ModSecurity is
a powerful module for Apache to monitor traffic and prevent attacks with a set of
rules based on urls, variables, SOAP parameter values etc… It can be deployed on
Apache 2.0 and 2.2. Some samples of http.conf file can be misleading if you use Apache
2.0 :

<IfModule security2_module>



     Include conf/rules/*.conf



</IfModule>

When you start Apache you will see a log entry about the successful configuration
of security2_module. But the module itself doesn’t log anything and your rules don’t
work. The appropriate module directive for Apache 2.0 is :

<IfModule security2_module.c>



     Include conf/rules/*.conf



</IfModule>

For Apache on Windows you can use the binaries from apachelounge.com

Most of the time we don’t care about the hibernate mapping configuration when we deploy
an application based on JBPM (a
worflow framework from Jboss). But if you want to use the same session factory for
JBPM and your custom objects (the JBPM
spring module have some helper classes) you have several options for the
sessionFactory bean declaration in the spring configuration file :

• use two mapping sections : one for the JBPM jar file and one for the directory where
  the mapping files of custom objects are :

            
              <
              bean 
              id="sessionFactory"...>

            <
            property 
            name="mappingDirectoryLocations"> <list> <value>classpath*:**/your/custom/objects/mapping</value> </list> </property> <property name="mappingJarLocations"> <list> <value>file:**/jbpm-jpdl.jar</value></list> </property> </bean>

• or extract the JBPM mapping files (find all .hbm.xml files in the extracted JAR) and
  add the directory to the mappingDirectoryLocations :
  
  

  <property name="mappingDirectoryLocations"> <list> <value>classpath*:**/your/custom/objects/mapping</value> <value>classpath:/the/directory/JBPM/mapping/files/</value> </list> </property>

  but the order of the mapping files is important : JBPM has a custom type (string_max)
  declared in the hibernate.queries.hbm.xml file, this file should be before any other
  JBPM mapping file. I not you encounter this exception when the session factory
  is build :

Caused by: org.hibernate.MappingException: Could not determine type for: string_max,
for columns: [org.hibernate.mapping.Column(MESSAGE_)]


or


Caused by: org.hibernate.MappingException: Could not determine type for: string_max,
for columns: [org.hibernate.mapping.Column(DESCRIPTION_)] …

And if you use the 3.2 version of JBPM with the spring module (for 3.1) one minor
modification is needed from the manual :  

• The transactionnal service in the jbpm.cfg.xml : <service name="tx" factory="org.jbpm.tx.TxServiceFactory"
  /> is mandatory

I just finished the first version of the "twitter viewer" in C# with WPF. I’ve some
layout modifications to be done but the application is ready.

Download the source (Visual Studio 2008 beta 2)

Download the application (unzip and launch the .exe file)

Some screenshots :

when the user clicks on an hyperlink : 

the settings page, username and password for the first version :

In my TwitterViewer in WPF I found that status can have urls in the body so they can’t
be bind directly to a TextBlock.
With a Converter I find maybe a good solution : Split the text with a regular expression,
build inline elements (simple Run for
text and Hyperlink for
urls) and put them in the Inlines property of the TextBlock :

<
Label
Margin
="8,0,8,0"
x
:
Name
="status"
Grid
.
Column
="1"
>


      <
Label
.
Content
>





<
Binding
Path
="Text"
Converter
="{StaticResource
urlConverter}"/>


       </
Label
.
Content
>


</
Label
>

And the code of the Converter implementation :

          String[] LinksText = Regex.Split((String)value, @"(\bhttp://[^
]+\b)"); TextBlock txtBlock = newTextBlock();
txtBlock.TextWrapping = System.Windows.TextWrapping.Wrap; foreach (String textSplit in LinksText)
{ if (textSplit.Length > 0) { if (textSplit.Substring(0,
1).Equals("h")) { Hyperlink textFormate
= newHyperlink(newRun(textSplit));
textFormate.NavigateUri = newUri(textSplit);
txtBlock.Inlines.Add(textFormate); } else  {
txtBlock.Inlines.Add(newRun(textSplit));
} } } return txtBlock;

