Defining Portlet Actions

You need to add action methods to the Guestbook Admin portlet for adding, updating, and deleting guestbooks. The portlet action methods call the corresponding service methods. Using Service Builder in your guestbook-portlet project has provided your project with a service-oriented architecture. Note that due to Liferay’s service-oriented architecture, different portlets or web applications can call the same services. Since you’re about to design the Guestbook Admin portlet to consume one of the same services consumed by the Guestbook portlet (the addGuestbook service), you’re about to take advantage of one tangible benefit of Liferay’s service-oriented architecture. Of course, there are many other benefits to having a service-oriented architecture, such as the fact that it provides a clean separation of concerns. Portlet classes should not communicate directly with the database or the persistence layer. Instead, they should call services. Services can call the persistence layer to invoke database transactions.

Adding Three Basic Portlet Actions

Your requirements for the Guestbook Admin portlet specify that the portlet must allow administrators to add guestbooks, update guestbooks, and delete guestbooks. It must also allow guestbook permissions to be configured. You can create portlet actions to meet the first three requirements by opening GuestbookAdminPortlet.java and following these steps:

1. Add the following portlet method for adding a new guestbook:

    public void addGuestbook(ActionRequest request, ActionResponse response)
                    throws PortalException, SystemException {
   
            ServiceContext serviceContext = ServiceContextFactory.getInstance(
                            Guestbook.class.getName(), request);
   
            String name = ParamUtil.getString(request, "name");
   
            try {
                    GuestbookLocalServiceUtil.addGuestbook(serviceContext.getUserId(),
                                    name, serviceContext);
   
                    SessionMessages.add(request, "guestbookAdded");
            } catch (PortalException e) {
                    SessionErrors.add(request, e.getClass().getName());
   
                    response.setRenderParameter("mvcPath",
                                    "/html/guestbookadmin/edit_guestbook.jsp");
            }
    }
   

   This method is nearly identical to the Guestbook portlet’s addGuestbook method. Since addGuestbook is a portlet action method, it takes ActionRequest and ActionResponse parameters. In order to make the service call to add a new guestbook, the name of the Guestbook must be retrieved from the request. The serviceContext must also be retrieved from the request and passed as an argument in the service call. If there’s a problem with adding the Guestbook (an invalid or blank guestbook name, for example), you should display the Add Guestbook form and not the default view. That’s why you add this line in the catch block:

    response.setRenderParameter("mvcPath",
            "/html/guestbookadmin/edit_guestbook.jsp");
   

   Don’t worry about the fact that you haven’t created docroot/html/guestbookadmin/edit_guestbook.jsp yet; you’ll create it in the next section when you’re designing the Guestbook Admin portlet’s user interface.

2. Add the following portlet method for updating an existing guestbook’s name:

    public void updateGuestbook(ActionRequest request, ActionResponse response)
                    throws PortalException, SystemException {
   
            ServiceContext serviceContext = ServiceContextFactory.getInstance(
                            Guestbook.class.getName(), request);
   
            String name = ParamUtil.getString(request, "name");
            long guestbookId = ParamUtil.getLong(request, "guestbookId");
   
            try {
                    GuestbookLocalServiceUtil.updateGuestbook(serviceContext.getUserId(), 
                            guestbookId, name, serviceContext);
   
                    SessionMessages.add(request, "guestbookUpdated");
            } catch (PortalException pe) {
                    SessionErrors.add(request, pe.getClass().getName());
   
                    response.setRenderParameter("mvcPath",
                                    "/html/guestbookadmin/edit_guestbook.jsp");
            }
    }
   

   This method is very similar to the addGuestbook method. In addition to retrieving the guestbook name and the serviceContext from the request, the updateGuestbook method also retrieves the guestbookId so that it can specify which guestbook to update in the service call. If there’s a problem with the service call, the Guestbook Admin portlet displays the Edit Guestbook form again so that the user can edit the form and resubmit:

    response.setRenderParameter("mvcPath",
            "/html/guestbookadmin/edit_guestbook.jsp");
   

   Note that the Edit Guestbook form uses the same JSP as the Add Guestbook form. The reason for this is to avoid duplication of code. When you’re creating the Guestbook Admin portlet user interface, you’ll see how to distinguish between adding a guestbook and editing a guestbook in edit_guestbook.jsp. Note also that while you could have reused the edit_guestbook.jsp from the Guestbook portlet, you created another one, with almost the same functionality. Why? Because later, you’ll be adding functionality to the Guestbook Admin portlet that will not be available to regular users adding guestbooks.

3. Add the following portlet method for deleting a guestbook:

    public void deleteGuestbook(ActionRequest request, ActionResponse response)
                    throws PortalException, SystemException {
   
            ServiceContext serviceContext = ServiceContextFactory.getInstance(
                            Guestbook.class.getName(), request);
   
            long guestbookId = ParamUtil.getLong(request, "guestbookId");
   
            try {
                    GuestbookLocalServiceUtil.deleteGuestbook(guestbookId, serviceContext);
   
                    SessionMessages.add(request, "guestbookDeleted");
            } catch (PortalException pe) {
                    SessionErrors.add(request, pe.getClass().getName());
            }
    }
   

   This method is similar to the addGuestbook and updateGuestbook methods that you added above. Its service call requires only the serviceContext and the guestbookId, so these are retrieved from the request. Since the deleteGuestbook action is invoked from the default view of the Guestbook Admin portlet, there’s no need to set the mvcPath render parameter to point to a particular JSP if there was a problem with the deleteGuestbook service call.

You now have your service methods and your portlet action methods in place. Your last task is to implement a user interface for the Guestbook Admin portlet. Along the way, you’ll learn how to create an interface for configuring Guestbook permissions.