
+            var bms = Loader.load();
+            this.window.setBms(bms);
+
         } catch (Exception e) {
             LOGGER.severe("Failed to load database: " + e.getMessage());
             Utils.error("Failed to load database");
             System.exit(1);
         }
-        this.loginMask.setBankingManagementSystem(bms);
-        showLoginScreen();
-        this.window.pack();
-        this.window.setResizable(false);
-        this.window.setLocationRelativeTo(null);
-        this.window.setVisible(true);
     }
 
     public static void main(String[] args) {
@@ -181,24 +135,16 @@ public final class Main {
         Main.instance = new Main();
     }
 
-    /**
-     * Shows the open dialog for selecting a database file. After selection, it then proceeds to prompt login.
-     * Afterward the selected account can be managed.
-     * This method is non-blocking and all work described is performed asynchronously on the AWT Event dispatcher.
-     */
-    public void showLoginScreen() {
-        this.layout.show(this.window.getContentPane(), LOGIN_SCREEN_STRING_IDENT);
+    public JFrame getWindow() {
+        return this.window.getWindow();
     }
 
     /**
-     * Logs the user out of the database, hiding the main window.
+     * Logs the user out of the currently open account.
+     * This will show the login mask and clear the password field or the previous
+     * login attempt.
      */
     public void logout() {
-        this.loginMask.logout();
-        this.layout.show(this.window.getContentPane(), LOGIN_SCREEN_STRING_IDENT);
-    }
-
-    public JFrame getWindow() {
-        return this.window;
+        this.window.logout();
     }
 }

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

@@ -6,6 +6,8 @@ import me.teridax.jcash.banking.accounts.Owner;
 import me.teridax.jcash.decode.StringDecoder;
 
 import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.*;
@@ -23,6 +25,13 @@ public final class BankingManagementSystem {
      * Separator used to separate columns of CSV files
      */
     private static final String SEPARATOR = ";";
+    /**
+     * Charsets to try when decoding the source file
+     */
+    private static final Charset[] ENCODINGS = {
+            StandardCharsets.UTF_8,
+            Charset.forName("windows-1252")
+    };
 
     /**
      * A set of banks
@@ -76,7 +85,7 @@ public final class BankingManagementSystem {
         LOGGER.fine("parsing banking management system from file: " + Objects.toString(file, "null"));
         try {
             var bms = new BankingManagementSystem();
-            var content = Files.readString(file);
+            var content = getSource(file);
 
             // read line by line
             // and skip the first line
@@ -114,15 +123,33 @@ public final class BankingManagementSystem {
 
             return bms;
 
-        } catch (IOException e) {
-            LOGGER.severe("Could not read file: " + file + " due to: " + e.getMessage());
-            throw new IllegalArgumentException("Could not read file " + file, e);
         } catch (IllegalArgumentException | NullPointerException e) {
             LOGGER.severe("Could not parse file: " + file + " due to: " + e.getMessage());
             throw new IllegalArgumentException("Could not parse file " + file, e);
         }
     }
 
+    /**
+     * Attempts to read the entire file into a string.
+     * This method tires out all encodings in {@link #ENCODINGS}
+     * @param file the file to read
+     * @throws IllegalArgumentException if the file cannot be read
+     * @return the content of the file
+     */
+    private static String getSource(Path file) throws IllegalArgumentException {
+        Exception lastException = null;
+        for (var encoding : ENCODINGS) {
+            try {
+                return Files.readString(file, encoding);
+            } catch (IOException e) {
+                LOGGER.severe("Could not read file: " + file + " due to: " + e.getMessage());
+                lastException = e;
+            }
+        }
+        assert lastException != null;
+        throw new IllegalArgumentException("Invalid encoding, or IO exception: " + lastException.getMessage());
+    }
+
     /**
      * Return a bank with the given blz.
      *

src/me/teridax/jcash/decode/StringDecoder.java

@@ -18,6 +18,10 @@ public class StringDecoder {
         return NumberFormat.getInstance(Locales.getDefaultLocale());
     }
 
