JComboBox comboTeam;
    JComboBox comboPlayer;
    JButton button;
    Connection con = null;
    Statement st = null;
    ResultSet rs = null;
    /* String[] playerString = {"TeamCaptain", "Striker1", "Striker2", "Striker3", "Striker4", "Midfielder1", "Midfielder2", "Midfielder3", "Defence1", "Defence2", "Defence3", "Goalkeeper", "Manager", "Coach"};
     */
    comboTeam = new JComboBox();
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 1;
    paneDelp.add(comboTeam, c);
    String APlayer = (String) comboTeam.getSelectedItem();

    comboPlayer = new JComboBox(/*playerString*/);
    c.fill = GridBagConstraints.HORIZONTAL;
    c.gridx = 0;
    c.gridy = 2;
    paneDelp.add(comboPlayer, c);

try {
        con = DriverManager.getConnection("jdbc:derby://localhost:1527/" + "jfl", "jfl", "jfl");
        st = con.createStatement();
        String s = "SELECT Teamname from JFL.TEAMS";
        rs = st.executeQuery(s);
        while (rs.next()) {
            comboTeam.addItem(rs.getString(1));
        }
    } catch (Exception f) {
        JOptionPane.showMessageDialog(null, "ERROR");
    } finally {
        try {
            st.close();
            rs.close();
            con.close();
        } catch (Exception f) {
            JOptionPane.showMessageDialog(null, "ERROR CLOSE");
        }
    }

try {
        con = DriverManager.getConnection("jdbc:derby://localhost:1527/" + "jfl", "jfl", "jfl");
        st = con.createStatement();
        String s = "SELECT MANAGER FROM JFL.TEAMS WHERE  Teamname=" + APlayer;
        rs = st.executeQuery(s);
        while (rs.next()) {
            comboPlayer.addItem(rs.getString(1));
        }
    } catch (Exception f) {
        JOptionPane.showMessageDialog(null, "EROR");
    } finally {
        try {
            st.close();
            rs.close();
            con.close();
        } catch (Exception f) {
            JOptionPane.showMessageDialog(null, "ERROR CLOSE");
        }
    }