java servlet Null point exception
Question
I keep getting this a java.lang.null pointer exception, any help or suggestions would be much appreciated, I thought by putting in the if statement i would get rid of the errors so i have no idea what is wrong
StandardWrapperValve[UserManagementServlet]: Servlet.service() for
servlet UserManagementServlet threw exception
java.lang.NullPointerException
at com.bsapp.servlets.UserManagementServlet.processRequest(UserManagementServlet.java:40)
at com.bsapp.servlets.UserManagementServlet.doGet(UserManagementServlet.java:104)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
The jsp file is
</div>
<form action="<c:url value='/UserManagement?action=listConfirm'/>">
<!--<input type="text" name="action">-->
<button class ="btn btn-large" type ="submit">USERS</button>
</form>
</div>
and the servlet is
protected void processRequest(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
String action = request.getParameter("action");
if (action.equals("list")) {
doUserListing(request, response);
}
if (action.equals("add")) {
addNewUser(request, response);
} else{
out.println("<!DOCTYPE html>");
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet SearchServlet</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>Well Shit</h1>");
out.println("</body>");
out.println("</html>");
}
}
void doUserListing(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
UserDAO userDAO = new UserDAO();
Vector<User> allUsersVect = userDAO.getAllUsers();
request.getSession(true).setAttribute(IConstants.SESSION_KEY_ALL_USERS, allUsersVect);
RequestDispatcher rd = request.getRequestDispatcher("/user-listing.jsp");
rd.forward(request, response);
}
1 answers
solution1
2 2019-01-10 18:57:35
Firstly, you should provide what line is 40. The error is either that request or action is null as far as I can tell with the limited information you provided. Try adding
if (action == null)
return;
Make sure to replace return; with any error processing you need to execute.
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