+    /**
+     * Returns a NumberFormatter for parsing double values in the appropriate locale.
+     * @return the number formatter
+     */
     public static NumberFormatter getNumberFormatter(double maxValue) {
         var formatter = new NumberFormatter();
         formatter.setValueClass(Double.class);
@@ -29,7 +33,11 @@ public class StringDecoder {
         return formatter;
     }
 
-    public static Object getIntegerNumberFormatter() {
+    /**
+     * Returns a NumberFormatter for parsing integer values in the appropriate locale.
+     * @return the number formatter
+     */
+    public static NumberFormatter getIntegerNumberFormatter() {
         var formatter = new NumberFormatter();
         formatter.setValueClass(Integer.class);
         formatter.setMinimum(0d);

src/me/teridax/jcash/gui/IconProvider.java

@@ -7,14 +7,28 @@ import java.util.Objects;
 
 import static me.teridax.jcash.Logging.LOGGER;
 
+/**
+ * Static class for providing the capabilities to load images from file.
+ */
 public class IconProvider {
 
     private static final Image DEFAULT_IMAGE = new BufferedImage(256, 256, BufferedImage.TYPE_INT_RGB);
 
+    /**
+     * Fetches the windows icon.
+     * @return the windows icon
+     */
     public static Image getWindowIcon() {
         return loadIcon("res/register.png");
     }
 
+    /**
+     * Loads the specified image from disk.
+     * If the file cannot be made into an image because its corrupted or the file cannot be read,
+     * the default image is returned {@link #DEFAULT_IMAGE}
+     * @param path the path to the image
+     * @return the specified image or {@link #DEFAULT_IMAGE}
+     */
     private static Image loadIcon(String path) {
         try {
             var is = Objects.requireNonNull(IconProvider.class.getResourceAsStream(path));
@@ -26,6 +40,10 @@ public class IconProvider {
         return DEFAULT_IMAGE;
     }
 
+    /**
+     * Fetches the background image used for the login screen
+     * @return login screen background image
+     */
     public static Image getBackground() {
         return loadIcon("res/background.png");
     }

src/me/teridax/jcash/gui/InvalidInputException.java

@@ -1,7 +1,10 @@
 package me.teridax.jcash.gui;
 
-import java.text.ParseException;
 
+/**
+ * Exception thrown when some user input is invalid
+ */
+@SuppressWarnings("unused")
 public class InvalidInputException extends IllegalStateException {
 
