Invoking a method from a java class to a jsp file

Question

Maybe i'm going through a very basic error, but as i've looked for in some forums and nothing found decided to post. So let's go to the problem.
Well, i have a form in a jsp file, it's basicaly html, but as i need some select boxes populated with data from the database i decided to create some methods in java classes. This is the point.
My method receive some attributes, like the table and colums names, the name of the select box and the HttpServletResponse object.
So after making all the database process. The method is supposed to write the result through the out.println(); object
It goes everything all right except that the method seems to be called first than the html code coz' my select boxes comes above the head in the begin of the page and was supposed to come in the middle.
part of the code:
package pacote;
import java.packages.*
public class Class{
public void metodo(HttpServletResponse response, String tableName, String column name, String selectName){
PrintWriter out = response.getWriter();
openConnection();
//After making the query stuff
//caso n�o haja nada na consulta
     if(rst == null)
     out.println("N�o h� registros.");
     else{
     out.println( "<select name='" +SelectName + "' id='" +SelectName + "' class=\"input_ob\" >");
     out.println( "<option value=''>Escolha: "+objeto+"</option>");
     //fill the select body with options; A while that sweap the resultSet and use the out object to write the results          
     getSelectBody(out,rst, selectValue);
}This method is called this way:
<tr valign="baseline">
    <td nowrap align="right">Grupo</td>
    <jsp:useBean id="m" scope="page" class="pacote.Class" />
        <td>
          <%
          try{
               m.metodo(response, "tabela","grupo","id_grupo);
          } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
                    %></td>I'd like to know what i'm missing here. why the answer doesn't go in the place It's supposed to go.
any answer will be greatly apreciated

Answer 1

The issue is caused because you are using the response to get the writer directly.
The JSP has gotten the same writer, but has wrapped it in a JSPWriter class. That class has got a buffer.
So it writes the beginning html to the JSPWriter buffer.
You write your stuff to the response writer - gets sent to the output.
It writes more stuff to the JSPWriter buffer, then flushes that buffer - at which point all the text written into the JSP writer now gets added to the response.
You see how your code is coming out first?
Solution - instead of getting the writer from the response, pass the writer into your method (maybe instead of response if you don't use response for anything else)
public void metodo(Writer jspWriter, String tableName, String column name, String selectName){
  PrintWriter out = new PrintWriter(jspWriter);
  ...That means that you will be writing to the same writer, and the text should come out in sequence.
Cheers,
evnafets