Liferay 6 Certification Preparation Tips

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How to prepare

  • There is no shortcut. Don’t rely on any sample questions online(including this post) completely. Best way to prepare is to practice tutorial here . Even the experienced developers should try to go through the tutorial, try to create portlets, hooks and learn the concepts by doing things.
  • One question will definitely come from this blog post
  • At least 1-3 question will be around Liferay Lifecycle, Phases, Modes and States. Learn which ones are introduced in JSR-286
  • Hooks Hooks Hooks learn as much as possible about hooks.
  • Especially whether or not and how it can implement core JSP overwrites and custom action.
  • Learn about the tags in the liferay-hook.xml
  • Learn APIs for Util and User – for e.g., how to get organizations for a user OrganlizationServiceUtil.getUserOrganizations(long userId)
  • Learn about EXT practices – how to cleanly deploy in the production environment and how to deploy in development environment
  • liferay-portlet.xml, portlet.xml, portlet-custom.xml, portlet-ext.xml,, liferay-look-and-feel.xml – you understand about these files when you learn about them individually. But when you appear for the exam it is very very confusing.
  • Ext vs Hook. Be very clear what can be done in hook and what can be done in EXT. The exam comes to this tricky issue again and again
  • Don’t under estimate Layout Template and Theme sections. Read it from developer guide. It’s an easy win
  • It is a good idea to look into liferay-hook dtd and But practically speaking you won’t be able to remember all the possible portal-properties. Objective is to learn about as many of them as possible
Example Questions(Not exact questions from actual exams)
  • What is true – class in plugin has access to every class in portal, every class in portal-service plus plugin class, every class in portal-impl.jar plus plugin class etc.
  • What has to be done to prevent submission of form again?
  • What happens after a portlets action is called. Options are – render of only that portlet is called, render of all portlets on the page is called, render of any portlet whose data changed is called.
  • Expando is – service available to add custom attributes
  • How to get organizations associated to a user. Options are UserServiceUtil, OrganizationServiceUtil, SiteServiceUtil, All of the above etc. I have answered UserLocalServiceUtil.getOrganizations() .
    • The right answer is OrganlizationServiceUtil.getUserOrganizations(long userId)
  • companyId is – options are organization, site, portal etc.
    • Right answer – companyId represents a portal instance. Liferay can host multiple portals in a single database. companyId is primary key for a particular instance. In scope terms companyId is on top of the hierarchy, followed by GroupID which represents site or organization and then UserId, which identifies a user
  • There is a plugin portlet which required another plugin portlet how to ensure that.
    • Answer – is you will use  required-deployment-contexts in LEARN MORE about it.
  • There was a question about removing a portlet from whitelist which is mentioned in of the Portal. portlet.add.default.resource.check.whitelist . To remove one of the portlets from whitelist what has to be done.
    • This is important. Hooks can just add to the whitelist because properties are merged. To remove, you may have to create ext. Some properties are just mergeable not overrideable
  • Language properties for a locale en_Us is implemented. Now the language values for that particular locale will come from
    • Yes, the answer is plugin’s Language_en plus core Language_en
  • If you have to add a new field for indexing what would you do?
    • I think indexer post processor hook should do it.
  • What is the syntax for a custom-struts path in hook? I think I have answered this correctly. <!ELEMENT struts-action (struts-action-path, struts-action-impl)>. It involves structs-action-path root element with struts-action-path and struts-action-impl
  • When you override a JSP say view.jsp using hook what happens to original JSP.
    • Answer is that it gets replaced with view.portal.jsp
Layout templates
  • two questions on how to include portlet plugin in layout template – $processor.processPortlet with Fully Qualified Portlet Id
    • Please note that in theme you will include using theme.runtime(..)
  • Syntax of <liferay-ui:success key=”key” message=”message” /> was asked. I thought only key attribute is required.
    • As per dtd both key and message are required
  • How to escape special characters. For such questions, please learn about important utility methods in the following
    •  HtmlUtil
    • ParamUtil
    • GetterUtil
Development practices
  • how the base theme settings are imported.
    • Just set theme.parent in build.xml
