Erro struts

package br.com.ricardo.jdbc.dao;

import br.com.ricardo.jdbc.jdbc.ConnectionFactory;
import br.com.ricardo.jdbc.modelo.*;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;

public class ContatoDAO {

   // a conexão com o banco de dados
   private Connection connection;

   // construtor que recebe a conex�o
   public ContatoDAO(Connection con) {
      this.connection = con;
   }

   public ContatoDAO() throws SQLException {
      this.connection = ConnectionFactory.getConnection();
   }

   public void adiciona(Contato contato) throws SQLException {

      // prepared statement para inser��o
      PreparedStatement stmt = this.connection.prepareStatement("insert into contatos (nome,email,endereco) values (?, ?, ?)");

      // seta os valores
      stmt.setString(1, contato.getNome());
      stmt.setString(2, contato.getEmail());
      stmt.setString(3, contato.getEndereco());

      // executa
      stmt.execute();
      stmt.close();
   }

   public List<Contato> getLista() throws SQLException {

      PreparedStatement stmt = this.connection.prepareStatement("select * from contatos");
      ResultSet rs = stmt.executeQuery();

      List<Contato> list = new ArrayList<Contato>();
      while (rs.next()) {
         // criando o objeto Contato
         Contato contato = new Contato();
         contato.setId(rs.getLong("id"));
         contato.setNome(rs.getString("nome"));
         contato.setEmail(rs.getString("email"));
         contato.setEndereco(rs.getString("endereco"));

         // adicionando o objeto � lista
         list.add(contato);
      }

      rs.close();
      stmt.close();

      return list;
   }

   public void altera(Contato contato) throws SQLException {
      PreparedStatement stmt = connection.prepareStatement("update contatos set nome=?, email=?, endereco=? where id=?");
      stmt.setString(1, contato.getNome());
      stmt.setString(2, contato.getEmail());
      stmt.setString(3, contato.getEndereco());
      stmt.setLong(4, contato.getId());
      stmt.execute();
      stmt.close();
   }

   public void remove(Contato contato) throws SQLException {
      PreparedStatement stmt = connection.prepareStatement("delete from contatos where id=?");
      stmt.setLong(1, contato.getId());
      stmt.execute();
      stmt.close();
   }

   public Contato procura(Long id) throws SQLException {
      PreparedStatement stmt = connection.prepareStatement("select * from contatos where id=?");
      stmt.setLong(1, id);
      ResultSet rs = stmt.executeQuery();
      
      if(!rs.next()) return null;

      Contato c = new Contato();
      c.setId(rs.getLong("id"));
      c.setNome(rs.getString("nome"));
      c.setEmail(rs.getString("email"));
      c.setEndereco(rs.getString("endereco"));
      rs.close();
      stmt.close();
      return c;
   }
}

package br.com.ricardo.jdbc.jdbc;

import java.sql.*;
import javax.swing.*;

public class ConnectionFactory {

   public static Connection getConnection() throws SQLException {
      try {
      Class.forName("com.mysql.jdbc.Driver");
      JOptionPane.showMessageDialog(null, "Conectando ao banco", "Informação", 2);
      return DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/teste",   "root", "catia");
      } catch (ClassNotFoundException e) {
      throw new SQLException(e.getMessage());
      }
      }
}

// prepared statement para inser��o
       PreparedStatement stmt = this.connection.prepareStatement("insert into contatos (nome,email,endereco) values (?, ?, ?)");
 
       // seta os valores
       stmt.setString(1, contato.getNome());
       stmt.setString(2, contato.getEmail());
       stmt.setString(3, contato.getEndereco());