我在我的应用程序中使用了一种“会话每会话”模式实现。在这种方法中，“NHibernate Session”保持在“HTTP Session”上。在每个“Http Request”中，“NHibernate Session”在开始时重新连接并在请求结束时断开连接。在“对话”结束时，“NHibernate Session”保存在“HTTP Session”中。这工作得很好。
问题：
现在我正在考虑在“Http Session”上使用“StateServer 模式”。因此，“HTTP Session”中的所有对象都必须是可序列化的，包括“NHibernate Session”。
所以我正在做一个概念证明来验证“NHibernate Session”及其缓存对象的序列化/反序列化是否有效。
“概念证明”是以下单元测试。目标是让它通过。
代码：
/*069*/ [Test]
/*070*/ public void Test()
/*071*/ {
/*072*/ //for inspecting the SQL commands
/*073*/ NhSqlLogCapture hhSqlLogCapture = new NhSqlLogCapture();
/*074*/
/*075*/ MemoryStream ms = new MemoryStream();
/*076*/
/*077*/ ISession sessionBefore = null;
/*078*/ ISession sessionAfter = null;
/*079*/
/*080*/ //querying before the serialization.
/*081*/ try
/*082*/ {
/*083*/ sessionBefore = this.sessionFactory.OpenSession();
/*084*/ sessionBefore.FlushMode = FlushMode.Auto;
/*085*/
/*086*/ hhSqlLogCapture.Enable();
/*087*/
/*088*/ //Querying only 'DetailEtt'
/*089*/ hhSqlLogCapture.SqlStatments.Clear();
/*090*/ ICriteria crt = sessionBefore.CreateCriteria<DetailEtt>();
/*091*/ crt
/*092*/ .SetFetchMode("Master", FetchMode.Select);
/*093*/ IList<DetailEtt> cen1DetailList = crt.List<DetailEtt>();
/*094*/
/*095*/ //BEGIN: Serializing
/*096*/ //also serializing an instance of 'DetailEtt' to verify that keeps only one instance to the same database record.
/*097*/ sessionBefore.Disconnect();
/*098*/ Object[] serializationArray = new object[] { sessionBefore, sessionBefore.Get<DetailEtt>(1) };
/*099*/ BinaryFormatter bf = new BinaryFormatter();
/*100*/ bf.Serialize(ms, serializationArray);
/*101*/ //END: Serializing
/*102*/
/*103*/ //assertions
/*104*/ //Checking the sql command executed.
/*105*/ Assert.AreEqual(1, hhSqlLogCapture.SqlStatments.Count, "hhSqlLogCapture.SqlStatments.Count");
/*106*/ Regex rx = new Regex("(?is).*SELECT.*FROM.*DETAIL.*");
/*107*/ Assert.IsTrue(rx.IsMatch(hhSqlLogCapture.SqlStatments[0]), hhSqlLogCapture.SqlStatments[0]);
/*108*/
/*109*/ hhSqlLogCapture.Disable();
/*110*/ }
/*111*/ finally
/*112*/ {
/*113*/ sessionBefore = null;
/*114*/ }
/*115*/
/*116*/ try
/*117*/ {
/*118*/ //BEGIN: Deserializing
/*119*/ BinaryFormatter bf = new BinaryFormatter();
/*120*/ ms.Seek(0, SeekOrigin.Begin);
/*121*/ Object[] deserializationArray = (Object[])bf.Deserialize(ms);
/*122*/ DetailEtt dtEttDeserialized = (DetailEtt)deserializationArray[1];
/*123*/ sessionAfter = (ISession)deserializationArray[0];
/*124*/ //BEGIN: Deserializing
/*125*/
/*126*/ IDbConnection conn = this.dbProvider.CreateConnection();
/*127*/ conn.Open();
/*128*/ sessionAfter.Reconnect(conn);
/*129*/
/*130*/ //Enabling again because the session loses the reference to the log (I think).
/*131*/ hhSqlLogCapture.Enable();
/*132*/ hhSqlLogCapture.SqlStatments.Clear();
/*133*/
/*134*/ DetailEtt dtEtdSSGet = sessionAfter.Get<DetailEtt>(1);
/*135*/ MasterEtt mtEtd = dtEtdSSGet.Master;
/*136*/ Console.WriteLine(mtEtd.Description);
/*137*/
/*138*/ //assertions
/*139*/ //Checking the sql command executed.
