RC Faces Servlet

Rcfaces resources Servlet

RC Faces works with a servlet named "Rcfaces resources Servlet". This role is to load stylesheets, javascript and images used by the RCFaces components.
Register this servlet like this in web.xml :

 <servlet>

    <servlet-name>Rcfaces resources Servlet</servlet-name>

    <servlet-class>org.rcfaces.renderkit.html.internal.resource.ResourcesServlet</servlet-class>

    <load-on-startup>1</load-on-startup>

 </servlet>

    

 <servlet-mapping>

     <servlet-name>Rcfaces resources Servlet</servlet-name>

     <url-pattern>/rc-fwk/*</url-pattern>

 </servlet-mapping>

Rcfaces Application version

The size of HTTP exchanges tends to increase with modern Web applications.

To minimize the network traffic, RC Faces can add expiration dates to the static resources (JavaScript, css, images, ...) used by JSF components.


With expiration dates, the browser or the proxy server will put the RC Faces resources in a cache and will not make further requests for those resources.


The main problem with this mechanism is the deployment of a new version of an application. If the cached resources have been modified, there is normally no way to tell the proxy or the browsers to clear their cache immediatly !

 

The role of the Application Version Servlet (AVS) is to get around this problem. To do so the AVS manage HTTP header for each RcFaces resource (Last Modified, Expires date, a special calculation of Etag and the content-MD5 attributes). It will also change the URL of the resources whenever a new version of an application is deployed. The change of URL will force the browser and the proxy server to get a new version of all the resources used by an application.

            

Register this servlet like this :


 <servlet>

    <servlet-name>Rcfaces Application version</servlet-name>

   <servlet-class> org.rcfaces.core.internal.version.ApplicationVersionServlet</servlet-class>

   <load-on-startup>1</load-on-startup>

 </servlet>

    

<servlet-mapping>

    <servlet-name>Rcfaces Application version</servlet-name>

    <url-pattern>/rc-av/*</url-pattern>

</servlet-mapping>

You can force the application version in web.xml :

<context-param>

    <param-name>org.rcfaces.core.APPLICATION_VERSION</param-name>

    <param-value>hashcode</param-value>

        <!-- param-value>v10.0</param-value -->

        <!-- param-value>v10.1</param-value -->

</context-param>

 
An URL looks like :"http://myproject/rc-av/<hashcode>/myResource.gif"    

Note: If the size of resource is greater than 512ko so the AVS use gzip compression over HTTP.        

Rcfaces Application dynamics Contents

RC Faces has a servlet to manage Css file. The first role of this servlet is to merge all the CSS files needed by an application in a single file. In this way web browsers don't have to load too many files. 


The generation of this single CSS file can be a time-consuming task.  To maximize the application performance, the Application Content Servlet caches the generated CSS file in memory.     


Register this servlet like this :


 <servlet>

    <servlet-name>Rcfaces Application Contents</servlet-name>

   <servlet-class> org.rcfaces.core.internal.contentStorage.ContentStorageServlet</servlet-class>

   <load-on-startup>1</load-on-startup>

 </servlet>

    

<servlet-mapping>

    <servlet-name>Rcfaces Application Contents</servlet-name>

    <url-pattern>/rc-content/*</url-pattern>

</servlet-mapping>

 

The second Role of the Application Content Dynamics Servlet is to modify dynamically an image. 


The servlet allows to :

  • Change colors depending the image state.
  • Change contrast and brightness for differents type of image files.
  • Resize images.
  • Convert an image to another format  (JPEG, GIF, PNG and ICO).

Sample page that uses the dynamic image features of the servlet :


<v:image imageURL="images/back64.gif" />                                  

<v:image imageURL="hover::images/back64.gif" />

<v:image imageURL="disabled::images/back64.gif" />

<v:image imageURL="selected::images/back64.gif" />

<v:image imageURL="gray::images/back64.gif" />


<v:image imageURL="contrast(0.6)::images/back64.gif" />

<v:image imageURL="brithness(-0.6)::images/back64.gif" />

 

<v:image imageURL="scale(0.5)::images/back64.gif" />

 

<!--size in px  -->

<v:image imageURL="resize(50)::images/back64.gif" />

<v:image imageURL="setSize(80,150)::images/back64.gif" />


<v:imageCheckButton

    imageURL="images/home.gif"

    hoverImageURL="hover::"

    disabledImageURL="disabled::"

    selectedImageURL="selected::"

/>


<v:imageCheckButton disabled="true"

    imageURL="images/home.gif"

    disabledImageURL="disabled::"

/>



<!--GIF to JPEG  -->

<v:image imageURL="jpeg(quality=1)::images/babelfish.gif" />


<!--JPEG to JPEG  -->

<v:image imageURL="jpeg(quality=0.7)::images/babelfish.jpg" />


<!--JPEG to GIF -->

<v:image imageURL="gif::images/babelfish.jpg" />


<!--JPEG to PNG -->

<v:image imageURL="png::images/babelfish.jpg" />


<!--GIF to PNG  -->

<v:image imageURL="png::images/babelfish.gif" />



 

Results :

    original      hover     disabled    selected     gray

   contrast   brithness scale resize setsize

Rcfaces Client bundle

Internationalization is an important feature for a web based application. JSF standard tag <f:loadBundle> allows to do perform basic internationalization. However it isn't available for JavaScript programming.
RC faces client bundle servlet's goal is to make the resources bundle available for JavaScript Programming.
   
Register the "RCFaces Client Bundle" servlet like this :  

 <servlet>

    <servlet-name>Rcfaces client bundle</servlet-name>

   <servlet-class> org.rcfaces.html.internal.clientBundle.clientResourceBundleServlet</servlet-class>

   <load-on-startup>1</load-on-startup>

 </servlet>

    

<servlet-mapping>

    <servlet-name>Rcfaces Client bundle</servlet-name>

    <url-pattern>/rc-cb/*</url-pattern>

</servlet-mapping>

 

In Faces-Config.xml  declare all the needed locales : 


 <application>

     <locale-config>

         <default-locale>en</default-locale>

         <supported-locale>fr</supported-locale>

         <supported-locale>de</supported-locale>

     </locale-config>

 </application>

 

Exemple :

Sample messages.properties file (in the "bundle" package) :

greeting_text=Greeting

forfun_alert=Framework created by Olivier Oeuillot

test=java is {0} and {1}


Sample JSP : 

 

<vh:loadBundle bundleName="messages"  baseName="bundle.Messages" />

<script>

      var bundle=f_resourceBundle.Get("messages");

     

      try {

            alert("Bundle="+bundle.f_format("forfun_alert"));

            alert("Bundle="+bundle.f_format("test", "good", "powerfull" )); 

      } catch (x) {

            alert("Test: "+x);

      }

</script>

 

<v:textEntry id="demoText" value="#{messages.greeting_text}"  required="true">

      <v:text for="demoText"  text="Label : "/>

</v:textEntry>

 
This feature allows JavaScript access to resource bundles deployed on server.