Developing Portlets with GWT

How to write a portlet with the aim of GWT.

Pre-development Actions

Modifying Tomcat

1. Replace $CATALINA_HOME/webapps/gridsphere/WEB-INF/CustomPortal/layouts/TemplateLayout.xml with the corresponding one found here.
2. Include gwt.js and script.html files found here in $CATALINA_HOME/webapps/gridsphere/html directory.

Modifying Gridpshere Home

If you want you can also apply the respective changes to gridsphere's home directory. This can be useful if, for some reason, you want to redeploy gridsphere.

Installing GWT

1. Download the latest version of GWT from here.
2. Uzip the file.
3. Set environmntal variable: GWT_HOME=<the name of the folder where you unpacked gwt files>

How to create a gwt-portlet

Create a gwt project

In order to create a gwt project, you must execute:

>cd $GRIDPSHERE_HOME/projects
>mkdir <module_dir_name>
>cd <module_dir_name>
>$GWT_HOME/projectCreator -eclipse MyProject
>$GWT_HOME/applicationCreator -eclipse MyProject org.diligentproject.<whatever>.client.<ModuleName>

Now you can develop your gwt project as you wish by using eclipse! FYI, there is a toolkit for eclipse that provides developers with a GUI so as to design their gwt modules. However, it's not free. If you wish to see its demos, click here.

You can find useful information about the Google Web Toolkit on its official site: http://code.google.com/webtoolkit/

Create a jsr 168 portlet

In oder to create an empty portlet project, you must execute:

>cd $GRIDPSHERE_HOME/
>ant new-project
    * insert: <Portlet's Title>
    * insert: <module_dir_name>  --- This must be the same as in gwt project
    * insert: jsr

Now, if you refresh the eclipse project, you can see that the "portlet-files" are generated.

Create the portlet class

• Create a class named: org.diligentproject.<whatever>.portlets.<portletClassName>
• Add the following content to the class:

// JSP folder name public static final String JSP_FOLDER = "/jsp"; // JSP file name to be rendered on the view mode

public static final String VIEW_JSP = JSP_FOLDER + "/<a_name_for_the_jsp_page>.jsp";




   public void doView(RenderRequest request, RenderResponse response) throws PortletException, IOException{

// ------------------------------------------------------------ // Note: The portlet is just diplaying a JSP for the AJAX Lab. // It does absolutely nothing else. // ------------------------------------------------------------

   	// Set the MIME type for the render response

//response.setContentType(request.getResponseContentType());

// Invoke the JSP to render

PortletRequestDispatcher rd = getPortletContext().getRequestDispatcher(VIEW_JSP); rd.include(request,response);

   }