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The Java Portlet API (JSR 168)
* <p>
* In this case, we will dispatch the method to a JSP
* located in the portlet root directory called “view.jsp”
*/
protected void doView(RenderRequest request,
RenderResponse response)
throws PortletException, IOException {
PortletRequestDispatcher prd =
getPortletContext().getRequestDispatcher(“/view.jsp”);
prd.include(request, response);
}
Similarly, we provide the behavior required to render the portlet when it is in its HELP and VIEW modes.
/* This method was overriden to specify
* the title programmatically
* This may be useful if you are going to
* have parameters in your title like:
* “News on 9/11/2001”
*/
protected String getTitle(RenderRequest request) {
return “Example Portlet”;
}
/* This method is the meat of the portlet
* manipulations of the portlet’s state are done
* through this method.
*
* For simplicity sake, we will parse a param
* that indicates the portlet mode to which the
* portlet should be set.
*
*/
public void processAction(ActionRequest request,
ActionResponse response)
throws PortletException, IOException {
PortletMode mode =
new PortletMode(request.getParameter(“mode”));
response.setPortletMode(mode);
}
}
Finally, we specify overriding the getTitle method, allowing for more complex logic in rendering the
title (such as displaying the current date) rather than displaying the static title declared in the deployment descriptor. We also handle the processAction method, which is responsible for the behavior in
response to an ActionRequest.
The preceding code shows a basic implementation of a portlet by writing a class that extends Generic
Portlet. This portlet doesn’t do much beyond dispatch to other JSPs based on its mode (and set its
name programmatically), but you see the crux of implementing a portlet.
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