     public InvalidInputException(String message, Exception cause) {

src/me/teridax/jcash/gui/MainFrame.java

@@ -0,0 +1,128 @@
+package me.teridax.jcash.gui;
+
+import me.teridax.jcash.banking.management.BankingManagementSystem;
+import me.teridax.jcash.gui.account.AccountController;
+import me.teridax.jcash.gui.login.LoginController;
+import me.teridax.jcash.lang.Locales;
+
+import javax.swing.*;
+import java.awt.*;
+import java.util.Objects;
+
+import static me.teridax.jcash.Logging.LOGGER;
+import static me.teridax.jcash.lang.Translator.translate;
+
+public class MainFrame {
+
+    /**
+     * Constant used to identify the login screen on the cardlayout
+     */
+    private static final String LOGIN_SCREEN_STRING_IDENT = "LoginScreen";
+    /**
+     * Constant used to identify the profile screen on the cardlayout
+     */
+    private static final String PROFILE_SCREEN_STRING_IDENT = "ProfileScreen";
+    /**
+     * Version of this application
+     */
+    private static final String VERSION = "v2.1.0";
+
+    /**
+     * Primary window of this program
+     */
+    private final JFrame window;
+    /**
+     * Primary layout of this application
+     */
+    private final CardLayout layout;
+
+    /**
+     * Database containing every bank, account and owner available
+     */
+    private BankingManagementSystem bms;
+
+    private LoginController loginMask;
+    private AccountController accountController;
+
+    public MainFrame() {
+        // create main window and set defaults
+        this.window = new JFrame();
+        this.window.setTitle(translate("Cashmachine") + getInfoString());
+        this.window.setLocationByPlatform(true);
+        this.window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+        this.window.setIconImage(IconProvider.getWindowIcon());
+
+        this.layout = new CardLayout();
+        this.window.getContentPane().setLayout(this.layout);
+
+        initialize();
+    }
+
+
+    /**
+     * Creates and returns a general information string about this application
+     * @return the locale and the current version as string
+     */
+    private String getInfoString() {
+        return " locale: [" + Locales.getDefaultLocale().toString() + "] " + VERSION;
+    }
+
+    /**
+     * Initializes the GUI components of login screen and profile view
+     */
+    private void initialize() {
+        // create the login mask
+
+        this.loginMask = new LoginController();
+
+        // when we have logged in set the account viewer as window content
+        this.loginMask.addAccountSelectionListener(account -> {
+            LOGGER.finer("account selected: " + Objects.toString(account, "null"));
+            accountController.setProfile(account, bms);
+            layout.show(window.getContentPane(), PROFILE_SCREEN_STRING_IDENT);
+        });
+
+        this.window.getContentPane().add(loginMask.getView(), LOGIN_SCREEN_STRING_IDENT);
+
+        // create the account viewer
+
+        this.accountController = new AccountController();
+        this.window.getContentPane().add(accountController.getView(), PROFILE_SCREEN_STRING_IDENT);
+    }
+
+    /**
+     * Sets the BMS of this application to use for the GUI.
+     * This method will show the login screen to the user
+     * @param bms the BMS to use for the GUI
+     */
+    public void setBms(BankingManagementSystem bms) {
+        this.bms = bms;
+        this.loginMask.setBankingManagementSystem(bms);
+        this.showLoginScreen();
+        this.window.pack();
+        this.window.setResizable(false);
+        this.window.setLocationRelativeTo(null);
+        this.window.setVisible(true);
+    }
+
+    /**
+     * Shows the open dialog for selecting a database file. After selection, it then proceeds to prompt login.
+     * Afterward the selected account can be managed.
+     * This method is non-blocking and all work described is performed asynchronously on the AWT Event dispatcher.
+     */
+    private void showLoginScreen() {
+        this.layout.show(this.window.getContentPane(), LOGIN_SCREEN_STRING_IDENT);
+    }
+
+    /**
+     * Logs the user out of the database, hiding the main window.
+     */
+    public void logout() {
+        this.loginMask.logout();
+        this.layout.show(this.window.getContentPane(), LOGIN_SCREEN_STRING_IDENT);
+    }
+
+    public JFrame getWindow() {
+        return this.window;
+    }
+}

src/me/teridax/jcash/gui/Utils.java

@@ -10,6 +10,14 @@ import java.text.NumberFormat;
 
 public class Utils {
 
+    /**
+     * Formats the string so that it will be displayed as a Heading 1 element by JLabels.
+     * This embeds the given string into two html tags.
+     * Note that eny html entities in the string will be formatted as valid HTML entities.
+     * Meaning they won't show up in as plain text.
+     * @param title the title to format.
+     * @return the given string embedded into <pre>&lt;html>&lt;h1>$string&lt;/h1>&lt;/html></pre>
+     */
     public static String addHeading(String title) {
         return String.format("<html><h1>%s</h1></html>", title);
     }

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

@@ -25,6 +25,11 @@ public class AccountController {
         this.data = new AccountData();
     }
 
+    /**
+     * Sets the profile and BMS used to manage banking.
+     * @param profile the profile used to manage the account
+     * @param bms the BMS used access other banking accounts
+     */
     public void setProfile(Profile profile, BankingManagementSystem bms) {
         this.profile = profile;
         this.view.setProfile(profile);
@@ -32,6 +37,9 @@ public class AccountController {
         this.createListeners();
     }
 
