Java File and JSP Page

I am to create a link verification program -- a simple java file with the database connection & some business logic and a JSP page that instantiates the my java file. It won't work. Everytime I run the jsp page, it gives me java.lang.NullPointerException. Can anyone give me some directions? The web server I am using is JRun.
Thank you
Below are my code:
JSP Page:
<%--      Verify Links
--%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<%@ page import="java.sql.*" %>
<%@ page import="java.net.*" %>
<%@ page import="pro.*" %>
<html>
<head>
<title>Results</title>
</head>
<body>
<%
try{
LinkConnection newconn = new LinkConnection();
newconn.initialize();
newconn.query();
newconn.close();
}catch (ClassNotFoundException cnfe)
out.println(cnfe);
catch (SQLException sqle)
out.println(sqle);
catch (NullPointerException npe)
out.println(npe);
%>
</body>
</html>
Java Code:
package pro;
import java.io.*;
import java.sql.*;
import java.net.*;
public class LinkConnection {
Connection con;
ResultSet RS;
Statement Stmt;
public void initialize() throws SQLException, ClassNotFoundException
Class.forName("oracle.jdbc.driver.OracleDriver");
con = DriverManager.getConnection("XXXX", "XXXX", "XXXX");
public void query() throws SQLException
Statement Stmt=con.createStatement();
String strSQL="Select guideline_name, guideline_url from pgt_guidelines";
ResultSet RS=Stmt.executeQuery(strSQL);
while (RS.next())
String guidelinename = RS.getString("guideline_name");
String guidelineurl = ("http://" + RS.getString("guideline_url"));
try {
URL url = new URL(guidelineurl);
HttpURLConnection link=(HttpURLConnection)url.openConnection();
System.out.println("<font color='blue'>");
System.out.println(guidelinename);
System.out.println("<br>");
System.out.println(guidelineurl);
System.out.println("</font>");
System.out.println("<font color='red'>");
System.out.println(link.getResponseCode());
System.out.println("</font>");
System.out.println("<br />");
          }catch (Exception e)
          {System.out.println("<font color='yellow'>Error Link </font>")
public void close() throws SQLException {
RS.close();
Stmt.close();
con.close();

i'm having the same problem, what is the solution to this
A Servlet Exception Has Occurred
java.lang.NullPointerException
     at test.Lesson.runSql(Lesson.java:80)
===== Lesson.java file =====
package test;
import java.sql.* ;
import java.io.Serializable;
public class Lesson {
     public Lesson( ) { }
//Line 9
     public String runSql ( ) {
          String browserOutput = "";
          Connection sqlca = null;
          Statement sqlStatement = null;
          ResultSet myResultSet = null;
//Line 16
          /* Connect to database, run SQL and produce output */
          try {
               /* Connection to the database */
               Class.forName("org.gjt.mm.mysql.Driver").newInstance();
               String theDatabase ="jdbc:mysql://localhost/employee";
               sqlca = DriverManager.getConnection(theDatabase,"usr","pwd");
//Line 24
               /* Construct and execute the sql, positioning before the
               first row in the result set */
               sqlStatement = sqlca.createStatement();
               myResultSet = sqlStatement.executeQuery
//Line 29
               ("select emp_id, " +
                    "emp_lname, " +
                    "city, " +
                    "state," +
                    "zip_code, " +
                    "emp_fname " +
                    "from employee " +
                    "where emp_id < 250 " +
                    "order by emp_lname, emp_fname");
//Line 39
               /* Construct the heading for the table */
               browserOutput =
                    "<div align=left>"+
                    "<table border=0 align=left width=520>" +
                    "<caption><i><b>" +
                    "Employee Listing</b></i></caption>" ;
//Line 46
               /* Construct the column headings for the table */
               browserOutput +=
                    "<th align=left>Emp_id</th>" +
                    "<th>First Name</th>" +
                    "<th>Last Name</th>" +
                    "<th>City</th>" +
                    "<th>State</th>" +
                    "<th>Zip</th>" ;
//Line 55
               /* Move to next row and & its contents to the html output */
               while(myResultSet.next()) {
                    browserOutput += "<TR><TD>" +
               myResultSet.getObject("emp_id").toString() + "</TD><TD>" +
               myResultSet.getObject("emp_fname").toString()+"</TD><TD>" +
               myResultSet.getObject("emp_lname").toString() + "</TD><TD>" +
               myResultSet.getObject("city").toString() + "</TD><TD>" +
               myResultSet.getObject("state").toString() + "</TD><TD>" +
               myResultSet.getObject("zip_code").toString() + "</TD></TR>" ;
//Line 66
               }//end of while
               sqlStatement.close();
               sqlca.close();
          }//end of try
          catch (SQLException e) {
//Line 72
               browserOutput = " Error: SQLException: " + e.getMessage();
               browserOutput= " Error: SQLState: " + e.getSQLState();
               browserOutput= " VendorError: " + e.getErrorCode();
          }//end of SQLException
          catch (Exception e) {
               browserOutput = " Error: JDBC Class creation: " + e.getMessage();
          }//end of Exception
/**Line 80**/     finally {
               try { sqlca.close(); }
               catch(SQLException e) {
               browserOutput = " Error: Closing connection: " + e.getMessage();
          }//end of finally
     /* Complete the html and return it to the Java Server Page */
     browserOutput += "</table>" + "</div>" ;
     return browserOutput;
     } //end of runSql
}//end of Lesson

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