I’ve read a lot of tutorials about databinding in WPF but often it’s all about XAML.
In my TwitterViewer
application in WPF I need to update the TwitterManager class with username
and password of the user. I choose to set the binding in code. Here is the constructor
of the main page :

          public MainPage() { InitializeComponent(); //create
a provider  odp = newObjectDataProvider();
odp.MethodName = "GetStatuses"; odp.ObjectInstance
= newTwitterManager("tewmgd", "xxxx");
odp.IsInitialLoadEnabled = false; Binding myBinding
= newBinding();
myBinding.Source = odp; //set the source of the
ItemsSource  statusList.SetBinding(ListView.ItemsSourceProperty,
myBinding); odp.Refresh(); }

With an  hyperLink the user can navigate to another page to change the settings
(username and password). The PageFunction control
allows the launching page to subscribe to the Return event and since it’s a generic
class, the return object is typesafe :

          void settingsLink_Click(object sender, RoutedEventArgs e)
{ //create a new instance of the settings page SettingsPage pageFunction
= newSettingsPage(); //subscribe
to the return event  pageFunction.Return += newReturnEventHandler<TwitterManager>

(OnSettingsReturned); this.NavigationService.Navigate(pageFunction);
}

          public
          void OnSettingsReturned(object sender,ReturnEventArgs<TwitterManager>
e) { //change the source of the provider  odp.ObjectInstance
= e.Result; //refresh the provider and with it the
listview  odp.Refresh(); }

In the target page the button event
handler uses the OnReturn method to navigate backward and set the result object :

          private
          void OnClickDone(object sender, RoutedEventArgs e)
{ OnReturn(newReturnEventArgs<TwitterManager>(
newTwitterManager(this.txtUserName.Text,this.txtPassword.Text)));
}

          Update, screenshoots of the two pages :
        

One of the hardest things in WPF it’s that there are many ways to reach the
same result. The same is true with other frameworks, but WPF and its language,
XAML, allow for some powerful and complex design with a large collection
of concepts : dependency properties , attached properties, control templates,
item templates, styles and so on… I’m currently writing a simple Twitter viewer
as a way to learn WPF. This "application" simply shows the xml-based feed of a user’s
friends through the API :

I created classes from the feed through the XSD schema generation tool (xsd.exe).
Be careful before splitting the generated classes, read the Serialization
section on MSDN :

A helper class creates an HTTP request with basic authentication to get the feed :

          //object to hold twitter response 
          Statuses statuses
= null; //request
to twitter service HttpWebRequest request
= (HttpWebRequest)
WebRequest.Create("http://twitter.com/statuses/friends_timeline.xml"); //authentication
info CredentialCache authInfo = newCredentialCache();
authInfo.Add(newUri(http://twitter.com/statuses/friends_timeline.xml),

"Basic", newNetworkCredential(username,
password)); request.Credentials = authInfo; //make
the call WebResponse response =
request.GetResponse(); //deserialize response XmlSerializer mySerializer
= newXmlSerializer(typeof(Statuses));
statuses = (Statuses)mySerializer.Deserialize(response.GetResponseStream());
response.Close(); listStatut = newList<Status>(statuses.status);

This method is called by the ObjectDataProvider which
provides the user and password :

          <
          ObjectDataProvider
           x
          :
          Key
          ="TwitterDataSource"
           d
          :
          IsDataSource
          ="True"
          
            

ObjectType
          ="{x:Type TwitterWPF:TwitterManager}"
           MethodName
          ="GetStatuses"> 
           <
          ObjectDataProvider
          .
          ConstructorParameters
          > 
           <
          sys
          :
          String
          >
          user
          </
          sys
          :
          String
          > 
           <
          sys
          :
          String
          >
          password
          </
          sys
          :
          String
          > 
           </
          ObjectDataProvider
          .
          ConstructorParameters
          >
          
          
          </
          ObjectDataProvider
          >
        

This class puts the collection returned in an ObservableCollection object
that provides notification when an item is added or removed. This can be useful
since we want to refresh the UI with a timer to get new statuses from Twitter.