/*140*/ Assert.AreEqual(1, hhSqlLogCapture.SqlStatments.Count, "hhSqlLogCapture.SqlStatments.Count");
/*141*/ Regex rx = new Regex("(?is).*SELECT.*FROM.*MASTER.*");
/*142*/ Assert.IsTrue(rx.IsMatch(hhSqlLogCapture.SqlStatments[0]), hhSqlLogCapture.SqlStatments[0]);
/*143*/ //verify that keeps only one instance to the same database record
/*144*/ Assert.AreSame(dtEttDeserialized, dtEtdSSGet, "verify that keeps only one instance to the same database record");
/*145*/ }
/*146*/ finally
/*147*/ {
/*148*/ sessionAfter.Close();
/*149*/ }
/*150*/ }
测试通过了几乎所有内容。但是当尝试加载“懒惰”的实体时它会失败。
错误：
SofPOC.Questions.SerializeSession.SerializeSessionTest.Test:
NHibernate.LazyInitializationException : Initializing[SofPOC.Questions.SerializeSession.Entities.MasterEtt#5]-Could not initialize proxy - no Session. em NHibernate.Proxy.AbstractLazyInitializer.Initialize()
at NHibernate.Proxy.AbstractLazyInitializer.Initialize()
at Spring.Data.NHibernate.Bytecode.LazyInitializer.Invoke(IMethodInvocation invocation) in c:\_prj\spring-net\trunk\src\Spring\Spring.Data.NHibernate21\Data\NHibernate\Bytecode\LazyInitializer.cs:line 101
at Spring.Aop.Framework.AbstractMethodInvocation.Proceed() in c:\_prj\spring-net\trunk\src\Spring\Spring.Aop\Aop\Framework\AbstractMethodInvocation.cs:line 284
at Spring.Aop.Framework.DynamicProxy.AdvisedProxy.Invoke(Object proxy, Object target, Type targetType, MethodInfo targetMethod, MethodInfo proxyMethod, Object[] args, IList interceptors) in c:\_prj\spring-net\trunk\src\Spring\Spring.Aop\Aop\Framework\DynamicProxy\AdvisedProxy.cs:line 208
at DecoratorAopProxy_9872659265c04d36bc9738f2aaddfb08.get_Description()
at SofPOC.Questions.SerializeSession.SerializeSessionTest.Test() in C:\Users\hailtondecastro\lixo\stackoverflow\dotnet\StackoverflowNetPOCs_20120718\src\SofPOC.Net4.NH2.Spring13.2010\Questions\SerializeSession\SerializeSessionTest.cs:line 136
详细信息：
[Serializable]
public class DetailEtt
{
private Int32? id;
/// <summary>
/// PK
/// </summary>
public virtual Int32? Id
{
get { return id; }
set { id = value; }
}
private String description;
/// <summary>
/// TODO:
/// </summary>
public virtual String Description
{
get { return description; }
set { description = value; }
}
private MasterEtt master;
/// <summary>
/// TODO:
/// </summary>
public virtual MasterEtt Master
{
get { return master; }
set { master = value; }
}
}
马斯特埃特：
[Serializable]
public class MasterEtt
{
private Int32? id;
/// <summary>
/// PK
/// </summary>
public virtual Int32? Id
{
get { return id; }
set { id = value; }
}
private String description;
/// <summary>
/// TODO:
/// </summary>
public virtual String Description
{
get { return description; }
set { description = value; }
}
}
DetailEtt.hbm.xml：
<?xml version="1.0" encoding="utf-8"?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="SofPOC.Questions.SerializeSession.Entities" assembly="SofPOC.Net4.NH2.Spring13">
<class name="DetailEtt" table="DETAIL">
<id name="Id" type="Int32">
<column name="ID" sql-type="INTEGER"></column>
<generator class="assigned"></generator>
</id>
<property name="Description" type="String">
<column name="DESCRIPTION" sql-type="VARCHAR( 100 )"></column>
</property>
<many-to-one name="Master" fetch="select">
<column name="MS_ID" sql-type="INTEGER"></column>
</many-to-one>
</class>
</hibernate-mapping>
MasterEtt.hbm.xml：
<?xml version="1.0" encoding="utf-8"?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="SofPOC.Questions.SerializeSession.Entities" assembly="SofPOC.Net4.NH2.Spring13">
<class name="MasterEtt" table="MASTER">
<id name="Id" type="Int32">
<column name="ID" sql-type="INTEGER"></column>
<generator class="assigned"></generator>
</id>
<property name="Description" type="String">
<column name="DESCRIPTION" sql-type="VARCHAR( 100 )"></column>
</property>
</class>
</hibernate-mapping>
问题：
即使重新连接反序列化的“休眠会话”，我也会收到“延迟加载错误”。如何避免这种“延迟加载错误”而无需重新附加实体？
我正在使用：
- Spring.Net 1.3.2
- NHibernate 2.1.2
- System.Data.SQLite 1.0.80.0
完整的源代码在这里：Q11553780.7z
笔记：
- 在打开解决方案（“.\Src\SofPOC.2010.sln”）之前，运行“.\Dependencies\setup.bat”来加载依赖项。
- 有关依赖项的说明，请参阅“.\readme.txt”和“.\dependencies\readme.txt”。
编辑：
我发现问题的原因是在NHibernate.Proxy.AbstractLazyInitializerNHibernate 的类中。该字段_session标记为[NonSerialized]。这使得该字段不被序列化。因此它在反序列化后为空。
见代码：
namespace NHibernate.Proxy
{
[Serializable]
public abstract class AbstractLazyInitializer : ILazyInitializer
{
/// <summary>
/// If this is returned by Invoke then the subclass needs to Invoke the
/// method call against the object that is being proxied.
/// </summary>
protected static readonly object InvokeImplementation = new object();
private object _target = null;
private bool initialized;
private object _id;
[NonSerialized]
private ISessionImplementor _session;
...
编辑2：
问题的原因实际上是属性 [NonSerialized] 因为当我进行以下“破解”时，测试通过了。通过反射，我将“_session”的属性从“Private | NotSerialized”更改为“Private”。
黑客：
protected override void OnSetUp()
{
//Hacking "_session"
Type aliType = Type.GetType("NHibernate.Proxy.AbstractLazyInitializer, NHibernate");
FieldInfo fiSession = aliType.GetField("_session", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);
FieldInfo fi_m_fieldAttributes =
fiSession.GetType().GetField(
"m_fieldAttributes",
System.Reflection.BindingFlags.NonPublic
| System.Reflection.BindingFlags.Instance);
// changing it from "Private | NotSerialized" to only "Private"
fi_m_fieldAttributes.SetValue(fiSession, FieldAttributes.Private);
base.OnSetUp();
}