public Connection login() {
		try {
			Class.forName("com.mysql.jdbc.Driver");
		} catch (ClassNotFoundException e1) {
			System.out.println("Connection registration error");
			e1.printStackTrace();
		}
		Properties connectionProps = new Properties();
		connectionProps.put("user", "librarian");
		connectionProps.put("password", "librarian");
		try {
			Main.setConnection(DriverManager.getConnection("jdbc:mysql://localhost:3306/javabase", connectionProps));
			connected = true;
		} catch (SQLException e) {
			Logger.getLogger(Login.class.getName()).log(Level.SEVERE, "Opening connection exception", e);
		}
		return Main.getConnection();
}