I found severalarticles to
design items with alternate backgrounds in a ListView but
none works for me. They overwrite the style property of the items and they will
hide the background of the border. This border
is used to simulate rounded panels around the text :

          <
          ListView
          .
          ItemTemplate
          > 
          
          
          <
          DataTemplate
          >

          <
          Border
           Width
          ="400"
           Height
          ="75"
           CornerRadius
          ="10,10,10,10"
           Margin
          ="4,4,4,4"
          
            

Padding
          ="4,4,4,4" 
          Background
          ="{Binding
RelativeSource={RelativeSource AncestorType=ListViewItem},

Converter={StaticResource backgroundConverter}}"> 
          
          
          <
          Grid
           x
          :
          Name
          ="statusBox"
           Height
          ="auto"
           Width
          ="auto"> 
          
          
          <
          Grid
          .
          ColumnDefinitions
          > 
          
          
          <
          ColumnDefinition
           Width
          ="0.168*"
/> 
          
          
          <
          ColumnDefinition
           Width
          ="0.832*"
/> 
          
          
          </
          Grid
          .
          ColumnDefinitions
          > 
          
          
          <
          Grid
          .
          RowDefinitions
          > 
          
          
          <
          RowDefinition
          />
          
          
          </
          Grid
          .
          RowDefinitions
          >
          
          
          <
          Image
           Source
          ="{Binding
Path=User.ProfileImageUrl}"
          
            

Grid
          .
          Column
          ="0"
           Grid
          .
          Row
          ="0"
           x
          :
          Name
          ="userImage"/>
          
          
          <
          Label
           Margin
          ="8,0,8,0"
           x
          :
          Name
          ="status"
           Grid
          .
          Column
          ="1"
> 
          
          
          <
          TextBlock
           TextWrapping
          ="WrapWithOverflow"
          
            

Text
          ="{Binding Path=Text}"></
          TextBlock
          > 
          
          
          </
          Label
          >
          
          
          </
          Grid
          > 
          
          
          </
          Border
          > 
          
          
          </
          DataTemplate
          > 
          </
          ListView
          .
          ItemTemplate
          >
        

So I built an implementation of IValueConverter to
convert the binding of the background value property. I need to know the current ListViewItem,
so I provide the ancestor of type ListViewItem as the object to be converted. The
converter class finds its index inside the ListView and returns the color accordingly
:

          public
          object Convert(object value, Type targetType,

object parameter, System.Globalization.CultureInfo culture)
{ ListViewItem item = (ListViewItem)value; ListView listView
= ItemsControl.ItemsControlFromItemContainer(item) asListView; //
Get the index of a ListViewItem int index
= listView.ItemContainerGenerator.IndexFromContainer(item); if (index
% 2 == 0) { returnBrushes.LightBlue;
} else  { returnBrushes.Beige;
} }

The last thing to add is the call to refresh the list of the statuses : I put
a timer that refreshes both the  ObjectDataProvider and the ListView (without
the latter the index property is not correctly returned in the converter method) :

          void TimerClock_Tick(object sender, EventArgs e)
{ ObjectDataProvider odp = Resources["TwitterDataSource"] asObjectDataProvider;
odp.Refresh(); ICollectionView dataView
= CollectionViewSource.GetDefaultView(statusList.ItemsSource);
dataView.Refresh(); }

As I said, there are surely other ways to do this, maybe even more efficiently.
But the Twitter API returning only the 20 latest statuses,  efficiently is not
an issue. And it’s a good thing because I’m still discovering the WPF world.

download
the Visual Studio Orcas solution (beta1).

L’ami
Sami a bien décrit notre récente expérience de développement d’un projet "Web
2.0" avec GWT. Je rajouterai quelqes liens vers des ressources GWT qui facilitent
le développement. Les composants de base du framework sont nombreux mais la communauté
autour de GWT est très active.

• GWT Widget
  Library : composants pour la couche cliente (DataGrid avec pagination/ sorting,
  intégration de Google Maps) et serveur (intégration de Spring). Comme beaucoup d’autres
  composants la documentation est presque inexistante, la consultation du forum de GWT
  est indispensable. 
• Rocket : plus axé
  vers les composants graphiques
• Ajax solutoire :
  un site consacré aux technos Ajax avec ue rubrique GWT
• gwt-powered :
  annuaire de widgets et composants GWT, contient aussi une liste de sites construits
  autour de GWT. 

pastebin – collaborative debugging tool est un site qui permet de partager des extraits de code quand par exemple on a besoin d’aide sur un point particulier. Cela évite de s’envoyer des fichiers texte