02-implementing-a-guestbook-asset-renderer.markdown

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implementing-a-guestbook-asset-renderer

Implementing a Guestbook Asset Renderer

[TOC levels=1-4]

Implementing Asset Renderers

Step 1 of 2

@product@'s asset renderers follow the factory pattern, so you must create a GuestbookAssetRendererFactory that instantiates the GuestbookAssetRenderer's private guestbook object. Here, you'll create both classes.

You'll create the Asset Renderer class first.

Creating the AssetRenderer Class

Follow these steps to create the GuestbookAssetRenderer class:

1. Create a new package called com.liferay.docs.guestbook.web.internal.asset in the guestbook-web module's src/main/java folder. In this package, create a GuestbookAssetRenderer class that extends @product@'s BaseJSPAssetRenderer class. Extending this class gives you a head-start on implementing the AssetRenderer interface:

   public class GuestbookAssetRenderer extends BaseJSPAssetRenderer<Guestbook> {
   
   }

2. Add the constructor, the guestbook class variable, and the permissions model resource. Most of the methods in this class are getters that return fields from the private _guestbook object. Methods requiring a permission check use _guestbookModelResourcePermission:

   public GuestbookAssetRenderer(Guestbook guestbook, ModelResourcePermission<Guestbook> modelResourcePermission) {
   
               _guestbook = guestbook;
               _guestbookModelResourcePermission = modelResourcePermission;
   }
   
   // Add the other methods here
   
   private Guestbook _guestbook;
   private final ModelResourcePermission<Guestbook> _guestbookModelResourcePermission;   
   private Logger logger = Logger.getLogger(this.getClass().getName());

3. The BaseJSPAssetRenderer abstract class that you're extending contains dummy implementations of the hasEditPermission and hasViewPermission methods that you must override with actual permission checks using the permissions resources that you created earlier. Add these methods below the comment labeled Add the other methods here:

   @Override
   public boolean hasEditPermission(PermissionChecker permissionChecker) 
   {
       try {
           return _guestbookModelResourcePermission.contains(
               permissionChecker, _guestbook, ActionKeys.UPDATE);
       }
       catch (Exception e) {
       }
   
       return false;
   }
   
   @Override
   public boolean hasViewPermission(PermissionChecker permissionChecker) 
   {
       try {
           return _guestbookModelResourcePermission.contains(
               permissionChecker, _guestbook, ActionKeys.VIEW);
       }
       catch (Exception e) {
       }
   
       return true;
   }

4. Add the following getter methods to retrieve information about the guestbook asset:

   @Override
   public Guestbook getAssetObject() {
     return _guestbook;
   }
   
   @Override
   public long getGroupId() {
     return _guestbook.getGroupId();
   }
   
   @Override
   public long getUserId() {
   
     return _guestbook.getUserId();
   }
   
   @Override
   public String getUserName() {
     return _guestbook.getUserName();
   }
   
   @Override
   public String getUuid() {
     return _guestbook.getUuid();
   }
   
   @Override
   public String getClassName() {
     return Guestbook.class.getName();
   }
   
   @Override
   public long getClassPK() {
     return _guestbook.getGuestbookId();
   }
   
   @Override
   public String getSummary(PortletRequest portletRequest, PortletResponse 
     portletResponse) {
       return "Name: " + _guestbook.getName();
   }
   
   @Override
   public String getTitle(Locale locale) {
     return _guestbook.getName();
   }
   
   @Override
   public boolean include(HttpServletRequest request, HttpServletResponse 
     response, String template) throws Exception {
       request.setAttribute("GUESTBOOK", _guestbook);
       request.setAttribute("HtmlUtil", HtmlUtil.getHtml());
       request.setAttribute("StringUtil", new StringUtil());
       return super.include(request, response, template);
   }

   The final method makes several utilities and the Guestbook entity available in the HttpServletRequest object.

