After some more extensive debugging, I have managed to get a bit closer to the problem and have been able to create a small test case application that can reliably reproduce the problem. It looks like it might be a bug at this stage as I can't see anything that is wrong with the code in the mini-app.
All of the objects are sorted OK when they are first loaded from the DB but it goes awry after a postback triggers the rehydration of the objects from the 2nd level cache.
It looks like it takes a certain combination of relationships to cause the problem:
Parent object has 2 child collections (A & B)
Object in collection A references an object in collection B
Object in collection A loaded from the session after it has already been added to the 2nd level cache
If I load the parent from the session, then all the collections are loaded OK and the sorting works fine. If I load an object contained in collection A from the session, then the error occurs with the sorting.
Here is all the code from the mini-app that reproduces the problem (I have put stuff into single files wherever possible to make it easier to paste in here!). There is a domain assembly called MyDomain and a website called MyDomainUI that references MyDomain.
MyDomain - DomainObjects.cs:
Code:
using System;
using System.Collections;
using System.Text;
using Iesi.Collections;
namespace MyDomain
{
public class Parent
{
private int _id;
private string _name;
private ISet _children;
private ISet _differentChildren;
public virtual int ID
{
get
{
return this._id;
}
set
{
this._id = value;
}
}
public virtual string Name
{
get
{
return this._name;
}
set
{
this._name = value;
}
}
public virtual ISet Children
{
get
{
return this._children;
}
set
{
this._children = value;
}
}
public virtual ISet DifferentChildren
{
get
{
return this._differentChildren;
}
set
{
this._differentChildren = value;
}
}
public Parent()
{
this._children = new HashedSet();
this._differentChildren = new HashedSet();
}
}
public class Child
{
private int _id;
private string _name;
private Parent _parent;
private RelatedObject _relatedObject;
public virtual int ID
{
get
{
return this._id;
}
set
{
this._id = value;
}
}
public virtual string Name
{
get
{
return this._name;
}
set
{
this._name = value;
}
}
public virtual Parent Parent
{
get
{
return this._parent;
}
set
{
this._parent = value;
}
}
public virtual RelatedObject RelatedObject
{
get
{
return this._relatedObject;
}
set
{
this._relatedObject = value;
}
}
}
public class DifferentChild
{
private int _id;
private string _name;
private Parent _parent;
private Child _child;
public virtual int ID
{
get
{
return this._id;
}
set
{
this._id = value;
}
}
public virtual string Name
{
get
{
return this._name;
}
set
{
this._name = value;
}
}
public virtual Parent Parent
{
get
{
return this._parent;
}
set
{
this._parent = value;
}
}
public virtual Child Child
{
get
{
return this._child;
}
set
{
this._child = value;
}
}
}
public class RelatedObject
{
private int _id;
private string _name;
public virtual int ID
{
get
{
return this._id;
}
set
{
this._id = value;
}
}
public virtual string Name
{
get
{
return this._name;
}
set
{
this._name = value;
}
}
}
public class ChildComparer : IComparer
{
public int Compare(object x, object y)
{
return ((Child)x).RelatedObject.Name.CompareTo(((Child)y).RelatedObject.Name);
}
}
}
MyDomain - DomainObjects.hbm.xml:
Code:
<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0" schema="dbo">
<class name="MyDomain.Parent, MyDomain" table="Parent">
<cache usage="read-write"/>
<id name="ID" type="Int32" column="ID">
<generator class="identity"/>
</id>
<property name="Name" column="Name" type="String" length="200" not-null="true"/>
<set name="Children" table="Child" inverse="true" lazy="false" cascade="all-delete-orphan" sort="MyDomain.ChildComparer, MyDomain">
<cache usage="read-write"/>
<key column="ParentID"/>
<one-to-many class="MyDomain.Child, MyDomain"/>
</set>
<set name="DifferentChildren" table="DifferentChild" inverse="true" lazy="false" cascade="all-delete-orphan">
<cache usage="read-write"/>
<key column="ParentID"/>
<one-to-many class="MyDomain.DifferentChild, MyDomain"/>
</set>
</class>
<class name="MyDomain.Child, MyDomain" table="Child">
<cache usage="read-write"/>
<id name="ID" type="Int32" column="ID">
<generator class="identity"/>
</id>
<property name="Name" column="Name" type="String" length="200" not-null="true"/>
<many-to-one name="Parent" column="ParentID" class="MyDomain.Parent, MyDomain" not-null="true"/>
<many-to-one name="RelatedObject" column="RelatedObjectID" class="MyDomain.RelatedObject, MyDomain" not-null="true"/>
</class>
<class name="MyDomain.DifferentChild, MyDomain" table="DifferentChild">
<cache usage="read-write"/>
<id name="ID" type="Int32" column="ID">
<generator class="identity"/>
</id>
<property name="Name" column="Name" type="String" length="200" not-null="true"/>
<many-to-one name="Parent" column="ParentID" class="MyDomain.Parent, MyDomain" not-null="true"/>
<many-to-one name="Child" column="ChildID" class="MyDomain.Child, MyDomain" />
</class>
<class name="MyDomain.RelatedObject, MyDomain" table="RelatedObject">
<cache usage="read-write"/>
<id name="ID" type="Int32" column="ID">
<generator class="identity"/>
</id>
<property name="Name" column="Name" type="String" length="200" not-null="true"/>
</class>
</hibernate-mapping>
MyDomainUI - Global.asax:
Code:
<%@ Application Language="C#" %>
<script runat="server">
void Application_Start(object sender, EventArgs e)
{
NHibernate.Cfg.Configuration configuration = new NHibernate.Cfg.Configuration();
configuration.AddAssembly("MyDomain");
Application["SessionFactory"] = configuration.BuildSessionFactory();
}
void Application_End(object sender, EventArgs e)
{
// Code that runs on application shutdown
}
void Application_Error(object sender, EventArgs e)
{
// Code that runs when an unhandled error occurs
}
void Session_Start(object sender, EventArgs e)
{
// Code that runs when a new session is started
}
void Session_End(object sender, EventArgs e)
{
// Code that runs when a session ends.
