Using java class and variables declared in java file in jsp

hi everyone
i m trying to seperate business logic form web layer. i don't know i am doing in a right way or not.
i wanted to access my own java class and its variables in jsp.
for this i created java file like this
package ris;
import java.sql.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class NewClass{
 public static void main(String args[]){
 Connection con = null;
 ResultSet rs=null;
 Statement smt=null;
 try{
 Class.forName("com.mysql.jdbc.Driver").newInstance();
 con=DriverManager.getConnection("jdbc:mysql:///net","root", "anthony111");
 smt=con.createStatement();
 rs= smt.executeQuery("SELECT * FROM emp");
 while(rs.next()){
 String str = rs.getString("Name");
 }catch( Exception e){
 String msg="Exception:"+e.getMessage();
 }finally {
 try {
 if(con != null)
 con.close();
 } catch(SQLException e) {}
}next i created a jsp where i want to access String str defined in java class above.
<%--
 Document : fisrt
 Created on : Jul 25, 2009, 3:00:38 PM
 Author : REiSHI
--%>
<%@page import="ris.NewClass"%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
 "http://www.w3.org/TR/html4/loose.dtd">
<html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 <title>JSP Page</title>
 </head>
 <body>
 <h1><%=str%></h1>
 </body>
</html>I wanted to print the name field extracted from database by ResultSet.
but it gives error cannot find symbol str.
please help me to find right way to do this.
i am using netbeans ide.

Very bad approach
1) Think if your table contains more than one NAMEs then you will get only the last one with your code.
2) Your String is declared as local variable in the method.
3) You have not created any object of NewClass nor called the method in JSP page. Then who will call the method to run sql?
4) Your NewClass contains main method which will not work in web application, it's not standalone desktop application so remove main.
Better create an ArrayList and then call the method of NewClass and then store the data into ArrayList and return the ArrayList.
It should look like
{code:java}
package ris;
import java.sql.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class NewClass{
 public static ArrayList getNames(){
 Connection con = null;
 ResultSet rs=null;
 Statement smt=null;
 ArrayList nameList = new ArrayList();
 try{
 Class.forName("com.mysql.jdbc.Driver").newInstance();
 con=DriverManager.getConnection("jdbc:mysql:///net","root", "anthony111");
 smt=con.createStatement();
 rs= smt.executeQuery("SELECT * FROM emp");
 while(rs.next()){
 nameList.add(rs.getString("Name"));
 return nameList;
 }catch( Exception e){
 String msg="Exception:"+e.getMessage();
 </code><code class="jive-code jive-java">return nameList;</code><code class="jive-code jive-java">
 }finally {
 try {
 if(con != null)
 con.close();
 } catch(SQLException e) {}
 </code><code>return nameList;</code>
<code class="jive-code jive-java"> }

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