+    /**
+     * Create listeners for GUI components
+     */
     private void createListeners() {
         this.view.getAccountSelection().addActionListener(e -> changeAccount());
         this.view.getLogout().addActionListener(e -> logout());
@@ -40,16 +48,25 @@ public class AccountController {
         this.view.getTransfer().addActionListener(e -> transferMoney());
     }
 
+    /**
+     * Open dialog to deposit money
+     */
     private void depositMoney() {
         new DepositController(profile.getPrimaryAccount());
         this.view.updateAccountVariables(profile);
     }
 
+    /**
+     * Open dialog to transfer money
+     */
     private void transferMoney() {
         new TransferController(profile.getPrimaryAccount(), data.getBms());
         this.view.updateAccountVariables(profile);
     }
 
+    /**
+     * Open dialog to take off money
+     */
     private void takeoffMoney() {
         new TakeoffController(profile.getPrimaryAccount());
         this.view.updateAccountVariables(profile);
@@ -58,9 +75,11 @@ public class AccountController {
     private void logout() {
         Logging.LOGGER.fine("Logging out of account");
         Main.getInstance().logout();
-        Main.getInstance().showLoginScreen();
     }
 
+    /**
+     * Change the selected account.
+     */
     private void changeAccount() {
         var description = ((String) this.view.getAccountSelection().getSelectedItem());
         Logging.LOGGER.fine("Changing primary account selected: " + description);

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

@@ -2,6 +2,9 @@ package me.teridax.jcash.gui.account;
 
 import me.teridax.jcash.banking.management.BankingManagementSystem;
 
+/**
+ * Data storage class for account management
+ */
 public class AccountData {
 
     private BankingManagementSystem bms;

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

@@ -40,6 +40,10 @@ public class AccountView extends JPanel {
         setBorder(BorderFactory.createEmptyBorder(8, 8, 8, 8));
     }
 
+    /**
+     * The profile to manage via the GUI.
+     * @param profile the profile to manage
+     */
     public void setProfile(Profile profile) {
         this.updateAccountVariables(profile);
 
@@ -137,8 +141,15 @@ public class AccountView extends JPanel {
         return takeoff;
     }
 
+    /**
+     * Writes the accessible class fields of the primary account
+     * into the text fields. Also updates the combo box for
+     * all associated accounts.
+     * @param profile the profile to update from
+     */
     public void updateAccountVariables(Profile profile) {
         Logging.LOGGER.finer("Updating account view");
+        // temporarily extract data
         var bank = profile.getBank();
         var account = profile.getPrimaryAccount();
         var owner = profile.getOwner();
@@ -152,6 +163,8 @@ public class AccountView extends JPanel {
 
         this.balance.setText(StringDecoder.getNumberFormat().format(account.getBalance()) + " €");
 
+        // update account type specific fields
+
         this.type.setText(translate(account.getClass().getSimpleName()));
         if (account instanceof CurrentAccount) {
             this.typeSpecialLabel.setText(translate("Overdraft"));

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

@@ -9,21 +9,30 @@ import javax.swing.event.DocumentEvent;
 import javax.swing.event.DocumentListener;
 import java.text.ParseException;
 
+/**
+ * Class for controlling the deposit operation via a dialog.
+ */
 public class DepositController {
 
     private final DepositView view;
+    /**
+     * Account to deposit money to.
+     */
     private final Account account;
-    private final DepositData data;
 
     public DepositController(Account account) {
         this.account = account;
 
-        this.data = new DepositData(account.getBalance());
-        this.view = new DepositView(this.data.getMaxValue());
+        this.view = new DepositView(account.getBalance());
 
         this.view.getDeposit().addActionListener(e -> depositMoney());
         this.view.getCancel().addActionListener(e -> view.dispose());
         this.view.getValue().getDocument().addDocumentListener(new DocumentListener() {
+
+            /**
+             * Validate the amount to deposit and update display
+             * variables.
+             */
             private void validateInputState() {
                 var balance = account.getBalance();
                 try {
@@ -55,6 +64,10 @@ public class DepositController {
         this.view.showDialog();
     }
 
