This discussion board application is created using Liferay DXP. Liferay’s in built Message Board portlet has been customized to make the discussion board category specific.
In Liferay’s built-in Message Board portlet, all the categories are always visible to the user. It create two challenges
• The user permission management becomes somehow challenging when the administrator wants to create multiple categories in discussion board through a single interface. For example: If the admin wants to create a single technology related website that can display three separate discussion boards for Java, PHP and .Net, there is no possibility to limit the user access to particular page only.
• The same challenge is applicable to Search function as well. The administrator cannot control the display threads shown as search results
The customize discussion board offers much flexibility.
1) The administrator can choose the root category for the portlet instance. This root category selection possibility is a per-instance based setting.
Category Preference can be selected from configuration page of portlet. The user will be able to view the threads and sub categories of selected category only.
2) The administrator can set page wise category preferences simply by selecting respective root categories in both portlet instances. Therefore, multiple discussion boards can be handled from a single website or web portal.
The user will be able to access the threads and contents of only those categories which are allocated to the particular page.
3) This flexibility is applicable to Search function as well. The admin has already set categories, and the user will to access the threads and contents as per those categories.

Note: Once app is installed, App server will require to be restarted to app to fully function.