Various jsp rendering in Liferay

Question

I need to do the following construction:

String pageName = request.getParameter("pageName");
if ("some_parameter".equals("pageName")) {
    include("html/one.jsp", request, response);
}
if ("third_parameter".equals("pageName")) {
    include("html/two.jsp", request, response);
}

But I always have problems like NullPointerException.

I mean, I'm trying to make different renderURL show different jsps, but I don't know how to do this. If you do not explain what I am, but I have knowledge in this topic, write smth in the comments, I will give more information. Thanks in advance!

---

Ok, I give you my example:

public static final String VIEW = "view";                           //view.jsp parameter
public static final String ADD_BOOK = "add_book";                   //add_book.jsp parameter

private final String VIEW_PAGE_PATH = "/html/view.jsp";             //view.jsp path parameter
private final String ADD_BOOK_PAGE_PATH = "/html/add_book.jsp";     //add_book.jsp path parameter

@Override
public void render(RenderRequest request, RenderResponse response)
        throws PortletException, IOException {

    String pageName = request.getParameter("pageName");
    if (pageName.equalsIgnoreCase(ADD_BOOK)) {              
        include(ADD_BOOK_PAGE_PATH, request, response);
    } else {
        include(VIEW_PAGE_PATH, request, response);
    }
}

and my view.jsp:

<portlet:renderURL var="addBookVar">
    <portlet:param name="pageName" value="<%=Library.ADD_BOOK %>"/>
</portlet:renderURL>

<a href="${addBookVar}">Add Book</a>

Why is this code not working? What to do to achieve a situation when different renderURL show different jsps?

Answer 1

, " null". StringUtils.isNotEmpty(..) ref " , " .

Answer 2

.

:

String pageName = request.getParameter("pageName");
if (pageName.equals("some_parameter")) {
   include("html/one.jsp", request, response);
}
if (pageName.equals("third_parameter")) {
   include("html/two.jsp", request, response);
}

Answer 3

, , NullPointerException. , , , , null. , .

Answer 4

getPortletContext().getRequestDispatcher(ADD_BOOK_PAGE_PATH).include(request,response) include(ADD_BOOK_PAGE_PATH, request, response)