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java Hibernate:使用executeUpdate()的批删除未清除一级缓存

我的意图是使用executeUpdate()执行单个删除,而不是通过session.delete()循环,这是一种难以置信的聊天方式

我面临的问题是,通过执行executeUpdate(),它不会从一级缓存中逐出现有的已删除实体

下面是一个非常简单的示例:-

final Session session = sessionFactory.getCurrentSession();

System.out.println("---------------------------------");
System.out.println("What's currently in 1st level cache");
System.out.println("---------------------------------");

for (Object o : session.getStatistics().getEntityKeys()) {
    EntityKey entityKey = (EntityKey) o;
    System.out.println(entityKey.getEntityName() + " -> " + entityKey.getIdentifier());
}

System.out.println("---------------------------------");
System.out.println("Ensure there are 3 project users");
System.out.println("---------------------------------");

checkArgument(session.createQuery("from ProjectUser").list().size() == 3);

System.out.println("---------------------------------");
System.out.println("Deleting all 3 project users");
System.out.println("---------------------------------");

checkArgument(session.createQuery("delete from ProjectUser").executeUpdate() == 3);

session.flush();

System.out.println("---------------------------------");
System.out.println("Latest state in 1st level cache");
System.out.println("---------------------------------");

for (Object o : session.getStatistics().getEntityKeys()) {
    EntityKey entityKey = (EntityKey) o;
    System.out.println(entityKey.getEntityName() + " -> " + entityKey.getIdentifier());
}

这是我看到的打印件:-

---------------------------------
What's currently in 1st level cache
---------------------------------
testHibernate.domain.ProjectUser -> 2
testHibernate.domain.ProjectUser -> 1
testHibernate.domain.User -> 1
testHibernate.domain.ProjectUser -> 3
testHibernate.domain.User -> 3
testHibernate.domain.Project -> 1
testHibernate.domain.User -> 2
---------------------------------
Ensure there are 3 project users
---------------------------------
Hibernate: 
    select
        projectuse0_.projectUserId as projectU1_1_,
        projectuse0_.datetime as datetime2_1_,
        projectuse0_.projectId as projectI3_1_,
        projectuse0_.userId as userId4_1_ 
    from
        projectUser projectuse0_
[TRACE] [BasicExtractor] [extract:74] - Found [1] as column [projectU1_1_]
[TRACE] [BasicExtractor] [extract:74] - Found [2] as column [projectU1_1_]
[TRACE] [BasicExtractor] [extract:74] - Found [3] as column [projectU1_1_]
---------------------------------
Deleting all 3 project users
---------------------------------
Hibernate: 
    delete 
    from
        projectUser
---------------------------------
Latest state in 1st level cache
---------------------------------
testHibernate.domain.ProjectUser -> 2
testHibernate.domain.ProjectUser -> 1
testHibernate.domain.User -> 1
testHibernate.domain.ProjectUser -> 3
testHibernate.domain.User -> 3
testHibernate.domain.Project -> 1
testHibernate.domain.User -> 2

正如您所看到的,testHibernate.domain.ProjectUser实体仍然在一级缓存中徘徊,即使它们已经被删除

我的问题是如何使用executeUpdate()方法从一级缓存中清除已删除的实体?是否有任何官方文件解释这个问题

多谢各位


共 (1) 个答案

  1. # 1 楼答案

    这是我的解决方案,但它真的不整洁

    BaseEntity只是我们所有实体的基类

    @PersistenceContext
    transient EntityManager entityManager;
    
    @SuppressWarnings("unchecked")
    public void evict(Class<? extends BaseEntity> c)
    {
        HibernateEntityManager hem = entityManager.unwrap(HibernateEntityManager.class);
    
        Session session = hem.getSession();
    
        Query query = session.createQuery("select o from " + c.getSimpleName() + " o where isObsolete = false AND isDeleted = false");
    
        List<? extends BaseEntity> entities = (List<? extends BaseEntity>) query.list();
    
        for (BaseEntity e : entities)
        {
            session.evict(e);
        }
    }