How can I get current group id (or community id) in liferay (java)?

Question

I'm developing portlet with Vaadin in Liferay 6 and I need to get the ID of the community where the portlet is located. How is it done?

Solution

There is no Community entity in Liferay, it's just another kind of group (see GroupConstants)

If you have access to a ThemeDisplay object I think this will give you the Id of the community

long id = themeDisplay.getLayout().getGroupId();

In a struts action you can get ThemeDisplay like this:

ThemeDisplay themeDisplay = 
     (ThemeDisplay)request.getAttribute(WebKeys.THEME_DISPLAY);

where request can be a RenderRequest or an ActionRequest.