休眠ManyToOne与FetchType.LAZY不提取懒惰 [英] Hibernate ManyToOne with FetchType.LAZY not fetching lazy
问题描述
我在spring中使用Hibernate。
I am using Hibernate with spring.
我有这样的模型类。
I have a model-class like this.
@Entity
@Table(name = "forumtopic")
public final class Forumtopic extends AbstractUserTracking implements
java.io.Serializable {
/**SNIP **/
private Forumcategory forumcategory;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "FkForumcategoryId", nullable = false)
public Forumcategory getForumcategory() {
return this.forumcategory;
}
public void setForumcategory(final Forumcategory forumcategory) {
this.forumcategory = forumcategory;
}
}
一般情况下,类没有加载懒,但在ForumEntry已经加载之后急切地加载。
It works in general, but the Category is not loaded lazy, but eagerly after the ForumEntry has been loaded.
Hibernate:
select
forumtopic0_.PkId as PkId19_0_,
forumtopic0_.CreateDate as CreateDate19_0_,
forumtopic0_.FkCreateUserId as FkCreate3_19_0_,
forumtopic0_.FkLastUserId as FkLastUs4_19_0_,
forumtopic0_.LastChange as LastChange19_0_,
forumtopic0_.FkForumcategoryId as FkForum10_19_0_,
forumtopic0_.PublishCategory as PublishC6_19_0_,
forumtopic0_.State as State19_0_,
forumtopic0_.Text as Text19_0_,
forumtopic0_.Topic as Topic19_0_,
forumtopic0_.FkTpUserId as FkTpUserId19_0_
from
forumtopic forumtopic0_
where
forumtopic0_.PkId=?
Hibernate:
select
forumcateg0_.PkId as PkId17_0_,
forumcateg0_.CreateDate as CreateDate17_0_,
forumcateg0_.Name as Name17_0_,
forumcateg0_.FkRequestId as FkReques4_17_0_,
forumcateg0_.FkTpUserId as FkTpUserId17_0_
from
forumcategory forumcateg0_
where
forumcateg0_.PkId=?
尽管没有调用getter,ForumCategory会在ForumTopic之后加载。
Altough the getter was not called the ForumCategory is loaded right after ForumTopic.
这个问题出现在我的所有@ ManyToOne关联中。然而@OneToMany关联是懒惰地加载的。
This problems appears in all my @ManyToOne-associations. However @OneToMany associating are loaded lazily.
我正在使用maven2进行构建。这些是我的依赖。
I am using maven2 for the build. These are my dependencies.
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring</artifactId>
<version>2.5.6</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>3.3.1.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>ejb3-persistence</artifactId>
<version>1.0.2.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-annotations</artifactId>
<type>jar</type>
<version>3.4.0.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<type>jar</type>
<version>3.4.0.GA</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-search</artifactId>
<version>3.1.0.GA</version>
</dependency>
有人可以帮我理解发生了什么吗?
Can someone please help me understand what is happening?
推荐答案
我想这是由事实你的类声明为 final
,因此Hibernate不能为它们生成延迟代理。尝试从类声明中移除 final 。
I guess it's caused by the fact that your classes are declared as final
, therefore Hibernate cannot generate lazy proxies for them. Try to remove final
from class declarations.
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