private static final String DDBC_DRIVER = "com.mysql.jdbc.Driver";
private static final String DB_URL = "jdbc:mysql://localhost:3306";

private static final String USER = "root";
private static final String PASS = "1234";

public static void conecta() throws ClassNotFoundException, SQLException {
    try {
        conexion = DriverManager.getConnection(DB_URL, USER, PASS);

        stmt = conexion.createStatement();


    } catch (SQLException se) {
        se.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public void llenarComboBD() throws SQLException{
    MySQL.ejecutaConsulta("show databases");
    while(MySQL.getRs().next()){
        System.out.println(MySQL.getRs().getString(0));
    }
}

public static void ejecutaConsulta(String consulta) {
    try {
        rs = stmt.executeQuery(consulta);
        meta = rs.getMetaData();
    } catch (SQLException ex) {
        Logger.getLogger(MySQL.class.getName()).log(Level.SEVERE, null, ex);
    }
}

public void llenarComboBD() throws SQLException, ClassNotFoundException{
        MySQL.conecta("jdbc:mysql://localhost:3306/", "root", "1234");
        MySQL.ejecutaConsulta("show databases");
        ResultSet rs = MySQL.getRs();
        //MySQL.getMeta();

        while(rs.next()){
            //String bd = rs.getString(1);
            jcBD.add());
        }

}

while(rs.next()){
        //String bd = rs.getString(1);
        jcBD.add());
    }