Merge pull request #109 from informatik-ag-ngl/f/invalid_login

Reacting to HandshakeRejectionEvents

pom.xml

@@ -28,7 +28,7 @@
 		<dependency>
 			<groupId>com.github.informatik-ag-ngl</groupId>
 			<artifactId>envoy-common</artifactId>
-			<version>develop-SNAPSHOT</version>
+			<version>v0.2-alpha</version>
 		</dependency>
 	</dependencies>
 

src/main/java/envoy/client/data/Settings.java

@@ -1,4 +1,4 @@
-package envoy.client;
+package envoy.client.data;
 
 import java.io.File;
 import java.io.IOException;
@@ -6,7 +6,6 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.prefs.Preferences;
 
-import envoy.client.data.Config;
 import envoy.client.ui.Color;
 import envoy.client.ui.Theme;
 import envoy.util.SerializationUtils;

src/main/java/envoy/client/data/SettingsItem.java

@@ -1,4 +1,4 @@
-package envoy.client;
+package envoy.client.data;
 
 import java.io.Serializable;
 import java.util.HashMap;

src/main/java/envoy/client/event/HandshakeSuccessfulEvent.java

@@ -0,0 +1,18 @@
+package envoy.client.event;
+
+import envoy.event.Event;
+
+/**
+ * This {@link Event} indicates that a handshake was completed successfully.
+ *
+ * Project: <strong>envoy-client</strong><br>
+ * File: <strong>HandshakeSuccessfulEvent.java</strong><br>
+ * Created: <strong>8 Feb 2020</strong><br>
+ *
+ * @author Leon Hofmeister
+ * @since Envoy v0.3-alpha
+ */
+public class HandshakeSuccessfulEvent extends Event.Valueless {
+
+	private static final long serialVersionUID = -157972384126278855L;
+}

src/main/java/envoy/client/net/Client.java

@@ -42,6 +42,7 @@ public class Client implements Closeable {
 	// Asynchronously initialized during handshake
 	private volatile User		sender;
 	private volatile Contacts	contacts;
+	private volatile boolean	rejected;
 
 	// Configuration and logging
 	private static final Config	config	= Config.getInstance();
@@ -54,16 +55,19 @@ public class Client implements Closeable {
 	 * an exception is thrown.
 	 *
 	 * @param credentials          the login credentials of the user
-	 * @param localDb              the local database used to persist the current
-	 *                             {@link IdGenerator}
 	 * @param receivedMessageCache a message cache containing all unread messages
 	 *                             from the server that can be relayed after
 	 *                             initialization
-	 * @throws Exception if the online mode could not be entered or the request
+	 * @throws TimeLimitExceededException if the server could not be reached
-	 *                   failed for some other reason
+	 * @throws IOException                if the login credentials could not be
-	 * @since Envoy v0.2-alpha
+	 *                                    written
+	 * @throws InterruptedException       if the current thread is interrupted while
+	 *                                    waiting for the handshake response
 	 */
-	public void onlineInit(LoginCredentials credentials, LocalDb localDb, Cache<Message> receivedMessageCache) throws Exception {
+	public void performHandshake(LoginCredentials credentials, Cache<Message> receivedMessageCache)
+			throws TimeLimitExceededException, IOException, InterruptedException {
+		if (online) throw new IllegalStateException("Handshake has already been performed successfully");
+
 		// Establish TCP connection
 		logger.info(String.format("Attempting connection to server %s:%d...", config.getServer(), config.getPort()));
 		socket = new Socket(config.getServer(), config.getPort());
@@ -76,6 +80,9 @@ public class Client implements Closeable {
 		receiver.registerProcessor(User.class, sender -> { logger.info("Acquired user object " + sender); this.sender = sender; });
 		receiver.registerProcessor(Contacts.class, contacts -> { logger.info("Acquired contacts object " + contacts); this.contacts = contacts; });
 		receiver.registerProcessor(Message.class, receivedMessageCache);
+		receiver.registerProcessor(HandshakeRejectionEvent.class, evt -> { rejected = true; EventBus.getInstance().dispatch(evt); });
+
+		rejected = false;
 
