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Interfaces and utility classes
org.jasig.portal.portlet.servant.IPortletServantLocator provides two simple methods for obtaining servant instance by the client servant. locate() method can be used to obtain an existing instance, and create() method to create a new one.
The IPortletServant interface contains methods which client portlet can use to operate on the serant portlet. Most important ones being getRenderContent() and isComplete():
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public interface IPortletServant {
/**
* Returns the servant ID given by the portlet servant locator.
* @return a <code>String</code> value
*/
public String getId();
/** Allows the Client Portlet to ascertain if the Servant has accomplished the requested task
* (Note that the way which a certain task is requested is not specified by this interface;
* normally it will be documented by a particular IPortletServant and require some particular
* configuration paramaters used to initialize the servant)
* @return boolean value
*/
public boolean isComplete(PortletRequest request);
/**
* Obtain servant shared attribute
* @param request current portlet request
* @param key attribute key
* @return attribute value
*/
public Object getAttribute(PortletRequest request, String key);
/**
* Set servant shared attribute. The attribute will be accessible by the servant portlet
* through {@link ServantUtil}
* @param request current portlet request
* @param key attribute key
* @param value attribute value
*/
public void setAttribute(PortletRequest request, String key, Object value);
/**
* Render servant portlet into the current response.
* Note: as this method renders directly to the response output stream, it is recommended
* to use getRenderContent method instead (see below), and incorporate portlet content into
* the overall portlet rendering manually.
* @param request current portlet request
* @param response current portlet reponse
* @throws PortletException
* @throws IOException
*/
public void render(RenderRequest request, RenderResponse response) throws PortletException, IOException;
/**
* Initiate action processing on the servant portlet.
* Note: the use of this method is not recommended. Servant portlet would normally process the portlet action requests
* through the usual means (i.e. if an action request for the servant portlet comes in with the incoming HttpServletRequest).
* Calling this method (during client portlet action or render request processing) goes against JSR168 spec (but technically, works).
* @param actionRequestParameterMap
* @param request
* @param response
*/
public void processAction(Map actionRequestParameterMap, ActionRequest request, ActionResponse response);
/**
* Obtain content of the servant portlet for the current request.
* @param request current portlet render request
* @return content of the servant portlet
*/
public IPortletRenderContent getRenderContent(RenderRequest request, RenderResponse response);
}
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The servant portlet can use of the ServantUtil class to obtain information and communicate with the client portlet. Here are the important methodsmethod signatures:
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public static boolean isServantMode(PortletRequest request) /**public static String getClientId(PortletRequest request) public static *boolean Obtail client id for the servant isClientInitiatedServantActionRequest(HttpServletRequest request) public static void setAttribute(PortletRequest request, String key, Object value) public static Object getAttribute(PortletRequest request, String getClientId key) public static void setServantDone(PortletRequest request) |
Sample usage
An example of servant usage is given in PortletManagers' CategoriesWizardPage. Here are the important lines:
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IPortletServantLocator servantLocator = ServantLocatorAccessor.getPortletServantLocator(context);
IPortletServant servant = servantLocator.locate(this.groupsServantFunctionalName, request,true);
if (servant.isComplete(request)) {
IGroupMember[] categoryGroups = (IGroupMember[]) servant.getAttribute(request,"servantResult");
// switch to to the next screen
}
PortletSession session = request.getPortletSession();
IGroupMember[] categoryGroups = (IGroupMember[])session.getAttribute(PortletDefinitionWizard.PARAM_CATEGORY_GROUPS);
servant.setAttribute(request, "groupMembers", categoryGroups);
servant.setAttribute(request,"allowEntitySelect",false);
servant.render(request, response);
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