java – Hibernate：如何获取当前在会话中的所有对象的列表

我得到了好的,老旧的可怕的TransientObjectException,并且在这种情况下经常发生,我在找到什么样的微妙错误导致问题的时候遇到问题.

我的问题是：有没有办法获取当前Hibernate会话中的每个对象的列表？

当我得到这个问题的答案时,我可能已经解决了当前的问题,但无论如何,无论如何,能够列出会话的所有内容将在下一次发生的时候帮助很多.

解决方法

Hibernate并没有将其内部公开给公众,所以你不会在公共API中找到你要搜索的内容.但是,您可以在Hibernate接口的实现类中找到答案：
此方法(从 http://code.google.com/p/bo2/source/browse/trunk/Bo2ImplHibernate/main/gr/interamerican/bo2/impl/open/hibernate/HibernateBo2Utils.java 获取)将告诉会话中是否存在对象：

public static Object getFromSession
        (Serializable identifier,Class<?> clazz,Session s) {              
    String entityName = clazz.getName();
    if(identifier == null) {
       return null;
    }      
    SessionImplementor sessionImpl = (SessionImplementor) s;
    EntityPersister entityPersister = sessionImpl.getFactory().getEntityPersister(entityName);
    PersistenceContext persistenceContext = sessionImpl.getPersistenceContext();
    EntityKey entityKey = new EntityKey(identifier,entityPersister,EntityMode.POJO);
    Object entity = persistenceContext.getEntity(entityKey);
    return entity;
    }

如果你再深入一下,你会看到PersistenceContext的唯一实现是org.hibernate.engine.StatefulPersistenceContext.
这个类有以下集合：

// Loaded entity instances,by EntityKey
private Map entitiesByKey;

// Loaded entity instances,by EntityUniqueKey
private Map entitiesByUniqueKey;

// Identity map of EntityEntry instances,by the entity instance
private Map entityEntries;

// Entity proxies,by EntityKey
private Map proxiesByKey;

// Snapshots of current database state for entities
// that have *not* been loaded
private Map entitySnapshotsByKey;

// Identity map of array holder ArrayHolder instances,by the array instance
private Map arrayHolders;

// Identity map of CollectionEntry instances,by the collection wrapper
private Map collectionEntries;

// Collection wrappers,by the CollectionKey
private Map collectionsByKey; //key=CollectionKey,value=PersistentCollection

// Set of EntityKeys of deleted objects
private HashSet nullifiableEntityKeys;

// properties that we have tried to load,and not found in the database
private HashSet nullAssociations;

// A list of collection wrappers that were instantiating during result set
// processing,that we will need to initialize at the end of the query
private List nonlazyCollections;

// A container for collections we load up when the owning entity is not
// yet loaded ... for now,this is purely transient!
private Map unownedCollections;

// Parent entities cache by their child for cascading
// May be empty or not contains all relation 
private Map parentsByChild;

所以,你需要做的是将PersistenceContext转换为StatefulPersistenceContext,然后使用反射来获取所需的私有集合,然后对其进行迭代.

我强烈建议你只做调试代码.这不是公共API,它可能会被新的Hibernate版本制动.

原文链接：https://www.f2er.com/java/126936.html

java – Hibernate：如何获取当前在会话中的所有对象的列表

解决方法

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