Please explain the implementation of class methods in JSP from a servlet?

Question

Java

Guys, please clarify the following: in my web application, there are three simple queries to the database SELECT, INSERT and UPDATE.

Accordingly, I have three classes with different functionality to the database.

SELECT example:

class DirectorSelect{
  public String selectDirectors() {
    Connection koneksi = null;
    Statement stat = null;
    String str = "";
    try{
        Class.forName("com.mysql.jdbc.Driver");
        koneksi = DriverManager.getConnection("jdbc:mysql://localhost/dbizza","root","");
        stat = koneksi.createStatement();
        ResultSet hasil = stat.executeQuery("SELECT * FROM directors");
        while (hasil.next()) {
            str = str + (hasil.getInt(1) + "\t" + hasil.getString(2)+ "\t" + hasil.getString(3)+ "\t" + hasil.getDate(4)+ "\t" + hasil.getString(5));
        }
        stat.close();
        koneksi.close();
    } catch (SQLException sqle) {
        str = "SQLException error";
    } catch (ClassNotFoundException cnfe) {
        str = "ClassNotFoundException error";
    }
    return str;
 }

And one servlet:

public class DirectorsViewServlet extends HttpServlet {

  public void doGet(HttpServletRequest req, HttpServletResponse res) throws IOException, ServletException {
    res.setContentType("text/html");
    PrintWriter out = res.getWriter();
    DirectorSelect ds = new DirectorSelect();
    out.println(ds.selectDirectors());
  }

  public void doPost(HttpServletRequest req, HttpServletResponse res) throws IOException, ServletException {
    doGet(req, res);
  }
}

Question 1 how in servlet using

request.setAttribute();
request.getRequestDispatcher("index.jsp").forward(request, response);

pass method value to JSP.

Question number 2 how to implement the remaining two methods of the two classes in the servlet, but that they would not be executed all together, as in the

example:

request.setAttribute("p", new PrintText());
request.setAttribute("s", new ShowText());
request.setAttribute("e", new ShowText1());
request.getRequestDispatcher("index.jsp").forward(request, response);

but only on request, possibly sent to different jsp pages. Or please clarify that my understanding of the logic of the servlet is not correct? Thank you all very much.