Updating Your Service Layer

In an earlier learning path, you wrote an addGuestbook service method in GuestbookLocalServiceImpl. The addGuestbook method of GuestbookPortlet calls this service method. You can reuse the addGuestbook method of GuestbookLocalServiceImpl by calling it from GuestbookAdminPortlet too. However, you need to add a new service method for updating a guestbook and a new service method for deleting a guestbook. You also need to add a service method that returns the number of guestbooks in a site. You’ll use this service method when you’re implementing your user interface since you’ll use a Liferay tag library construct called Search Container. Your search container needs to know how many guestbooks to display.

Adding Guestbook Service Methods

Remember that when working with Service Builder, the *Impl classes are your extension points. After you add or remove a method from an *Impl class or change a method signature of an *Impl class, you must run Service Builder. Service Builder updates the affected interfaces and any other affected generated code.

Use the following steps to add the required Guestbook service methods:

1. Open GuestbookLocalServiceImpl.java and add the following method for updating a guestbook:

    public Guestbook updateGuestbook(long userId, long guestbookId,
    String name, ServiceContext serviceContext) throws PortalException,
                    SystemException {
   
            Date now = new Date();
   
            validate(name);
   
            Guestbook guestbook = getGuestbook(guestbookId);
   
            User user = UserLocalServiceUtil.getUser(userId);
   
            guestbook.setUserId(userId);
            guestbook.setUserName(user.getFullName());
            guestbook.setModifiedDate(serviceContext.getModifiedDate(now));
            guestbook.setName(name);
            guestbook.setExpandoBridgeAttributes(serviceContext);
   
            guestbookPersistence.update(guestbook);
   
            resourceLocalService.updateResources(serviceContext.getCompanyId(),
                            serviceContext.getScopeGroupId(), name, guestbookId,
                            serviceContext.getGroupPermissions(),
                            serviceContext.getGuestPermissions());
   
            return guestbook;
    }
   

   The updateGuestbook service method is similar to the updateEntry service method in EntryLocalServiceImpl. As with guestbook entries, you not only must update the guestbook model itself, but also must update the guestbook’s resources. If your updateGuestbook service method didn’t update a guestbook’s resources, permissions updates for guestbooks would not be possible.

2. Next, add the following method for deleting a guestbook:

    public Guestbook deleteGuestbook(long guestbookId,
                    ServiceContext serviceContext) throws PortalException,
                    SystemException {
   
            Guestbook guestbook = getGuestbook(guestbookId);
   
            List<Entry> entries = EntryLocalServiceUtil.getEntries(
                            serviceContext.getScopeGroupId(), guestbookId);
   
            for (Entry entry : entries) {
                    EntryLocalServiceUtil.deleteEntry(entry.getEntryId(),
                                    serviceContext);
            }
   
            resourceLocalService.deleteResource(serviceContext.getCompanyId(),
                            Guestbook.class.getName(), ResourceConstants.SCOPE_INDIVIDUAL,
                            guestbookId);
   
            guestbook = deleteGuestbook(guestbook);
   
            return guestbook;
    }
   

   It’s important to consider what should happen if you delete a guestbook for which there are existing entries. If you just deleted the guestbook, the guestbook’s entries would still exist in the database, but they would be orphaned. Your deleteGuestbook service method makes a service call to delete all the entries associated with a guestbook before deleting the guestbook itself. This way, guestbook entries are never orphaned.

3. Finally, add the following method for returning the number of guestbooks in a site:

    public int getGuestbooksCount(long groupId) throws SystemException {
            return guestbookPersistence.countByGroupId(groupId);
    }
   

   guestbookPersistence, like resourceLocalService, is a Spring bean declared in GuestbookLocalServiceImpl’s parent class, GuestbookLocalServiceBaseImpl. The guestbookPersistence implementation class is GuestbookPersistenceImpl, which is one of the classes generated by Service Builder. GuestbookPersistenceImpl contains the countByGroupId method that you use in the getGuestbooksCount service method.

These are all the additions you need to make to the Guestbook service. Save GuestbookLocalServiceImpl.java and run Service Builder.

Now that you’ve finished updating the service layer, it’s time to work on the Guestbook Admin portlet itself.