URGENT! Java Bean Query

Question

I am using Tomcat 3.1 and MySQL database for an application I am designing. Below is the code for a java bean that registers users details. The code compiles correctly, but I would like to know if there is any code that I might have left out? What changes should I make to make it more user friendly?
I do not want to use servlets, as they are very difficult to setup.
REGISTRATION.JAVA
package gcd;
import java.sql.*;
import java.util.*;
import java.lang.*;
import java.awt.*;
import java.text.*;
import java.io.*;
import com.mysql.jdbc.*;
public class Registration
     public Registration(){}
String first_name;
String last_name;
String role;
String email;
String error;
java.sql.Connection con;
public void setFirstName( String value )
first_name = value;
public void setLastName( String value )
last_name = value;
public void setRole( String value )
role = value;
public void setEmail( String value )
email = value;
public String getFirstName()
return first_name;
public String getLastName()
     return last_name;
public String getRole()
     return role;
public String getEmail()
     return email;
     public void connect() throws ClassNotFoundException, SQLException, Exception
try
System.setProperty("jdbc.drivers", "com.mysql.jdbc.Driver");
Class.forName("com.mysql.jdbc.Driver").newInstance();
con = DriverManager.getConnection("jdbc:mysql://localhost/gcdBB_db","","");
catch (ClassNotFoundException e)
error = "ClassNotFoundException: Could not locate DB driver.";
throw new ClassNotFoundException(error);
catch (SQLException e)
error = "SQLException: Could not connect to database.";
throw new SQLException(error);
catch (Exception e)
error = "Exception: An unknown error occured while connecting to database.";
throw new Exception (error);
     public void disconnect() throws SQLException
try
if(con != null)
con.close();
catch (SQLException e)
error = ("SQLException: Unable to close the database connection.");
throw new SQLException(error);
public java.sql.ResultSet validateRegistration(String firstname, String lastname, String role, String email) throws SQLException, Exception
java.sql.ResultSet rs = null;
try
String queryString = ("INSERT INTO registration (firstname,lastname,role,email) VALUES ('" + firstname + "','" + lastname + "','" + role + "','" + email + "';");
java.sql.Statement stmt = con.createStatement();
rs = stmt.executeQuery(queryString);
catch (SQLException e)
error = "SQLException: Could not execute the query.";
throw new SQLException(error);
catch (Exception e)
error = "An exception occured while retrieving users.";
throw new Exception(error);
return rs;
Thanks,
Niall

Answer 1

in JavaBean class:
The setting/getting method should be matched with the first letter capitalized. ie.
String firstName;
String lastName;
public void setFirstName(String value) { firstName = value ; }
public String getFirstName() { return firstName; }
public void setLastName(String value) { lastName = value ; }
public String getLastName() { return lastName; }
String role and email coded correctly.
remember: put your bean in package and call from package.