public void ucitajDrajver() {
        try {
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException ex) {
            Logger.getLogger(DBBroker.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void otvoriKonekciju() {
        String url = "jdbc:mysql://localhost:3306/prosoftjan18";
        String dbuser = "root";
        String dbpassword = "";
        try {
            konekcija = DriverManager.getConnection(url, dbuser, dbpassword);
            konekcija.setAutoCommit(false);
            System.out.println("otvori");
        } catch (SQLException ex) {
            Logger.getLogger(DBBroker.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void zatvoriKonenciju() {
        try {
            konekcija.close();
        } catch (SQLException ex) {
            Logger.getLogger(DBBroker.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void commit() {
        try {
            konekcija.commit();
        } catch (SQLException ex) {
            Logger.getLogger(DBBroker.class.getName()).log(Level.SEVERE, null, ex);
        }
    }

    public void rollback() {
        try {
            konekcija.rollback();
        } catch (SQLException ex) {
            Logger.getLogger(DBBroker.class.getName()).log(Level.SEVERE, null, ex);
        }
    }