5. Override the getJspPath method. It returns a string representing the path to the JSP that renders the guestbook asset. When the Asset Publisher displays an asset's full content, it invokes the asset renderer class's getJspPath method and passes a template string parameter that equals "full_content". This returns /asset/guestbook/full_content.jsp when the full_content template string is passed as a parameter. You'll create this JSP later when updating your application's user interface:

   @Override
   public String getJspPath(HttpServletRequest request, String template) {
   
       if (template.equals(TEMPLATE_FULL_CONTENT)) {
         request.setAttribute("gb_guestbook", _guestbook);
   
         return "/asset/guestbook/" + template + ".jsp";
       } else {
         return null;
       }
   }

6. Override the getURLEdit method. This method returns a URL for editing the asset:

   @Override public PortletURL getURLEdit(LiferayPortletRequest liferayPortletRequest, LiferayPortletResponse liferayPortletResponse) throws Exception {

   PortletURL portletURL = liferayPortletResponse.createLiferayPortletURL(
       getControlPanelPlid(liferayPortletRequest), GuestbookPortletKeys.GUESTBOOK,
       PortletRequest.RENDER_PHASE);
   portletURL.setParameter("mvcPath", "/guestbook/edit_guestbook.jsp");
   portletURL.setParameter("guestbookId", String.valueOf(_guestbook.getGuestbookId()));
   portletURL.setParameter("showback", Boolean.FALSE.toString());
   
   return portletURL;
   

   }

7. Override the getURLViewInContext method. This method returns a URL to view the asset in its native application:

   @Override
   public String getURLViewInContext(LiferayPortletRequest liferayPortletRequest,
     LiferayPortletResponse liferayPortletResponse, String noSuchEntryRedirect) throws Exception {
       try {
         long plid = PortalUtil.getPlidFromPortletId(_guestbook.getGroupId(),
             GuestbookPortletKeys.GUESTBOOK);
   
         PortletURL portletURL;
         if (plid == LayoutConstants.DEFAULT_PLID) {
           portletURL = liferayPortletResponse.createLiferayPortletURL(getControlPanelPlid(liferayPortletRequest),
               GuestbookPortletKeys.GUESTBOOK, PortletRequest.RENDER_PHASE);
         } else {
           portletURL = PortletURLFactoryUtil.create(liferayPortletRequest,
               GuestbookPortletKeys.GUESTBOOK, plid, PortletRequest.RENDER_PHASE);
         }
   
         portletURL.setParameter("mvcPath", "/guestbook/view.jsp");
         portletURL.setParameter("guestbookId", String.valueOf(_guestbook.getGuestbookId()));
   
         String currentUrl = PortalUtil.getCurrentURL(liferayPortletRequest);
   
         portletURL.setParameter("redirect", currentUrl);
   
         return portletURL.toString();
   
       } catch (PortalException e) {
   
           logger.log(Level.SEVERE, e.getMessage());
   
       } catch (SystemException e) {
   
           logger.log(Level.SEVERE, e.getMessage());
   
       }
   
       return noSuchEntryRedirect;
   }

8. Override the getURLView method. This method returns a URL to view the asset from within the Asset Publisher:

   @Override
   public String getURLView(LiferayPortletResponse liferayPortletResponse, 
   WindowState windowState) throws Exception {
   
       return super.getURLView(liferayPortletResponse, windowState);
   }

9. Organize imports (Ctrl-Shift-O) and save the file. Choose these imports:

- `java.util.logging.Logger` 
- `com.liferay.portal.kernel.exception.SystemException` 
- `java.util.logging.Level` 
- `com.liferay.petra.string.StringUtil`

Next you can create the AssetRendererFactory class.

Creating the GuestbookAssetRendererFactory Class

Follow these steps to create the GuestbookAssetRendererFactory:

1. In the com.liferay.docs.guestbook.web.internal.asset package, create a class called GuestbookAssetRendererFactory that extends @product@'s BaseAssetRendererFactory class, and overwrite the generated constructor and class variables with this:

   @Component(immediate = true, 
     property = {"javax.portlet.name=" + GuestbookPortletKeys.GUESTBOOK}, 
     service = AssetRendererFactory.class
     )
   public class GuestbookAssetRendererFactory extends 
     BaseAssetRendererFactory<Guestbook> {
   
     public GuestbookAssetRendererFactory() {
       setClassName(CLASS_NAME);
       setLinkable(_LINKABLE);
       setPortletId(GuestbookPortletKeys.GUESTBOOK); setSearchable(true);
       setSelectable(true); 
     }         
    
