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public class ClienteDAO {
	
	private Session session;
	public ClienteDAO(){
	}
	public void salvar(Cliente cli){
		session = HibernateUtil.getSessionFactory().getCurrentSession();
		session.beginTransaction();
		session.save(cli);
		session.getTransaction().commit();
	}
	
	public List listar(){
		session = HibernateUtil.getSessionFactory().openSession();
		session.beginTransaction();
		List l1 = session.createQuery("from Cliente").list();
		session.getTransaction().commit();
		return l1;
	}

}

List l1 = session.createQuery("from Cliente").list();

public class Principal {
	
	public static void main(String[] args) {
		Cliente c1 = new Cliente();
		c1.setNome(" ");
		c1.setIdade(new Long(20));
		
		Cliente c2 = new Cliente();
		c2.setNome(" ");
		c2.setIdade(new Long(21));
	
		ClienteDAO clienteDAO = new ClienteDAO();
		clienteDAO.salvar(c1);
		clienteDAO.salvar(c2);
		
		List<Cliente> listaClientes = clienteDAO.listar();
		for (Cliente cliente : listaClientes) {
		System.out.println(cliente.getId()+" - "+cliente.getNome());
		}
				
	}
	
	

}

List<Cliente> listaClientes = clienteDAO.listar();