Added GUI window for user login

src/main/java/LoginGUI.java

@@ -0,0 +1,29 @@
+import javax.swing.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.util.List;
+
+public class LoginGUI extends JFrame implements ActionListener {
+
+    public LoginGUI() {
+        setTitle("Login");
+        setSize(300, 150);
+        setDefaultCloseOperation(EXIT_ON_CLOSE);
+        setLayout(null);
+
+        
+    }
+
+    @Override
+    public void actionPerformed(ActionEvent e) {
+        
+    }
+
+
+    public static void main(String[] args) {
+        SwingUtilities.invokeLater(() -> {
+            LoginGUI loginGUI = new LoginGUI();
+            loginGUI.setVisible(true);
+        });
+    }
+}

user.json

@@ -10,5 +10,23 @@
     "userName": "asd1",
     "password": "123456",
     "birthday": "1"
+  },
+  {
+    "id": "b54391dc-c06b-496c-828a-501f9a182cf9",
+    "userName": "new user",
+    "password": "123456",
+    "birthday": "1"
+  },
+  {
+    "id": "6db2ea00-246d-4604-bef2-0875c3cb550e",
+    "userName": "Another Test User",
+    "password": "TestPasswort123",
+    "birthday": "01.01.2000"
+  },
+  {
+    "id": "864695a6-8037-41e5-9f0e-4b92744b2113",
+    "userName": "Another Test User",
+    "password": "TestPasswort123",
+    "birthday": "01.01.2000"
   }
 ]