 		// Start receiver
 		new Thread(receiver).start();
@@ -87,6 +94,15 @@ public class Client implements Closeable {
 		// Wait for a maximum of five seconds to acquire the sender object
 		long start = System.currentTimeMillis();
 		while (sender == null || contacts == null) {
+
+			// Quit immediately after handshake rejection
+			// This method can then be called again
+			if (rejected) {
+				socket.close();
+				receiver.removeAllProcessors();
+				return;
+			}
+
 			if (System.currentTimeMillis() - start > 5000) throw new TimeLimitExceededException("Did not log in after 5 seconds");
 			Thread.sleep(500);
 		}
@@ -96,8 +112,23 @@ public class Client implements Closeable {
 
 		// Remove user creation processor
 		receiver.removeAllProcessors();
+	}
 
-		// Register processors for message and status handling
+	/**
+	 * Initializes the {@link Receiver} used to process data sent from the server to
+	 * this client.
+	 *
+	 * @param localDb              the local database used to persist the current
+	 *                             {@link IdGenerator}
+	 * @param receivedMessageCache a message cache containing all unread messages
+	 *                             from the server that can be relayed after
+	 *                             initialization
+	 * @throws IOException if no {@link IdGenerator} is present and none could be
+	 *                     requested from the server
+	 * @since Envoy v0.2-alpha
+	 */
+	public void initReceiver(LocalDb localDb, Cache<Message> receivedMessageCache) throws IOException {
+		checkOnline();
 
 		// Process incoming messages
 		final ReceivedMessageProcessor receivedMessageProcessor = new ReceivedMessageProcessor();

src/main/java/envoy/client/net/Receiver.java

@@ -51,7 +51,7 @@ public class Receiver implements Runnable {
 
 				try (ObjectInputStream oin = new ObjectInputStream(new ByteArrayInputStream(objBytes))) {
 					Object obj = oin.readObject();
-					logger.finest("Received object " + obj);
+					logger.info("Received object " + obj);
 
 					// Get appropriate processor
 					@SuppressWarnings("rawtypes")

src/main/java/envoy/client/ui/ChatWindow.java

@@ -12,9 +12,9 @@ import javax.swing.border.EmptyBorder;
 import javax.swing.event.DocumentEvent;
 import javax.swing.event.DocumentListener;
 
-import envoy.client.Settings;
 import envoy.client.data.Chat;
 import envoy.client.data.LocalDb;
+import envoy.client.data.Settings;
 import envoy.client.event.MessageCreationEvent;
 import envoy.client.event.ThemeChangeEvent;
 import envoy.client.net.Client;

src/main/java/envoy/client/ui/ContactsSearchRenderer.java

@@ -6,7 +6,7 @@ import java.awt.Font;
 
 import javax.swing.*;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 import envoy.client.event.SendEvent;
 import envoy.client.ui.list.ComponentList;
 import envoy.client.ui.list.ComponentListCellRenderer;

src/main/java/envoy/client/ui/LoginDialog.java

@@ -2,40 +2,52 @@ package envoy.client.ui;
 
 import java.awt.*;
 import java.awt.event.ItemEvent;
-import java.awt.event.ItemListener;
+import java.io.IOException;
 import java.security.NoSuchAlgorithmException;
 import java.util.Arrays;
+import java.util.logging.Logger;
 
+import javax.naming.TimeLimitExceededException;
 import javax.swing.*;
 import javax.swing.border.EmptyBorder;
 
-import envoy.client.Settings;
+import envoy.client.data.*;
+import envoy.client.event.HandshakeSuccessfulEvent;
+import envoy.client.net.Client;
+import envoy.client.util.EnvoyLog;
 import envoy.data.LoginCredentials;
+import envoy.data.Message;
+import envoy.data.User;
+import envoy.event.EventBus;
+import envoy.event.HandshakeRejectionEvent;
+import envoy.exception.EnvoyException;
 
