how to return value from java class to Servlet in java

Question

I have java class LoginValidation and Servlet Login ,am passing values from servlet to java class,but am not getting return values..from servlet to java class...

//normal java class LoginValidation

public class LoginValidation {

    String userid="";
    String password="";
    String que="";
    Connection dbConnection = null;
    PreparedStatement pst=null;
    ResultSet rs=null;
    String userid1="";
    String password1="";
    int pan1=0;

    public long valiDate(String userid ,String password){


        long flag = 0l; 
        this.password=password;
        this.userid=userid;

        dbConnection = JDBCConnection.getDBConnection();
        que="select * from shivu";
        try {
            pst = dbConnection.prepareStatement(que);
            rs=pst.executeQuery();

            while(rs.next()){
             userid1=rs.getString(3);
             password1=rs.getString(2);
             pan1=rs.getInt(8);

             if ((userid.equals(userid1)) && (password.equals(password1))){
                    flag = pan1;    

             }else{
                 flag = 0;

             }   
             }

        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        return flag;
    }
}

//Servlet Login

public class Login extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub



        String userid=request.getParameter("userid");

        String password=request.getParameter("password");

        LoginValidation lv=new LoginValidation();

        System.out.println("control flow");

        long i=lv.valiDate(userid,password);

        System.out.println(i);

        if(i>=1){       

            System.out.println("control flow inside method call");

            HttpSession session = request.getSession();

            if (session != null)
                session.setAttribute("pan", i);

            response.sendRedirect("welcome.jsp");
        }
        else
        {

            System.out.println("Username or Password incorrect");
            response.sendRedirect("login1.jsp");
        }




    }

}

Answer 1

you can print and see the values inside valiDate method.

        while(rs.next()){
         userid1=rs.getString(3);
         password1=rs.getString(2);
         pan1=rs.getInt(8);

         // print userid, userid1, password, password1, pan1

         if ((userid.equals(userid1)) && (password.equals(password1))){
                flag = pan1;    

         }else{
             flag = 0;

         }   
         }