NullPointerException with Servlet
- by RonaDona
I am calling a Servlet using its URL address. This is the URL I am typing
http://localhost:7001/ryan/olympics?action=selectCatalog&id=1
This is the Servlet's URL for sure; if I change the address I get
page not found
This is the code for the Servlet.
public class Servlet extends javax.servlet.http.HttpServlet
implements javax.servlet.Servlet {
private static final long serialVersionUID = 1L;
public Servlet() {
super();
}
public void init(ServletConfig config) throws ServletException {
System.out.println("*** initializing controller servlet.");
super.init(config);
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String action = request.getParameter("action");
if (action.equals("selectCatalog")) {
String categoryId = request.getParameter("id");
ProductModelDAO dao4 = new ProductModelDAOImpl("jpac");
if (categoryId != null && !categoryId.trim().equals("")) {
CategoryDAO dao1 = new CategoryDAOImpl("jpac");
try {
Category category = dao1.getCategoryName(categoryId);
request.setAttribute("category", category);
} catch (Exception e) {
e.printStackTrace();
}
}
try {
@SuppressWarnings("unchecked")
List<Product> products = dao4
.getProductsByCategory(categoryId);
request.setAttribute("products", products);
} catch (Exception e) {
e.printStackTrace();
}
url = "SelectCatalog.jsp";
RequestDispatcher requestDispatcher =
getServletContext().getRequestDispatcher(url);
requestDispatcher.forward(request, response);
I get the NullPointerException pointing to the RequestDispatcher's line. Any help?