 /**
  * Project: <strong>envoy-client</strong><br>
  * File: <strong>LoginDialog.java</strong><br>
  * Created: <strong>01.01.2020</strong><br>
- * 
+ *
  * @author Kai S. K. Engelbart
  * @author Maximilian K&auml;fer
  * @since Envoy v0.3-alpha
  */
 public class LoginDialog extends JDialog {
 
-	private final JPanel	contentPanel;
+	private JPanel			contentPanel;
-	private JTextField			textField;
+	private JTextField		textField;
-	private JPasswordField		passwordField;
+	private JPasswordField	passwordField;
-	private JPasswordField		repeatPasswordField;
+	private JPasswordField	repeatPasswordField;
 
 	private JLabel	lblUserName;
 	private JLabel	lblPassword;
 	private JLabel	lblRepeatPassword;
+	private JLabel	errorMessage;
 
 	private GridBagConstraints	gbc_lblRepeatPassword;
 	private GridBagConstraints	gbc_repeatPasswordField;
+	private GridBagConstraints	gbc_errorMessage;
 
-	private JPanel buttonPane;
+	private JPanel			buttonPane;
 	private JTextPane		registerText;
 	private JCheckBox		registerCheckBox;
 	private PrimaryButton	okButton;
@@ -43,15 +55,101 @@ public class LoginDialog extends JDialog {
 
 	private LoginCredentials credentials;
 