+    /**
+     * Deposit the last valid value to the account.
+     * This method may display error dialogs when no money can be deposited.
+     */
     private void depositMoney() {
         try {
             var amount = view.getAmount();

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

@@ -1,14 +0,0 @@
-package me.teridax.jcash.gui.deposit;
-
-public class DepositData {
-
-    private double maxValue;
-
-    public DepositData(double maxValue) {
-        this.maxValue = maxValue;
-    }
-
-    public double getMaxValue() {
-        return maxValue;
-    }
-}

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

@@ -11,12 +11,28 @@ import java.text.ParseException;
 
 import static me.teridax.jcash.lang.Translator.translate;
 
+/**
+ * View class for displaying a dialog prompting the user to
+ * enter a valid amount to deposit at their account
+ */
 public class DepositView {
 
+    /**
+     * Window to use
+     */
     private JDialog dialog;
     private JButton cancel;
+    /**
+     * Button for applying the deposit operation
+     */
     private JButton deposit;
+    /**
+     * Displays the validated value to deposit
+     */
     private JLabel enteredValue;
+    /**
+     * Displays the account balance after the deposit operation
+     */
     private JLabel balanceAfterDeposit;
     private JFormattedTextField value;
 
@@ -119,6 +135,12 @@ public class DepositView {
         this.dialog.setContentPane(new JPanel(new GridBagLayout()));
     }
 
+    /**
+     * Returns the amount of money that should be deposited
+     * This value derives from the input of the user.
+     * @return the value to deposit
+     * @throws InvalidInputException if the user entered something invalid
+     */
     public double getAmount() throws InvalidInputException {
         if (value.getText().isBlank())
             throw new InvalidInputException("currency value is blank or has been invalid whilst entered");
@@ -147,6 +169,11 @@ public class DepositView {
         this.dialog.dispose();
     }
 
+    /**
+     * Sets the supplied amount to the preview GUI fields.
+     * @param amount the value to display for value to deposit
+     * @param after the value to display for balance after deposit
+     */
     public void setCommittedValue(double amount, double after) {
         enteredValue.setText(StringDecoder.getNumberFormat().format(amount));
         balanceAfterDeposit.setText(StringDecoder.getNumberFormat().format(after));

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

@@ -7,10 +7,6 @@ import me.teridax.jcash.gui.Utils;
 import java.awt.event.ActionEvent;
 import java.util.Optional;
 
-import static javax.swing.JOptionPane.ERROR_MESSAGE;
-import static javax.swing.JOptionPane.showMessageDialog;
-import static me.teridax.jcash.lang.Translator.translate;
-
 public class LoginController {
 
     private final LoginView view;

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

@@ -46,10 +46,6 @@ public class LoginData {
         return account;
     }
 
-    public BankingManagementSystem getBms() {
-        return bms;
-    }
-
     public void setBms(BankingManagementSystem bms) {
         this.bms = bms;
     }

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

@@ -1,6 +1,5 @@
 package me.teridax.jcash.gui.login;
 
-import me.teridax.jcash.decode.StringDecoder;
 import me.teridax.jcash.gui.IconProvider;
 
 import javax.swing.*;
@@ -11,6 +10,9 @@ import static me.teridax.jcash.gui.Utils.addGridBagRow;
 import static me.teridax.jcash.gui.Utils.addHeading;
 import static me.teridax.jcash.lang.Translator.translate;
 
+/**
+ * GUI class for login into an account
+ */
 public class LoginView extends JPanel {
 
     /**
@@ -18,6 +20,10 @@ public class LoginView extends JPanel {
      * N = log10(2^32-1) = 9,632959861146281
      */
     private static final int MAX_PIN_DECIMAL_DIGITS = 9;
+    /**
+     * Number of pixels the banner image should be in width
+     */
+    public static final int BANNER_WIDTH = 400;
 
     private JFormattedTextField blz;
     private JFormattedTextField iban;
@@ -37,7 +43,7 @@ public class LoginView extends JPanel {
         var loginPane = new JPanel(new GridBagLayout());
         loginPane.setOpaque(true);
         content.add(loginPane, BorderLayout.CENTER);
-        content.add(Box.createHorizontalStrut(400), BorderLayout.WEST);
+        content.add(Box.createHorizontalStrut(BANNER_WIDTH), BorderLayout.WEST);
 
         this.setLayout(new BorderLayout(32, 32));
         this.add(new JScrollPane(content), BorderLayout.CENTER);
@@ -66,6 +72,8 @@ public class LoginView extends JPanel {
         this.pin = new JPasswordField();
         this.login = new JButton(translate("Login"));
 
