login GUI + abmelde button funktioniert

LoginGUI.java

@@ -34,6 +34,7 @@ public class LoginGUI extends JDialog implements ActionListener {
 		setBounds(100, 100, 251, 220);
 		setLocationRelativeTo(null);
 		getContentPane().setLayout(new BorderLayout());
+		setDefaultCloseOperation(DISPOSE_ON_CLOSE);
 		contentPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
 		getContentPane().add(contentPanel, BorderLayout.CENTER);
 		contentPanel.setLayout(null);
@@ -90,9 +91,8 @@ public class LoginGUI extends JDialog implements ActionListener {
 	public void actionPerformed(ActionEvent e) {
 		if (e.getActionCommand().equals("OK")) {
 			app.start(address.getText(), 110, user.getText(), new String(pw.getPassword()));
-			dispose();
 		} else if (e.getActionCommand().equals("Cancel")) {
-			System.out.println("Cancel");
+			dispose();
 		}
 	}
 }

MyMail.java

@@ -1,3 +1,4 @@
+import javax.swing.JOptionPane;
 
 public class MyMail {
 
@@ -27,20 +28,33 @@ public class MyMail {
 
 	private String lastError;
 	
-	private LoginGUI loginGUI;
+	private LoginGUI login;
 
 	/**
 	 * Verbindet zu einem lokalen POP3-Server.
 	 */
 	public MyMail() {
-		loginGUI = new LoginGUI(this);
+		login = new LoginGUI(this);
 	}
 
 	public void start(String pIP, int pPort, String pUser, String pPassword) {
+		
 		ip = pIP;
 		port = pPort;
 		user = pUser;
 		password = pPassword;
+		
+		if (!connectToServer()) {
+			JOptionPane.showMessageDialog(null, lastError, "Fehler", JOptionPane.ERROR_MESSAGE);
+			return;
+		}
+		if (!login()) {
+			JOptionPane.showMessageDialog(null, lastError, "Fehler", JOptionPane.ERROR_MESSAGE);
+			return;
+		}
+		con.send("QUIT");
+		con.close();
+		login.dispose();
 
 		// GUI erstellen und Status setzen.
 		gui = new MyMailGUI(this);
@@ -108,14 +122,14 @@ public class MyMail {
 		con.send("USER " + user);
 		mes = con.receive();
 		if (mes == null || mes.startsWith("-ERR")) {
-			lastError = "Ungueltiger Benutzername!";
+			lastError = "Ungültiger Benutzername!";
 			return false;
 		}
 		// PASS Kommando senden und Antwort prüfen
 		con.send("PASS " + password);
 		mes = con.receive();
 		if (mes == null || mes.startsWith("-ERR")) {
-			lastError = "Ungueltiges Passwort!";
+			lastError = "Ungültiges Passwort!";
 			return false;
 		}
 		// Anmeldung war erfolgreich
@@ -326,4 +340,8 @@ public class MyMail {
 		gui.removeMailFromList(pMail);
 	}
 
+	public void switchUser() {
+		login = new LoginGUI(this);
+	}
+
 }

MyMailGUI.java

@@ -22,7 +22,7 @@ public class MyMailGUI extends JFrame implements ActionListener, ListSelectionLi
 
     private JLabel jlStatusText;
 
-    private JButton jbReload, jbDelete, jbNew, jbReply, jbSettings;
+    private JButton jbReload, jbDelete, jbNew, jbReply, jbSettings, jbSwitchUser;
 
     private JTable jtMaillist;
 
@@ -100,6 +100,9 @@ public class MyMailGUI extends JFrame implements ActionListener, ListSelectionLi
             app.getAllMails();
         } else if( e.getActionCommand().equals("delete") ) {
             app.deleteMail(mails.get(jtMaillist.getSelectedRow()));
+        } else if (e.getActionCommand().equals("switchUser")) {
+        	app.switchUser();
+        	dispose();
         }
     }
 
@@ -144,6 +147,11 @@ public class MyMailGUI extends JFrame implements ActionListener, ListSelectionLi
         jbDelete.addActionListener(this);
         jbDelete.setIcon(loadImageIcon("email_delete.png"));
         jpSidebar.add(jbDelete);
+        
+        jbSwitchUser = new JButton("Abmelden");
+        jbSwitchUser.setActionCommand("switchUser");
+        jbSwitchUser.addActionListener(this);
+        jpSidebar.add(jbSwitchUser);
 
         jbSettings = new JButton("Einstellungen");
         jbSettings.setActionCommand("settings");