Hibernate子查询上的ClassCastException

下面的代码有问题。类id是长的，B类id是嵌入的id，其中一个字段是类

DetachedCriteria dc = DetachedCriteria.forClass(A.class,"a").setProjection(Property.forName("a.id"));      
Criteria cr= this.sessionFactory.getCurrentSession().createCriteria(B.class,"b").add(Subqueries.in("b.id.a.id", dc));           
List<B> bb = cr.list();

但这是：

List<Long> dd =  this.sessionFactory.getCurrentSession().createCriteria(A.class,"a").setProjection(Property.forName("a.id")).list();
Criteria cr= this.sessionFactory.getCurrentSession().createCriteria(B.class,"b").add(Restrictions.in("b.id.a.id", dd));


List<B> bb = cr.list();

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工作。我做错了什么？

在这种情况下应该使用subquerys.propertyIn

List<Long> dd =  this.sessionFactory.getCurrentSession().createCriteria(A.class,"a").setProjection(Property.forName("a.id")).list();
Criteria cr= this.sessionFactory.getCurrentSession().createCriteria(B.class,"b").add(Restrictions.in("b.id.a.id", dd));


List<B> bb = cr.list();