+        // customize login button
+        // this may not work with every swing look and feel
         this.login.setFont(new Font("Circus", Font.PLAIN, 28));
         this.login.setBackground(Color.CYAN);
 

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

@@ -10,22 +10,32 @@ import javax.swing.event.DocumentEvent;
 import javax.swing.event.DocumentListener;
 import java.text.ParseException;
 
+/**
+ * Controller class for handling bank account take off.
+ */
 public class TakeoffController {
 
+    /**
+     * Account to take off
+     */
     private final Account account;
+    /**
+     * GUI object
+     */
     private final TakeoffView view;
-    private final TakeoffData data;
 
     public TakeoffController(Account account) {
         this.account = account;
 
+        // add overdraft on top of the maximum amount
+        // a user is allowed to take off
         var overdraft = 0.0;
         if (account instanceof CurrentAccount) {
             overdraft += ((CurrentAccount) account).getOverdraft();
         }
 
-        this.data = new TakeoffData(account.getBalance());
-        this.view = new TakeoffView(this.data.getMaxValue() + overdraft);
+        TakeoffData data = new TakeoffData(account.getBalance());
+        this.view = new TakeoffView(data.getMaxValue() + overdraft);
 
         this.view.getTakeoff().addActionListener(e -> takeOff());
         this.view.getCancel().addActionListener(e -> view.dispose());
@@ -61,6 +71,9 @@ public class TakeoffController {
         this.view.showDialog();
     }
 
+    /**
+     * Attempts to take off some money from an account.
+     */
     private void takeOff() {
         try {
             account.takeoff(view.getAmount());

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

@@ -1,7 +1,13 @@
 package me.teridax.jcash.gui.takeoff;
 
+/**
+ * Data class for taking off value from a certain account
+ */
 public class TakeoffData {
 
+    /**
+     * Maximum value a user is allowed to take off
+     */
     private final double maxValue;
 
     public TakeoffData(double maxValue) {

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

@@ -11,6 +11,9 @@ import java.text.ParseException;
 
 import static me.teridax.jcash.lang.Translator.translate;
 
+/**
+ * Dialog for taking off money of an account.
+ */
 public class TakeoffView {
 
     private JDialog dialog;
@@ -25,6 +28,9 @@ public class TakeoffView {
         layoutComponents();
     }
 
+    /**
+     * Makes this dialog visible.
+     */
     public void showDialog() {
         dialog.setIconImage(IconProvider.getWindowIcon());
         dialog.setModalityType(Dialog.ModalityType.APPLICATION_MODAL);
@@ -104,6 +110,10 @@ public class TakeoffView {
         dialog.getContentPane().add(buttonPanel, c);
     }
 
+    /**
+     * The createComponents function creates the components of the dialog.
+     * @param maxValue Set the maximum value of the jformattedtextfield
+     */
     private void createComponents(double maxValue) {
         this.dialog = new JDialog();
 
@@ -116,6 +126,10 @@ public class TakeoffView {
         this.dialog.setContentPane(new JPanel(new GridBagLayout()));
     }
 
+    /**
+     * The getAmount function is used to get the amount of currency that has been entered into the text field.
+     * @return A double value, which is the parsed amount from the text field
+     */
     public double getAmount() throws InvalidInputException {
         if (value.getText().isBlank())
             throw new InvalidInputException("currency value is blank or has been invalid whilst entered");
@@ -128,6 +142,13 @@ public class TakeoffView {
         }
     }
 
