Redirect to another Portlet

This is a very short post, but big enough in its work.
The following code is capable of redirecting to some other portlet.


ThemeDisplay themeDisplay = (ThemeDisplay)liferayPortletRequest.getAttribute(WebKeys.THEME_DISPLAY);
String url =  themeDisplay.getPortalURL() + themeDisplay.getPathMain() + "/message_boards/find_message?messageId=" + _message.getMessageId();