// Note: The Session_End event is raised only when the sessionstate mode
// is set to InProc in the Web.config file. If session mode is set to StateServer
// or SQLServer, the event is not raised.
}
</script>
MyDomainUI - Default.aspx:
Code:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
Parent name: <asp:Label ID="_parentNameLabel" runat="server"></asp:Label>
<asp:GridView ID="_childGrid" runat="server" OnRowEditing="_childGrid_RowEditing" DataKeyNames="ID">
<Columns>
<asp:CommandField ShowEditButton="true" />
</Columns>
</asp:GridView>
</form>
</body>
</html>
MyDomainUI - Default.aspx.cs:
Code:
using System;
using System.Collections;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using NHibernate;
using MyDomain;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (this.IsPostBack == false)
{
this.Initialise();
}
}
private void Initialise()
{
ISession session = this.OpenSession();
Parent parent;
parent = (Parent)session.Get(typeof(Parent), 1);
this._parentNameLabel.Text = parent.Name;
this._childGrid.DataSource = parent.DifferentChildren;
this._childGrid.DataBind();
session.Close();
}
protected void _childGrid_RowEditing(object sender, GridViewEditEventArgs e)
{
ISession session = this.OpenSession();
int id = (int)this._childGrid.DataKeys[e.NewEditIndex].Value;
DifferentChild differentChild = (DifferentChild)session.Get(typeof(DifferentChild), id);
session.Close();
}
private ISession OpenSession()
{
ISessionFactory factory = (ISessionFactory)Application["SessionFactory"];
return factory.OpenSession();
}
}
MyDomainUI - Web.config:
Code:
<?xml version="1.0"?>
<!--
Note: As an alternative to hand editing this file you can use the
web admin tool to configure settings for your application. Use
the Website->Asp.Net Configuration option in Visual Studio.
A full list of settings and comments can be found in
machine.config.comments usually located in
\Windows\Microsoft.Net\Framework\v2.x\Config
-->
<configuration>
<configSections>
<section name="syscache" type="NHibernate.Caches.SysCache.SysCacheSectionHandler,NHibernate.Caches.SysCache"/>
<section name="nhibernate" type="System.Configuration.NameValueSectionHandler, System, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"/>
</configSections>
<nhibernate>
<add key="hibernate.connection.provider" value="NHibernate.Connection.DriverConnectionProvider"></add>
<add key="hibernate.connection.driver_class" value="NHibernate.Driver.SqlClientDriver"></add>
<add key="hibernate.connection.connection_string" value="Initial Catalog=MyDomain;Data Source=(local);User ID=sa;password=verbatim;"></add>
<add key="hibernate.connection.isolation" value="ReadCommitted"></add>
<add key="hibernate.default_schema" value="MyDomain.dbo"></add>
<add key="hibernate.show_sql" value="false"></add>
<add key="hibernate.dialect" value="NHibernate.Dialect.MsSql2000Dialect"></add>
<add key="hibernate.query.substitutions" value="true 1, false 0, yes 'Y', no 'N'"></add>
<add key="hibernate.hibernate.cache.provider_class" value="NHibernate.Caches.SysCache.SysCacheProvider, NHibernate.Caches.SysCache"></add>
<add key="hibernate.expiration" value="600"></add>
<add key="hibernate.cache.use_query_cache" value="true"></add>
</nhibernate>
<appSettings/>
<connectionStrings/>
<system.web>
<!--
Set compilation debug="true" to insert debugging
symbols into the compiled page. Because this
affects performance, set this value to true only
during development.
-->
<compilation debug="true"/>
<!--
The <authentication> section enables configuration
of the security authentication mode used by
ASP.NET to identify an incoming user.
-->
<authentication mode="Windows"/>
<!--
The <customErrors> section enables configuration
of what to do if/when an unhandled error occurs
during the execution of a request. Specifically,
it enables developers to configure html error pages
to be displayed in place of a error stack trace.
<customErrors mode="RemoteOnly" defaultRedirect="GenericErrorPage.htm">
<error statusCode="403" redirect="NoAccess.htm" />
<error statusCode="404" redirect="FileNotFound.htm" />
</customErrors>
-->
</system.web>
</configuration>
Login
FAQ
Search
