private void insertData() {
   for (int i = 0; i < 3; i++) {
     ProductoEntity entity = new ProductoEntity();
     entity.setName(generateRandom(String.class));
     entity.setCosto(generateRandom(Integer.class));
     entity.setPeso(generateRandom(Integer.class));
     em.persist(entity);
     data.add(entity);
   }
 }