Portlet Preferences

The portlet specification mandates that portlet container provide persistent store for portlet preferences. Portlets can only access their preferences during requests (render or action). Portlet preferences are encapsulated by the PortletPreferences interface.

Portlets can update their preferences within the processing of the processAction() method. An exception is thrown if the portlet attempts to update preferences during a render request.

User preferences are stored and accessed through a PortletPreferences object. A handle to this object can be obtained by using both RenderRequest.getPreferences() and ActionRequest.getPreferences(), depending from which method the attempt to access the preferences is made. An individual preferences is called using getValue() or getValues(), for single string value or multiple string values respectively. The methods setValue() and setValues() modifies the preference, but no changes are stored in the datastore until the method store() is called. All user preferences must be defined in the portlet deployment descriptor.

Preferences defined at the organization will affect the user’s preference only if the user’s preference has not been defined and only until the user modifies the individual preference. Once preferences have been modified, it will retain its value, even if blank, until the reset() method is called on the preference.

LDAP attributes can only be accessed through the portlet implementation of a user info Map. All attributes needed within the portlet must be defined in the portlet deployment descriptor. The attribute map of all such defined attributes can be retrieved using either ActionRequest.getAttribute(PortletRequest.USER_INFO) or RenderRequest.getAttribute(PortletRequest.USER_INFO). Each attribute can then be retrieved using Map.get("Attribute Name").

Only user attributes defined in the deployment descriptor can be read. The user info map returned is unmodifiable.