休眠提取多个关联 [英] Hibernate fetch with multiple associations
本文介绍了休眠提取多个关联的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
@Transactional(readOnly = true)
public T getWithAssociation(final long id,String association){
Session session = sessionFactory.getCurrentSession();
final Criteria crit = session.createCriteria(genericType);
crit.setFetchMode(association,FetchMode.JOIN);
crit.add(Property.forName(id)。eq(id));
return(T)crit.uniqueResult();
}
我想返回一个带有多个延迟加载集合的实体对象,我可以这样做吗(传入一个列表并设置多于单个标准的关联?):
@Transactional(readOnly = true)
public T getWithAssociations(final long id,List< String>关联){
Session session = sessionFactory.getCurrentSession();
final Criteria crit = session.createCriteria(genericType);
for(String association:associations){
crit.setFetchMode(association,FetchMode.JOIN);
}
crit.add(Property.forName(id)。eq(id));
return(T)crit.uniqueResult();
解决方案
是吗?
docs 包含以下内容:
列表cats = sess.createCriteria(Cat.class)
.add(Fritz%))
.setFetchMode(mate,FetchMode.EAGER)
.setFetchMode(kittens,FetchMode.EAGER)
.list();
这个查询将通过外连接获取配偶和小猫。有关更多信息,请参见第20.1节获取策略。
I am doing this for my lazy load collections on entity objects :
@Transactional(readOnly = true)
public T getWithAssociation(final long id, String association) {
Session session = sessionFactory.getCurrentSession();
final Criteria crit = session.createCriteria(genericType);
crit.setFetchMode(association, FetchMode.JOIN);
crit.add(Property.forName("id").eq(id));
return (T) crit.uniqueResult();
}
I want to return an entity object with multiple lazy loaded collections loaded, can I do this (pass in a list and set more than association for a single criteria?) :
@Transactional(readOnly = true)
public T getWithAssociations(final long id, List<String> associations) {
Session session = sessionFactory.getCurrentSession();
final Criteria crit = session.createCriteria(genericType);
for(String association:associations) {
crit.setFetchMode(association, FetchMode.JOIN);
}
crit.add(Property.forName("id").eq(id));
return (T) crit.uniqueResult();
}
解决方案
Yes?
The docs contain the following:
List cats = sess.createCriteria(Cat.class)
.add( Restrictions.like("name", "Fritz%") )
.setFetchMode("mate", FetchMode.EAGER)
.setFetchMode("kittens", FetchMode.EAGER)
.list();
This query will fetch both mate and kittens by outer join. See Section 20.1, "Fetching strategies" for more information.
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