With the release of JSF 2 and ICEfaces 3, a common situation arises of porting and converting existing ICEfaces 1.8.x applications. This tutorial will demonstrate the required steps to convert a legacy application to "compat mode" in ICEfaces 3. This means you can still use your existing ice: components and backing beans, but aren't yet taking advantage of ICEfaces 3 specific features and benefits. The majority of the conversion effort involves configuration files and libraries, so most of your page markup won't need to be significantly changed.
This tutorial assumes the reader has a basic understanding of JSF and ICEfaces, especially creating and working with projects related to those technologies. The focus is not to teach the foundations, but instead to learn about porting applications. More information about porting can also be found here.
The goal of this tutorial is to examine a real world ICEfaces 1.8.x application. Once we have an understanding of the project we will begin the steps to port the application to ICEfaces 3. The application is a slightly modified version of the "jobApplication" used in the ICEfaces Online Training. There is a central form based page that can redirect to two pages based on different outcomes.
The following tools were used to create the project.
Download and extract the above source code bundle, and Import -> Existing Project into Workspace the folder into your Eclipse instance. Build and deploy the application to your Tomcat instance, and navigate to the deployed jobApplication. You will see a page similar to the following:
Now let's examine the page code, to get a better idea of what the application is doing. There are three main pages:
The Java code is fairly standard for 1.8, focusing on two beans:
Now that we understand the project, we'll start the 1.8 to ICEfaces 3 conversion process. The steps below will help you understand the requirements of porting, and can be applied to any of your own projects.
Currently jobApplicaiton is using ICEfaces 1.8.2 and JSF 1.2. We will want to upgrade these versions to 3 and 2, respectively.
First remove references in our project to ICEfaces 1.8.2 and JSF 1.2. This will likely require Build Path changes inside Eclipse. The ICEfaces Core, Facelets, and Support Libraries 1.8.2 should be removed, as should JSF 1.2 Sun RI. The exact naming may be different in your project.
Download and extract the ICEfaces 3 bundle. Copy the following jar files from icefaces/lib to jobApplication/WEB-INF/lib/:
Copy the following jar files from icefaces/lib/compat to jobApplication/WEB-INF/lib/:
The primary jars are icefaces.jar and icefaces-compat.jar. The former contains all the ICEfaces 3 code we need, while the latter has compat specific code around ice: components.
Now we will add JSF 2. Copy the following jar file from icefaces/lib/mojarra to jobApplication/WEB-INF/lib/:
There will probably be a few errors within the project because of these changes. That's okay, we just need to modify the configuration and pages to be JSF 2 specific to resolve this problem.
With this tutorial application, this step is unnecessary, since it almost exclusively uses component tags and not html tags. But with other applications, that mix html tags amongst component tags, there is an issue with JSF 2 Facelets where html fragments become UIInstructions, such that one html tag could become several UIInstructions components, or several html tags could become one UIInstructions component, depending on their arrangement. There is no one-to-one mapping, like what exists with ICEfaces 1.x, where it ships with a modified Facelets implementation that addresses this issue.
If this application did combine html tags with component tags, and in particular h:panelGrid or ice:panelGrid, such as like this:
The expected component tree would be a <h:panelGrid> with a single <center> child tag, which itself would have a single <h:inputText> child. With standard JSF, what happens instead is that <h:panelGrid> has 3 children: a UIInstructions child corresponding to the opening <center> tag, the <h:inputText>, and a UIInstructions child corresponding to the closing </center> tag. The <h:panelGrid> component then renders each of its children into a separate <td> tag, which will confuse the browser, since the starting <center> will be in a separate <td> than the ending </center>.
If you're developing with ICEfaces EE, then the simplest solution is to include the ICEfaces EE Core Framework Extensions fix for this issue, which involves adding a jar to your war, and setting a context param in your web.xml.
Now we will change the XML configuration file faces-config.xml. The main changes will be scope related, to accomodate the new JSF 2 scopes.
First we'll update the faces-config.xml header to be 2, instead of 1.2. Near the top of the file replace:
As you can see we changed the version and schema location to 2.
Now we can remove the old reference to the D2DFaceletViewHandler, as this customization is handled transparently in ICEfaces 3. Remove the following line inside the <application> node:
Next we will modify the old <managed-bean-scope> nodes to conform to those available in ICEfaces 3. Previously ICEfaces 1.8.x used "extended request scope", which meant request was handled differently than it is now. The closest we can get to duplicating this functionality is using the JSF 2 view scope.
Change all 3 beans to have a scope of view:
Now we will change the XML configuration file web.xml. The main change will be servlet mappings and adding some context parameters for ICEfaces 3.
The previously declared Persistent Faces Servlet and Blocking Servlet are no longer needed in ICEfaces 3, as their functionality has changed and setup has been reduced. Remove all declarations and mappings for those two servlets:
In addition, the ContextEventRepeater is no longer required so the declaration for that listener can be removed as well:
As part of the compatibility requirements of porting a project, a new servlet will be added:
The purpose of the FacesServlet has changed between 1.8 and ICEfaces 3, and so the declaration and mapping must as well. Replace the old declaration:
With the new declaration and mapping:
The last change in web.xml is to change some of the context-param variables. Remove unnecessary parameters:
Add a pair of new context-param variables that help ICEfaces 3 act more like 1.8.x in regards to markup and validation:
Modify context-parameters that have changed. For example, while backward compatible, the old facelets.REFRESH_PERIOD parameter should be updated to the official javax.faces.FACELETS_REFRESH_PERIOD. The value is the number of seconds to wait before checking whether a facelets page should be recompiled. A value of -1 means never check:
The final change is to modify the page markup to conform to JSF 2 standards. These changes are mostly related to the header and format of the page, while all the ice: components can remain as they are.
The first page to change is the simplest, and that is modifying that page index.jsp redirects to. Change the old redirect:
To point to the new mapping extension of the applicationForm page:
The header, namespace, and body tags need to be modified to port 1.8 markup to JSF 2. Replace the following tags near the top of the page:
With the following:
Remember to replace all closing tags for the above changes.
This change is necessary because JSF 2 uses html as the parent container tag of a page, instead of f:view. Also, because AJAX is built in to JSF 2, h:head and h:body are required instead of the old plain HTML head and body.
Similary, the headers of our other two pages will need to be changed. Replace the old header code in both pages:
With a similar update:
As before, remember to update the closing tags as well.
The ice:outputDeclaration tag has been deprecated for ICEfaces 3 and should be replaced with the DOCTYPE tag. If it is present in your application, remove the following:
Replace it with:
Those are all the changes we needed! Overall porting 1.8 to ICEfaces 3 is fairly simple, and focuses more on configuration changes instead of being forced to modify your Java code or any functional markup.
Build and re-deploy the jobApplication and test it to ensure the functionality remains the same. From a user point of view the page will look the same, but now we're running on the modern ICEfaces 3!
The resulting code for the ICEfaces 3 version of the jobApplication is available if you need.
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