-	private static final long serialVersionUID = 352021600833907468L;
+	private final Client			client;
+	private final LocalDb			localDb;
+	private final Cache<Message>	receivedMessageCache;
+
+	private static final Config	config				= Config.getInstance();
+	private static final Logger	logger				= EnvoyLog.getLogger(LoginDialog.class.getSimpleName());
+	private static final long	serialVersionUID	= 352021600833907468L;
+
 	/**
 	 * Displays a dialog enabling the user to enter their user name and password.
-	 * 
+	 *
+	 * @param client               the client used to perform the handshake
+	 * @param localDb              the local database in which data is persisted
+	 * @param receivedMessageCache the cache that stored messages received during
+	 *                             the handshake
 	 * @since Envoy v0.3-alpha
 	 */
-	public LoginDialog() {
+	public LoginDialog(Client client, LocalDb localDb, Cache<Message> receivedMessageCache) {
+		this.client					= client;
+		this.localDb				= localDb;
+		this.receivedMessageCache	= receivedMessageCache;
+
+		// Prepare handshake
+		localDb.loadIdGenerator();
+
+		initUi();
+
+		okButton.addActionListener((evt) -> {
+			try {
+				if (registerCheckBox.isSelected()) {
+					// Check password equality
+					if (Arrays.equals(passwordField.getPassword(), repeatPasswordField.getPassword()))
+						credentials = new LoginCredentials(textField.getText(), passwordField.getPassword(), true);
+					else {
+						JOptionPane.showMessageDialog(this, "The repeated password is not the origional password!");
+						clearPasswordFields();
+					}
+				} else credentials = new LoginCredentials(textField.getText(), passwordField.getPassword(), false);
+				performHandshake();
+			} catch (NoSuchAlgorithmException e) {
+				e.printStackTrace();
+			}
+		});
+
+		// Listen to handshake rejections
+		EventBus.getInstance()
+			.register(HandshakeRejectionEvent.class,
+					evt -> { clearPasswordFields(); errorMessage.setVisible(true); errorMessage.setText(evt.get()); });
+
+		// Exit the application when the dialog is cancelled
+		cancelButton.addActionListener(evt -> { logger.info("The login process has been cancelled. Exiting..."); System.exit(0); });
+
+		// Log in directly if configured
+		if (config.hasLoginCredentials()) {
+			credentials = config.getLoginCredentials();
+			performHandshake();
+			return;
+		}
+
+		setVisible(true);
+	}
+
+	private void performHandshake() {
+		try {
+			client.performHandshake(credentials, receivedMessageCache);
+			if (client.isOnline()) {
+				client.initReceiver(localDb, receivedMessageCache);
+				dispose();
+			}
+		} catch (IOException | InterruptedException | TimeLimitExceededException e) {
+			logger.warning("Could not connect to server. Trying offline mode...");
+			e.printStackTrace();
+			try {
+				// Try entering offline mode
+				localDb.loadUsers();
+				User clientUser = localDb.getUsers().get(credentials.getIdentifier());
+				if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
+				client.setSender(clientUser);
+				JOptionPane.showMessageDialog(null,
+						"A connection to the server could not be established. Starting in offline mode.\n" + e,
+						"Connection error",
+						JOptionPane.WARNING_MESSAGE);
+				dispose();
+			} catch (Exception e1) {
+				JOptionPane.showMessageDialog(null, e1, "Client error", JOptionPane.ERROR_MESSAGE);
+				System.exit(1);
+				return;
+			}
+		}
+	}
+
+	private void initUi() {
 		setSize(338, 123);
 		setLocationRelativeTo(null);
+		setResizable(false);
 		getContentPane().setLayout(new BorderLayout());
 		contentPanel = new JPanel();
 		contentPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
@@ -62,137 +160,121 @@ public class LoginDialog extends JDialog {
 		gbl_contentPanel.columnWeights	= new double[] { 0.0, 1.0, Double.MIN_VALUE };
 		gbl_contentPanel.rowWeights		= new double[] { 0.0, 0.0, Double.MIN_VALUE };
 		contentPanel.setLayout(gbl_contentPanel);
-		{
-			lblUserName = new JLabel("Username:");
-			GridBagConstraints	gbc_lblUserName	= new GridBagConstraints();
-			gbc_lblUserName.anchor	= GridBagConstraints.EAST;
-			gbc_lblUserName.insets	= new Insets(0, 0, 5, 5);
-			gbc_lblUserName.gridx	= 0;
-			gbc_lblUserName.gridy	= 0;
-			contentPanel.add(lblUserName, gbc_lblUserName);
-		}
-		{
-			textField = new JTextField();
-			textField.setBorder(null);
-			GridBagConstraints gbc_textField = new GridBagConstraints();
-			gbc_textField.insets	= new Insets(0, 0, 5, 0);
-			gbc_textField.fill		= GridBagConstraints.HORIZONTAL;
-			gbc_textField.gridx		= 1;
-			gbc_textField.gridy		= 0;
-			contentPanel.add(textField, gbc_textField);
-			textField.setColumns(10);
-		}
-		{
-			lblPassword = new JLabel("Password:");
-			GridBagConstraints	gbc_lblPassword	= new GridBagConstraints();
-			gbc_lblPassword.anchor	= GridBagConstraints.EAST;
-			gbc_lblPassword.insets	= new Insets(0, 0, 0, 5);
-			gbc_lblPassword.gridx	= 0;
-			gbc_lblPassword.gridy	= 1;
-			contentPanel.add(lblPassword, gbc_lblPassword);
-		}
-		{
-			passwordField = new JPasswordField();
-			passwordField.setBorder(null);
-			GridBagConstraints gbc_passwordField = new GridBagConstraints();
-			gbc_passwordField.fill	= GridBagConstraints.HORIZONTAL;
-			gbc_passwordField.gridx	= 1;
-			gbc_passwordField.gridy	= 1;
-			contentPanel.add(passwordField, gbc_passwordField);
-		}
-		{
-			lblRepeatPassword				= new JLabel("Repeat Password:");
-			gbc_lblRepeatPassword			= new GridBagConstraints();
-			gbc_lblRepeatPassword.anchor	= GridBagConstraints.EAST;
-			gbc_lblRepeatPassword.insets	= new Insets(0, 0, 0, 5);
-			gbc_lblRepeatPassword.gridx		= 0;
-			gbc_lblRepeatPassword.gridy		= 2;
-		}
-		{
-			repeatPasswordField = new JPasswordField();
-			repeatPasswordField.setBorder(null);
-			gbc_repeatPasswordField			= new GridBagConstraints();
-			gbc_repeatPasswordField.fill	= GridBagConstraints.HORIZONTAL;
-			gbc_repeatPasswordField.gridx	= 1;
-			gbc_repeatPasswordField.gridy	= 2;
-		}
-		{
-			buttonPane = new JPanel();
 
