我有一个名为具有父类别字段的类别的表。我正在使用该字段来获取子类别。我已经检查了类似问题的答案,建议是(fetch = FetchType.EAGER)。但我想加载它为LAZY,因为它是循环依赖。 (再次指向同一张表)。org.hibernate.LazyInitializationException:未能长期初始化角色集合
@Entity
@Table(name = "CATEGORY")
public class Category implements Serializable {
@Id
@Column(name = "ID")
@GeneratedValue
private Integer id;
@Column(name = "CATEGORY_NAME", nullable = false, length = 40)
private String name;
@Column(name = "DESCRIPTION", nullable = false, length = 255)
private String description;
@Column(name = "DATE_CREATED", nullable = false)
private Date dateCreated;
@Column(name = "UUID", nullable = false, length = 40)
private String uuid;
@ManyToOne
@JoinColumn(name = "PARENT_CATEGORY_ID")
private Category parentCategory;
@OneToMany(mappedBy = "parentCategory")
private Collection<Category> subCategories = new LinkedHashSet<Category>();
}
的错误是:
org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: com.hemanths.expense.manager.api.hibernate.entity.Category.subCategories, could not initialize proxy - no Session
at org.hibernate.collection.internal.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:566)
at org.hibernate.collection.internal.AbstractPersistentCollection.withTemporarySessionIfNeeded(AbstractPersistentCollection.java:186)
at org.hibernate.collection.internal.AbstractPersistentCollection.initialize(AbstractPersistentCollection.java:545)
at org.hibernate.collection.internal.AbstractPersistentCollection.read(AbstractPersistentCollection.java:124)
at org.hibernate.collection.internal.PersistentBag.iterator(PersistentBag.java:266)
有人可以帮助我找到解决办法?
感谢您的回复。 如果我说Hibernate.initialize(category.getSubCategories());它不会延迟加载。 而且因为它是相互依赖性,parentCategory将有subCategories,每个子类别将再次拥有parentCategory。它继续无限。 – 2015-03-03 16:48:21
对不起,这是现在发生了什么? – fujy 2015-03-03 18:10:12
是的。这就是为什么我想加载** lazily **。 – 2015-03-04 02:14:41