     // Add the other methods here
   
     private ServletContext _servletContext;
     private GuestbookLocalService _guestbookLocalService;
     private static final boolean _LINKABLE = true;
     public static final String CLASS_NAME = Guestbook.class.getName();
     public static final String TYPE = "guestbook";
     private Logger logger = Logger.getLogger(this.getClass().getName());
     @Reference(target = "(model.class.name=com.liferay.docs.guestbook.model.Guestbook)")
     private ModelResourcePermission<Guestbook> _guestbookModelResourcePermission;
   }

   This code contains the class declaration, the constructor, and the class variables. It sets the class name it creates an AssetRenderer for, a portlet ID, and a true boolean (_LINKABLE). The boolean denotes implemented methods that provide URLs in the generated AssetRenderer.

   Insert the methods below where you see the comment Add the other methods here.

2. Implement the getAssetRenderer method, which constructs new GuestbookAssetRenderer instances for particular guestbooks. It uses the classPK (primary key) parameter to retrieve the guestbook from the database. It then calls the GuestbookAssetRenderer's constructor, passing the retrieved guestbook and permissions resource model as arguments:

   @Override
   public AssetRenderer<Guestbook> getAssetRenderer(long classPK, int type) 
   throws PortalException {
     
     Guestbook guestbook = _guestbookLocalService.getGuestbook(classPK);
   
     GuestbookAssetRenderer guestbookAssetRenderer = 
     new GuestbookAssetRenderer(guestbook, _guestbookModelResourcePermission);
   
     guestbookAssetRenderer.setAssetRendererType(type);
     guestbookAssetRenderer.setServletContext(_servletContext);
   
     return guestbookAssetRenderer;
   }

3. You're extending BaseAssetRendererFactory, an abstract class that implements the AssetRendererFactory interface. To ensure that your custom asset is associated with the correct entity, each asset renderer factory must implement the getClassName and getType methods (among others):

   @Override
   public String getClassName() {
       return CLASS_NAME;
   }
   
   @Override
   public String getType() {
       return TYPE;
   }

4. Implement the hasPermission method:

   @Override
   public boolean hasPermission(PermissionChecker permissionChecker, 
   long classPK, String actionId) throws Exception {
     Guestbook guestbook = _guestbookLocalService.getGuestbook(classPK);
     return _guestbookModelResourcePermission.contains(permissionChecker, guestbook.getGuestbookId(), 
     actionId);
   }

5. Add the remaining code to create the portlet URL for the asset and specify whether it's linkable:

   @Override
   public PortletURL getURLAdd(LiferayPortletRequest liferayPortletRequest,
     LiferayPortletResponse liferayPortletResponse, long classTypeId) {
       PortletURL portletURL = null;
   
       try {
         ThemeDisplay themeDisplay = (ThemeDisplay) 
         liferayPortletRequest.getAttribute(WebKeys.THEME_DISPLAY);
   
         portletURL = liferayPortletResponse.createLiferayPortletURL(getControlPanelPlid(themeDisplay),
             GuestbookPortletKeys.GUESTBOOK, PortletRequest.RENDER_PHASE);
         portletURL.setParameter("mvcPath", "/guestbook/edit_guestbook.jsp");
         portletURL.setParameter("showback", Boolean.FALSE.toString());
   
         } catch (PortalException e) {
         
               logger.log(Level.SEVERE, e.getMessage()); 
               
         }
   
       return portletURL;
   }
   
   @Override
   public boolean isLinkable() {
       return _LINKABLE;
   }
   
   @Override
   public String getIconCssClass() {
     return "bookmarks";
   }
   
   @Reference(target = "(osgi.web.symbolicname=com.liferay.docs.guestbook.portlet)",
       unbind = "-")
   public void setServletContext(ServletContext servletContext) {
       _servletContext = servletContext;
   }
   
   @Reference(unbind = "-")
   protected void setGuestbookLocalService(GuestbookLocalService guestbookLocalService) {
       _guestbookLocalService = guestbookLocalService; 
   }

6. Organize imports (Ctrl-Shift-O) and save the file. Select these imports:

   • java.util.logging.Logger
   • java.util.logging.Level

Great! The guestbook asset renderer is complete. Next, you'll create the entry asset renderer.