+
+    /**
+     * The setCommittedValue function sets the text of the enteredValue and balanceAfterDeposit TextFields to
+     * a String representation of amount and after, respectively.
+     * @param amount Set the text of enteredvalue
+     * @param after Set the balance after deposit
+     */
     public void setCommittedValue(double amount, double after) {
         enteredValue.setText(StringDecoder.getNumberFormat().format(amount));
         balanceAfterDeposit.setText(StringDecoder.getNumberFormat().format(after));

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

@@ -33,20 +33,9 @@ public class TransferController {
         this.transferData = new TransferData(bms);
         this.view.getTransfer().addActionListener(e -> transfer());
         this.view.getCancel().addActionListener(e -> view.dispose());
-        this.view.getValue().getDocument().addDocumentListener(new DocumentListener() {
-            private void validateInputState() {
-                var balance = account.getBalance();
-                try {
-                    view.getValue().commitEdit();
-                    var amount = view.getAmount();
-                    view.setCommittedValue(amount, balance - amount);
-                    view.getTransfer().setEnabled(true);
-                } catch (InvalidInputException | ParseException ex) {
-                    view.setCommittedValue(0, balance);
-                    view.getTransfer().setEnabled(false);
-                }
-            }
 
+        // validates the users input
+        var validator = new DocumentListener() {
             @Override
             public void insertUpdate(DocumentEvent documentEvent) {
                 validateInputState();
@@ -61,10 +50,53 @@ public class TransferController {
             public void changedUpdate(DocumentEvent documentEvent) {
                 validateInputState();
             }
-        });
+        };
+
+        this.view.getValue().getDocument().addDocumentListener(validator);
+        this.view.getIbanTextField().getDocument().addDocumentListener(validator);
+        this.view.getBlzTextField().getDocument().addDocumentListener(validator);
+
         this.view.showDialog();
     }
 
+    /**
+     * Returns true if the target bank account is valid.
+     * @return  true if the target bank account is valid false otherwise
+     */
+    private boolean validateTargetAccount() {
+        if (transferData.validateBLZ(this.view.getBlz())) {
+            return transferData.validateIBAN(this.view.getBlz(), view.getIban());
+        }
+        return false;
+    }
+
+    /**
+     * Returns true if the entered value to transfer is valid.
+     * This method will also commit the valid value back to the text field.
+     * @return true if the value to transfer is valid, false otherwise
+     */
+    private boolean validateTransferValue() {
+        var balance = account.getBalance();
+        try {
+            view.getValue().commitEdit();
+            var amount = view.getAmount();
+            view.setCommittedValue(amount, balance - amount);
+            return true;
+        } catch (InvalidInputException | ParseException ex) {
+            view.setCommittedValue(0, balance);
+            return false;
+        }
+    }
+
+    private void validateInputState() {
+        var valid = validateTargetAccount() && validateTransferValue();
+        view.getTransfer().setEnabled(valid);
+    }
+
+    /**
+     * Attempts to transfer the balance from one account to another
+     * This method will close the dialog.
+     */
     private void transfer() {
         try {
             var amount = view.getAmount();

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

@@ -46,4 +46,32 @@ public class TransferData {
 
         account.get().getPrimaryAccount().deposit(amount);
     }
+
+    /**
+     * Validates the given BLZ. If no bank with the given BLZ can be found
+     * this method returns false. Otherwise, true is returned.
+     * @param blz the BLZ to validate
+     * @return true if the BLZ is valid and false otherwise
+     */
+    public boolean validateBLZ(String blz) {
+        return bms.getBank(blz).isPresent();
+    }
+
+    /**
+     * Validates the given IBAN for the given BLZ. This method assumes the BLZ to be valid.
+     * If this is not the case, this function will throw an exception.
+     * Returns true if an account with the given IBAN was found for bank of the given BLZ.
+     * @param blz bank to search in
+     * @param ibanString account to search for
+     * @return true if the account was found false otherwise
+     */
+    public boolean validateIBAN(String blz, String ibanString) {
+        var bank = bms.getBank(blz);
+        try {
+            var iban = StringDecoder.decodeUniqueIdentificationNumber(ibanString);
+            return bank.map(value -> value.getAccount(iban).isPresent()).orElse(false);
+        } catch (Exception e) {
+            return false;
+        }
+    }
 }

