Error org.hibernate.LazyInitializationException

Question

Error org.hibernate.LazyInitializationException

Navigation

#1 by (1 votes)
#2 by (0 votes)

0

Error when the class handling is filled with the data in the database, if there is no record, I can access my xhtml normally. In the class account I correct with fetch = FetchType.EAGER, but in the class handling this error persists, See the relationships:

Account

@Entity
//@Cacheable
//@Table(uniqueConstraints={@UniqueConstraint(columnNames = { "agencia","numero" })})
public class Conta implements Serializable {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;

private String titular;
private String agencia;
private String numero;
private String banco;

@OneToOne
@JoinColumn(unique=true)
private Gerente gerente;

//@Cache(usage=CacheConcurrencyStrategy.TRANSACTIONAL)
@OneToMany(fetch = FetchType.EAGER, mappedBy="conta") 
private List<Movimentacao> movimentacoes;

getters e setters

Move

@Entity
public class Movimentacao implements Serializable {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;

private String descricao;
private Calendar data;
private BigDecimal valor;

@ManyToOne
private Conta conta;

@ManyToMany
@JoinTable(name = "categorias_da_movimentacao",
        joinColumns = @JoinColumn(name="movimentacao_id"))
private List<Categoria> categorias = new ArrayList<Categoria>();

@Enumerated(EnumType.STRING)
@Column(name = "tipo_movimentacao")
private TipoMovimentacao tipoMovimentacao;

getters e setters

Category

@Entity
public class Categoria implements Serializable {

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;

private String nome;

getters e setters

Error:

16:44:04,872 GRAVE [javax.enterprise.resource.webcontainer.jsf.application] (http-localhost-127.0.0.1-8080-1) Error Rendering View[/movimentacoes.xhtml]: 
javax.el.ELException: /movimentacoes.xhtml: failed to lazily initialize a collection of role: br.com.caelum.financas.modelo.Movimentacao.categorias, no session or session was closed
at com.sun.faces.facelets.compiler.TextInstruction.write(TextInstruction.java:90) [jsf-impl-2.1.7-jbossorg-2.jar:]

...

Caused by: org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: br.com.caelum.financas.modelo.Movimentacao.categorias, 
no session or session was closed
at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:393) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]

...

16:44:04,924 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/fj25-financas-web].[Faces Servlet]] (http-localhost-127.0.0.1-8080-1) Servlet.service() for servlet Faces Servlet threw exception: org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: br.com.caelum.financas.modelo.Movimentacao.categorias, no session or session was closed

...

jsf hibernate ejb

asked by anonymous 03.12.2015 / 20:06

2 answers

1

This error occurs because your list of categories is Lazy, you need to initialize your list first before performing an operation.

You will need to create a init() method in your Movimentacao class. Here's the logic to follow:

 start Transaction 
      Hibernate.initialize(getCategorias());
 end Transaction

Here are some examples in SOen:

How to load lazy fetched items from Hibernate / JPA in my controller

Hibernate: best practice to pull all lazy collections

03.12.2015 / 20:19

Instantiation error for class Menu wrap with icon and text aligned

score 0 · Accepted Answer

I've managed to solve this by changing my query in dao, where JPQL offers an explicit way to load relationships through join together with the fetch clause.

public List<Movimentacao> listaComCategorias() {
    return this.manager.createQuery("select distinct m from Movimentacao m left join fetch m.categorias",
            Movimentacao.class).getResultList();
}