Problems (Vraptor + Hibernate request)

Question

I’m using the Vraptor to develop a web application. More in certain tests, I saw that the Hibernate is adding in the database, but when I send the Result to my page with a new list of that object I deleted from my client, apparently he’s bringing something from the cache. At the base my client is with 3 items and the Hibernate brings only the old 2.

I put Dao as @RequestScoped, just to not have problems of this kind. How do I solve this problem?

Dao code:

public class DaoMaster {
private EntityManager manager;

@Inject
public DaoMaster(EntityManager manager) {
    this.manager = manager;
}

public DaoMaster() {
}

public void cria(Object o){
    manager.getTransaction().begin();
    manager.persist(o);
    manager.getTransaction().commit();
}

public void atualiza(Object o){
    manager.getTransaction().begin();
    manager.merge(o);
    manager.getTransaction().commit();

}

public void remove(Long id, Class<?> classe){
    Object o = buscaPorId(id, classe);
    manager.getTransaction().begin();
    manager.remove(o);
    manager.getTransaction().commit();
}

public Object buscaPorId(Long id,Class<?> classe){
    try{
        return manager.find(classe, id);
    }catch(Exception e){
        return null;
    }
}

public List<?> listaTodos(Class<?> classe){
    try{
        return manager.createQuery("select t from "+ classe.getSimpleName() +" t",classe).getResultList();
    }catch(Exception e){
        System.out.println("ERRO: "+e);
        return null;
    }
}

public List<?> listaPorQueryModificada(String queryModificada, HashMap<String, Object> parametros, Class<?> classe){
    try{
        TypedQuery<?> query = manager.createQuery(queryModificada,classe);
        if(parametros != null && parametros.size() > 0){
            for(String key: parametros.keySet()){
                Object value = parametros.get(key);
                query.setParameter(key, value);
            }
        }
        return query.getResultList();
    }catch(Exception e){
        System.out.println("ERRO: "+e);
        return null;
    }
}

public List<?> listaPorNamedQuery(String namedQuery, HashMap<String, Object> parametros,Class<?> classe){
    try{
        TypedQuery<?> query = manager.createNamedQuery(namedQuery,classe);
        if(parametros != null && parametros.size() > 0){
            for(String key: parametros.keySet()){
                Object value = parametros.get(key);
                query.setParameter(key, value);
            }
        }
        return query.getResultList();
    }catch(Exception e){
        System.out.println("ERRO: "+e);
        return null;
    }
}

public Object buscaPorNamedQuery(String namedQuery,HashMap<String, Object> parametros,Class<?> classe){
    Object objeto;
    try{
        TypedQuery<?> query = manager.createNamedQuery(namedQuery,classe);
        if(parametros != null && parametros.size() > 0){
            for(String key: parametros.keySet()){
                Object value = parametros.get(key);
                query.setParameter(key, value);
            }
        }
        return query.getSingleResult();
    }catch(Exception e){
        System.out.println("ERRO: "+e);
        return null;
    }
}

}

--Detailing--

I have a screen that I register subcategories, when registering a new item, I call a function with Vraptor to add, and at the end I have it redirected to my other function that makes the screen call. In the screen call function, I list all subcategories with Hibernate and send to the result, to be able to show on the user screen.

Only there is a time when I register a new item, the application registers this item at the base, and when it goes to the function of calling the screen again to do the new search of all existing subcategories, it seems that Hibernate is bringing the old research of the previous call, where there was not yet that new item that I just registered, making the new item does not exist on the screen.

Call code for Vraptor:

@Admin
public void listaSubCategoria(Long categoriaID){

    List<SubCategoria> subCategorias = subCategoriaDao.listaPorCategoria(categoriaID);
    result.include("categoria",categoriaDao.buscaPorId(categoriaID));
    result.include("subCategorias", subCategorias);
    result.include("pagina", "categoria");
}

@Admin
public void adicionaSubCategoria(SubCategoria subCategoria, UploadedFile imagem){
    /*VERIFICAR SE JÁ EXISTE UMA SUB CATEGORIA COM O MESMO NOME PARA NÃO DAR ERRO*/
    //subCategoriaDao.adiciona(subCategoria,imagem);
    if(subCategoria.getId() != null){
        daoMaster.atualiza(subCategoria);
    }else{
        subCategoria.setCategoria((Categoria) daoMaster.buscaPorId(subCategoria.getCategoria().getId(), Categoria.class));
        daoMaster.cria(subCategoria);
    }

    adicionaImagem(NomenclaturaArquivo._NOMENCLATURA_IMAGEM_CATEGORIA, imagem, subCategoria.getId());

    result.redirectTo(this).listaSubCategoria(subCategoria.getCategoria().getId());
}

Answer 1

Analyzing your code I saw that you are not giving commit in their consultations. The commit basically terminates the transaction by saving all changes that occurred during the transaction.

It is recommended to use commit in all transactions involving bank, even in consultations. It would look like this:

public Object buscaPorId(Long id,Class<?> classe){
    try{
        manager.getTransaction().begin();
        return manager.find(classe, id);
        manager.getTransaction().commit();
    }catch(Exception e){
        return null;
    }
}