-			registerText = new JTextPane();
+		lblUserName = new JLabel("Username:");
-			registerText.setEditable(false);
+		GridBagConstraints gbc_lblUserName = new GridBagConstraints();
-			registerText.setText("Register?");
+		gbc_lblUserName.anchor	= GridBagConstraints.EAST;
-			registerText.setFont(new Font("Arial", Font.BOLD, 12));
+		gbc_lblUserName.insets	= new Insets(0, 0, 5, 5);
-			registerText.setAlignmentX(LEFT_ALIGNMENT);
+		gbc_lblUserName.gridx	= 0;
-			buttonPane.add(registerText);
+		gbc_lblUserName.gridy	= 0;
+		contentPanel.add(lblUserName, gbc_lblUserName);
 
-			registerCheckBox = new JCheckBox();
+		textField = new JTextField();
-			registerCheckBox.setAlignmentX(LEFT_ALIGNMENT);
+		textField.setBorder(null);
-			registerCheckBox.addItemListener(new ItemListener() {
+		GridBagConstraints gbc_textField = new GridBagConstraints();
+		gbc_textField.insets	= new Insets(0, 0, 5, 0);
+		gbc_textField.fill		= GridBagConstraints.HORIZONTAL;
+		gbc_textField.gridx		= 1;
+		gbc_textField.gridy		= 0;
+		contentPanel.add(textField, gbc_textField);
+		textField.setColumns(10);
 
-				@Override
+		lblPassword = new JLabel("Password:");
-				public void itemStateChanged(ItemEvent e) {
+		GridBagConstraints gbc_lblPassword = new GridBagConstraints();
-					switch (e.getStateChange()) {
+		gbc_lblPassword.anchor	= GridBagConstraints.EAST;
-						case ItemEvent.SELECTED:
+		gbc_lblPassword.insets	= new Insets(0, 0, 0, 5);
-							contentPanel.add(lblRepeatPassword, gbc_lblRepeatPassword);
+		gbc_lblPassword.gridx	= 0;
-							contentPanel.add(repeatPasswordField, gbc_repeatPasswordField);
+		gbc_lblPassword.gridy	= 1;
-							setSize(338, 148);
+		contentPanel.add(lblPassword, gbc_lblPassword);
-							contentPanel.revalidate();
-							contentPanel.repaint();
-							break;
 
