Why do I get an error "The method <method name>(String) is undefined for the type __2F_<webapp name>_2F_src_2F_main_2F_webapp_2F_index_2E_jsp"?

I’ve build a method which takes strings as input parameter. In my index.jsp page, I retrieve a GET-variable from the URL using request.getParameter(). Now, I want to call the aforementioned method on this string, but I get a compiler error saying “The method (String) is undefined for the type __2F__2F_src_2F_main_2F_webapp_2F_index_2E_jsp”. Does anyone know why I get this error and how I can get rid of it. Any help is greatly appreciated!
My code is rather lengthy, but I think this is relevant code:

categorie = request.getParameter("categorie");

if (categorie.equals("")) {
    categorie = "Category;";

ArrayList<String> categorieen = queryCategories(categorie);

Source: jsp

Leave a Reply