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

@@ -11,6 +11,24 @@ import java.text.ParseException;
 
 import static me.teridax.jcash.lang.Translator.translate;
 
+/**
+ * JDialog for displaying the GUI for a transfer dialog
+ * with the following crude layout:
+ * <pre>
+ ┌───────────────────────────────────────────────┐
+ │       ┌─────────────┐      ┌────────────────┐ │
+ │   BLZ │             │ IBAN │                │ │
+ │       └─────────────┘      └────────────────┘ │
+ │                                               │
+ │       ┌─────────────┐                         │
+ │ VALUE │             │                         │
+ │       └─────────────┘                         │
+ │                          ┌───────┐ ┌────────┐ │
+ │                          │Cancel │ │Transfer│ │
+ │                          └───────┘ └────────┘ │
+ └───────────────────────────────────────────────┘
+ * </pre>
+ */
 public class TransferView {
 
     private JDialog dialog;
@@ -19,7 +37,6 @@ public class TransferView {
     private JFormattedTextField iban;
     private JFormattedTextField blz;
     private JFormattedTextField value;
-
     private JLabel balanceAfterTransfer;
     private JLabel enteredValue;
 
@@ -28,6 +45,9 @@ public class TransferView {
         layoutComponents();
     }
 
+    /**
+     * Makes this dialog visible to the user
+     */
     public void showDialog() {
         dialog.setIconImage(IconProvider.getWindowIcon());
         dialog.setModalityType(Dialog.ModalityType.APPLICATION_MODAL);
@@ -40,6 +60,9 @@ public class TransferView {
         dialog.setVisible(true);
     }
 
+    /**
+     * Layout all components of this dialog.
+     */
     private void layoutComponents() {
         var c = new GridBagConstraints();
 
@@ -142,6 +165,11 @@ public class TransferView {
         this.dialog.setContentPane(new JPanel(new GridBagLayout()));
     }
 
+    /**
+     * Returns the entered amount parsed into a double value.
+     * @return the amount parsed into a double
+     * @throws InvalidInputException if the text in {@link #value} is not a valid double value.
+     */
     public double getAmount() throws InvalidInputException {
         if (value.getText().isBlank())
             throw new InvalidInputException("currency value is blank or has been invalid whilst entered");
@@ -154,6 +182,11 @@ public class TransferView {
         }
     }
 
+    /**
+     * Sets the values to display in the dialog labels as overview information.
+     * @param amount the amount to transfer
+     * @param after balance after the transfer
+     */
     public void setCommittedValue(double amount, double after) {
         enteredValue.setText(StringDecoder.getNumberFormat().format(amount));
         balanceAfterTransfer.setText(StringDecoder.getNumberFormat().format(after));
@@ -179,6 +212,14 @@ public class TransferView {
         return blz.getText();
     }
 
+    public JFormattedTextField getIbanTextField() {
+        return iban;
+    }
+
+    public JFormattedTextField getBlzTextField() {
+        return blz;
+    }
+
     public void dispose() {
         this.dialog.dispose();
     }

src/me/teridax/jcash/lang/Locales.java

@@ -10,6 +10,9 @@ import java.util.Locale;
 @SuppressWarnings("unused")
 public class Locales {
 
+    /**
+     * Default locale initialized to the fallback locale used by this application.
+     */
     private static Locale defaultLocale = new Locale("en", "EN");
 
     /**

src/me/teridax/jcash/lang/Translator.java

@@ -6,6 +6,11 @@ import java.nio.charset.StandardCharsets;
 import java.util.*;
 import java.util.stream.Collectors;
 
+/**
+ * Static translator class.
+ * This is a very simple translator able to translate base tokens from english into a variety of
+ * configured languages.
+ */
 public final class Translator {
 
     /**