-						case ItemEvent.DESELECTED:
+		passwordField = new JPasswordField();
-							if (repeatPasswordField.getParent() == contentPanel) {
+		passwordField.setBorder(null);
-								contentPanel.remove(lblRepeatPassword);
+		GridBagConstraints gbc_passwordField = new GridBagConstraints();
-								contentPanel.remove(repeatPasswordField);
+		gbc_passwordField.fill	= GridBagConstraints.HORIZONTAL;
-								setSize(338, 123);
+		gbc_passwordField.gridx	= 1;
-								contentPanel.revalidate();
+		gbc_passwordField.gridy	= 1;
-								contentPanel.repaint();
+		contentPanel.add(passwordField, gbc_passwordField);
-							}
+
-							break;
+		lblRepeatPassword				= new JLabel("Repeat Password:");
+		gbc_lblRepeatPassword			= new GridBagConstraints();
+		gbc_lblRepeatPassword.anchor	= GridBagConstraints.EAST;
+		gbc_lblRepeatPassword.insets	= new Insets(0, 0, 0, 5);
+		gbc_lblRepeatPassword.gridx		= 0;
+		gbc_lblRepeatPassword.gridy		= 2;
+
+		repeatPasswordField				= new JPasswordField();
+		gbc_repeatPasswordField			= new GridBagConstraints();
+		gbc_repeatPasswordField.fill	= GridBagConstraints.HORIZONTAL;
+		gbc_repeatPasswordField.gridx	= 1;
+		gbc_repeatPasswordField.gridy	= 2;
+
+		errorMessage			= new JLabel();
+		gbc_errorMessage		= new GridBagConstraints();
+		gbc_errorMessage.gridx	= 1;
+		gbc_errorMessage.gridy	= 3;
+		gbc_errorMessage.fill	= GridBagConstraints.HORIZONTAL;
+		gbc_errorMessage.insets	= new Insets(5, 5, 5, 5);
+		errorMessage.setForeground(Color.RED);
+		errorMessage.setVisible(false);
+		contentPanel.add(errorMessage, gbc_errorMessage);
+
+		buttonPane = new JPanel();
+
+		registerText = new JTextPane();
+		registerText.setEditable(false);
+		registerText.setText("Register?");
+		registerText.setFont(new Font("Arial", Font.BOLD, 12));
+		registerText.setAlignmentX(LEFT_ALIGNMENT);
+		buttonPane.add(registerText);
+
+		registerCheckBox = new JCheckBox();
+		registerCheckBox.setAlignmentX(LEFT_ALIGNMENT);
+		registerCheckBox.addItemListener(e -> {
+			switch (e.getStateChange()) {
+				case ItemEvent.SELECTED:
+					contentPanel.add(lblRepeatPassword, gbc_lblRepeatPassword);
+					contentPanel.add(repeatPasswordField, gbc_repeatPasswordField);
+					setSize(338, 173);
+					break;
+
+				case ItemEvent.DESELECTED:
+					if (repeatPasswordField.getParent() == contentPanel) {
+						contentPanel.remove(lblRepeatPassword);
+						contentPanel.remove(repeatPasswordField);
+						setSize(338, 148);
 					}
-				}
+					break;
-			});
+			}
-			buttonPane.add(registerCheckBox);
+			contentPanel.revalidate();
+			contentPanel.repaint();
+		});
+		buttonPane.add(registerCheckBox);
 
-			buttonPane.setLayout(new FlowLayout(FlowLayout.RIGHT));
+		buttonPane.setLayout(new FlowLayout(FlowLayout.RIGHT));
-			getContentPane().add(buttonPane, BorderLayout.SOUTH);
+		getContentPane().add(buttonPane, BorderLayout.SOUTH);
-			{
+		okButton = new PrimaryButton("OK");
-				okButton = new PrimaryButton("OK");
+		okButton.setActionCommand("OK");
-				okButton.addActionListener((evt) -> {
+		buttonPane.add(okButton);
-					try {
+		getRootPane().setDefaultButton(okButton);
-						if (registerCheckBox.isSelected()) {
+
-							if (Arrays.equals(passwordField.getPassword(), repeatPasswordField.getPassword())) {
+		cancelButton = new PrimaryButton("Cancel");
-								credentials = new LoginCredentials(textField.getText(), passwordField.getPassword(), true);
+		cancelButton.setActionCommand("Cancel");
-								dispose();
+		buttonPane.add(cancelButton);
-							} else {
-								JOptionPane.showMessageDialog(this, "The repeated password is unequal to the origional password!");
-								passwordField.setText(null);
-								repeatPasswordField.setText(null);
-							}
-						} else {
-							credentials = new LoginCredentials(textField.getText(), passwordField.getPassword(), false);
-							dispose();
-						}
-					} catch (NoSuchAlgorithmException e) {
-						e.printStackTrace();
-					}
-				});
-				okButton.setActionCommand("OK");
-				buttonPane.add(okButton);
-				getRootPane().setDefaultButton(okButton);
-			}
-			{
-				cancelButton = new PrimaryButton("Cancel");
-				cancelButton.addActionListener((evt) -> dispose());
-				cancelButton.setActionCommand("Cancel");
-				buttonPane.add(cancelButton);
-			}
-		}
 		setTheme();
 