  • Javascript method called after each portlet is executed.
    • Right answer is Liferay.Portlet.ready(fn) . This is an important question. This comes in one way or another. Link
  • AlloyUI is based on – answer is YUI3
  • How to remove portlet borders in custom theme
  • How to embed a portlet in theme. Answer is theme.runtime()
  • Best way to undeploy / redeploy ext hook – I think best is to unzip clean portal
  • Best way to remove some customization from ext and deploy changes in development environment .
Service Builder
  • What are the services available/injected to each service generated by service builder. CounterLocalService, AssetLocalService, ResourceLocalService and two more..
    • Counter
    • Resource
    • User
  • There was one question where they wanted to strip out something from returned response. where can we do it? options were Request post processor in hook/ext, servlet filters, post action etc
    • It could be done by StripFilter and if the requirement is not met by that we can use servletfilter
    • It’s interesting, servlet filters can be used for both requests and responses
  • If you have to run a code which has to be run just once, where will you put it.
  • If you want to remove some core portlet from Add Portlet option to control panel what will you do.
  • A service.xml mapping was shown with entity something and localservice=true and remoteservice=false was asked what classes will be generated. In general, it’s better to understand what are the different classes which are generated in various options
    • Take example of Event entity
      • Persistence
        • EventPersistence
        • EventPersistenceImpl
        • EventUtil
      • Local Service
        • EventLocalService
        • EventLocalServiceImpl(CLASS TO BE MANUALLY CHANGED)
        • EventLocalServiceBaseImpl
        • EventLocalServiceUtil
        • EventLocalServiceWrapper
      • Remote Service
        • EventService
        • EventServiceImpl(CLASS TO BE MANUALLY CHANGED)
        • EventServiceBaseImpl
        • EventServiceUtil
        • EventServiceWrapper
        • EventServiceSoap
        • EventSoap
      • Model
        • EventModel
        • EventModelImpl
        • Event
        • EventWrapper
  • You have to update core jsps for Document and Media portlet. Where will you do it.
  • You have to implement a solution involving lot of core JSP changes and a custom action what would you do.
    • I don’t remember the exact question. but if the question is intending to ask what to do if we have to override multiple JSPs. I think the answer is that the best approach is to have all the customization in one hook.
Some notes
– Generally overrides web resources found int portal-web – asp, jspf, javascript , css, images
– JSPF changes won’t take effect unless you modify the JSP that includes it
– CSS – you have to modify the css which includes it. just changing sub-css won’t work
– Portal Properties
— Model Listeners
— Validators
— Generators
— Content Sanitizers
– Override and define Struts actions
– Override portal services for e.g. MyUserLocalServiceImpl
– Language properties
– Search summaries, indexes and queries (index post processor)
– Servlet filter hooks – pre and post actions
Hooks are used to modify
– Portal Properties (Not all, only those listed in dtd)
– Language properties
– JSP files
– Index post processor
– Services
– Servlet filter
– Struts action
<!ELEMENT hook (portal-properties?, language-properties*, custom-jsp-dir?,
custom-jsp-global?, indexer-post-processor*, service*, servlet-filter*,
servlet-filter-mapping*, struts-action*)>
Steps for Application Display templates
  1. Create a *PortletDisplayHandler
  2. Register the hander in liferay-portlet.xml using <template-handler> tag
  3. Assign ADD_PORTLET_DISPLAY_TEMPLATE permissions in resource-actions/default.xml
  4. In your configuration JSP use <liferay-ui:ddm-template-selector> in the tag classNameId is what specifies your template
  5. Update view.jsp accordingly
Liferay Portlets Lifecycle
  1. void init(PortletConfig config) in GenericPortlet and init() in MVCPortlet
  2. void render(RenderRequest request, RenderResponse response)
  3. void processAction(ActionRequest request, ActionResponse response)
  4. void processEvent(EventRequest request, EventResponse response)
  5. void serveResource(ResourceRequest request, ResourceResponse response)
  6. void destroy()
GenericPortlet implements Portlet
LiferayPortlet extends GenericPortlet
MVCPortlet extends LiferayPortlet
Liferay Portlets Phases
  1. Render Phase (168)
  2. Action Phase(168)
  3. Event Phase(286)
  4. Resource Serving Phase(286)
Portlet Modes
  1. View
  2. Edit
  3. Help
Portlet Window States
  1. Normal
  2. Maximized
  3. Minimized
Services Injected by Service Builder
  1. counterService
  2. resourceService
  3. userService


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