Ajuda com conexao JAVA->DERBY por favoooor

`/*

• To change this license header, choose License Headers in Project Properties.
• To change this template file, choose Tools | Templates
• and open the template in the editor.
  */
  package com.giovanni.clinica.model.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

import javax.swing.JOptionPane;

/**
*

• @author root
  */
  public class ConexaoDb implements ConexaoInterface {

  private String usuario;
  
  private String senha;
  
  private String hostname;
  
  private int porta;
  
  private String nomebanco;
  
  private Connection conexao;
  

  public ConexaoDb(String usuario, String senha, String hostname, int porta, String nomebanco) {
  
  this.usuario = usuario;
  
  this.senha = senha;
  
  this.hostname = hostname;
  
  this.porta = porta;
  
  this.nomebanco = nomebanco;
  
  }
  

  <a class="mention" href="/u/override">@Override</a>
  
  public Connection getConnection() {
  
  if (conexao == null) {
  
  try {
  
  Class.forName(“org.apache.derby.jdbc.ClientDriver”);
  
  String url = “jdbc:derby://” + hostname + “:” + porta + “/” + nomebanco;
  
  conexao = DriverManager.getConnection(url);
  
  } catch (ClassNotFoundException ex) {
  
  JOptionPane.showMessageDialog(null, "Classe db:derby não encontrada "+ex);
  
  } catch (SQLException ex) {
  
  JOptionPane.showMessageDialog(null, “DriverManeger exception”);
  
  }
  
  }
  
  return conexao;
  
  }
  

  <a class="mention" href="/u/override">@Override</a>
  
  public void close() {
  
  try {
  
  conexao.close();
  
  } catch (SQLException ex) {
  
  }
  
  }
  

}

`
Ele exibe na tela “classe db:derby nao encontrada”… tipo nao sei mais o que fazer alguem tem ideia do que pode ser?