-		setModal(true);
+		setModalityType(Dialog.DEFAULT_MODALITY_TYPE);
-		setVisible(true);
+
+		EventBus.getInstance().register(HandshakeSuccessfulEvent.class, evt -> dispose());
+	}
+
+	/**
+	 * Resets the text stored in the password fields.
+	 *
+	 * @since Envoy v0.3-alpha
+	 */
+	private void clearPasswordFields() {
+		passwordField.setText(null);
+		repeatPasswordField.setText(null);
 	}
 
 	private void setTheme() {
@@ -238,11 +320,4 @@ public class LoginDialog extends JDialog {
 		cancelButton.setBackground(theme.getInteractableBackgroundColor());
 		cancelButton.setForeground(theme.getInteractableForegroundColor());
 	}
-
-	/**
-	 * @return the {@link LoginCredentials} entered by the user, or {@code null} if
-	 *         the dialog has been cancelled
-	 * @since Envoy v0.3-alpha
-	 */
-	public LoginCredentials getCredentials() { return credentials; }
 }

src/main/java/envoy/client/ui/MessageListRenderer.java

@@ -5,7 +5,7 @@ import java.text.SimpleDateFormat;
 
 import javax.swing.*;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 import envoy.client.ui.list.ComponentList;
 import envoy.client.ui.list.ComponentListCellRenderer;
 import envoy.data.Message;

src/main/java/envoy/client/ui/PrimaryScrollBar.java

@@ -12,7 +12,7 @@ import javax.swing.JComponent;
 import javax.swing.JScrollBar;
 import javax.swing.plaf.basic.BasicScrollBarUI;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 
 /**
  * Project: <strong>envoy-client</strong><br>

src/main/java/envoy/client/ui/PrimaryToggleSwitch.java

@@ -5,8 +5,8 @@ import java.awt.Graphics;
 
 import javax.swing.JButton;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
-import envoy.client.SettingsItem;
+import envoy.client.data.SettingsItem;
 
 /**
  * This component can be used to toggle between two options. This will change

src/main/java/envoy/client/ui/Startup.java

@@ -11,14 +11,11 @@ import javax.swing.JFrame;
 import javax.swing.JOptionPane;
 import javax.swing.SwingUtilities;
 
-import envoy.client.Settings;
 import envoy.client.data.*;
 import envoy.client.net.Client;
 import envoy.client.net.WriteProxy;
 import envoy.client.util.EnvoyLog;
-import envoy.data.LoginCredentials;
 import envoy.data.Message;
-import envoy.data.User;
 import envoy.exception.EnvoyException;
 
 /**
@@ -63,7 +60,7 @@ public class Startup {
 			if (args.length > 0) config.load(args);
 
 			// Check if all mandatory configuration values have been initialized
-			if (!config.isInitialized()) throw new EnvoyException("Server or port are not defined");
+			if (!config.isInitialized()) throw new EnvoyException("Configuration is not fully initialized");
 		} catch (Exception e) {
 			JOptionPane
 				.showMessageDialog(null, "Error loading configuration values:\n" + e.toString(), "Configuration error", JOptionPane.ERROR_MESSAGE);
@@ -75,14 +72,6 @@ public class Startup {
 		EnvoyLog.setFileLevelBarrier(config.getFileLevelBarrier());
 		EnvoyLog.setConsoleLevelBarrier(config.getConsoleLevelBarrier());
 
-		// Acquire login credentials
-		LoginCredentials credentials = config.hasLoginCredentials() ? config.getLoginCredentials() : new LoginDialog().getCredentials();
-
-		if (credentials == null) {
-			logger.info("The login process has been aborted by the user. Exiting...");
-			System.exit(0);
-		}
-
 		// Initialize the local database
 		LocalDb localDb;
 		if (config.isIgnoreLocalDB()) {
@@ -96,40 +85,18 @@ public class Startup {
 		} catch (IOException e3) {
 			logger.log(Level.SEVERE, "Could not initialize local database", e3);
 			JOptionPane
-				.showMessageDialog(null, "Could not initialize local database!\n" + e3.toString(), "Local database error", JOptionPane.ERROR_MESSAGE);
+				.showMessageDialog(null, "Could not initialize local database!\n" + e3, "Local database error", JOptionPane.ERROR_MESSAGE);
 			System.exit(1);
 			return;
 		}
 
-		SwingUtilities.invokeLater(() -> chatWindow.setVisible(true));
+		// Initialize client and unread message cache
-
-		// Acquire the client user (with ID) either from the server or from the local
-		// database, which triggers offline mode
 		Client			client	= new Client();
 		Cache<Message>	cache	= new Cache<>();
-		try {
+
-			// Try entering online mode first
+		// Try to connect to the server
-			localDb.loadIdGenerator();
+		new LoginDialog(client, localDb, cache);
-			client.onlineInit(credentials, localDb, cache);
+		SwingUtilities.invokeLater(() -> chatWindow.setVisible(true));
-		} catch (Exception e1) {
-			logger.warning("Could not connect to server. Trying offline mode...");
-			e1.printStackTrace();
-			try {
-				// Try entering offline mode
-				localDb.loadUsers();
-				User clientUser = localDb.getUsers().get(credentials.getName());
-				if (clientUser == null) throw new EnvoyException("Could not enter offline mode: user name unknown");
-				client.setSender(clientUser);
-				JOptionPane.showMessageDialog(null,
-						"A connection to the server could not be established. Starting in offline mode.\n" + e1,
-						"Connection error",
-						JOptionPane.WARNING_MESSAGE);
-			} catch (Exception e2) {
-				JOptionPane.showMessageDialog(null, e2.toString(), "Client error", JOptionPane.ERROR_MESSAGE);
-				System.exit(1);
-				return;
-			}
-		}
 
 		// Set client user in local database
 		localDb.setUser(client.getSender());

src/main/java/envoy/client/ui/UserListRenderer.java

@@ -7,7 +7,7 @@ import javax.swing.JLabel;
 import javax.swing.JList;
 import javax.swing.ListCellRenderer;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 import envoy.data.User;
 import envoy.data.User.UserStatus;
 

src/main/java/envoy/client/ui/settings/GeneralSettingsPanel.java

@@ -10,8 +10,8 @@ import java.util.logging.Logger;
 import javax.swing.JComponent;
 import javax.swing.JTextPane;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
-import envoy.client.SettingsItem;
+import envoy.client.data.SettingsItem;
 import envoy.client.ui.Theme;
 import envoy.client.util.EnvoyLog;
 

src/main/java/envoy/client/ui/settings/NewThemeScreen.java

@@ -7,7 +7,7 @@ import javax.swing.JDialog;
 import javax.swing.JPanel;
 import javax.swing.JTextPane;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 import envoy.client.ui.PrimaryButton;
 import envoy.client.ui.PrimaryTextArea;
 import envoy.client.ui.Theme;

src/main/java/envoy/client/ui/settings/SettingsScreen.java

@@ -9,7 +9,7 @@ import java.util.logging.Logger;
 
 import javax.swing.*;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 import envoy.client.event.ThemeChangeEvent;
 import envoy.client.ui.PrimaryButton;
 import envoy.client.ui.Theme;

src/main/java/envoy/client/ui/settings/ThemeCustomizationPanel.java

@@ -9,7 +9,7 @@ import java.util.logging.Logger;
 
 import javax.swing.*;
 
-import envoy.client.Settings;
+import envoy.client.data.Settings;
 import envoy.client.event.ThemeChangeEvent;
 import envoy.client.ui.Color;
 import envoy.client.ui.Theme;