getAttribute causing a ClassCastException why? - servlets

Question

I can't figure out why I am getting this Exception everywhere I look says its because you are trying to cast a String to a ItemRating however from what I see in the code it is of object ItemRating. The error is given in the JSP page.
Servlet:
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package my.pack;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
*
* #author Lee Howon
*/
#WebServlet(name = "ProfileController", urlPatterns = {"/ProfileController"})
public class ProfileController extends HttpServlet {
/**
* Processes requests for both HTTP <code>GET</code> and <code>POST</code>
* methods.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
UserDB users = new UserDB();
String action =request.getParameter("action");
HttpSession session = request.getSession();
itemBean item = new itemBean();
ItemRating rating = new ItemRating(item,"0","false");
UserProfile profile = new UserProfile( users.getUsers().get(0).getUserID());
collection coll = new collection();
String itemCode = request.getParameter("itemCode");
if(session.getAttribute("theUser")==null){
User user = new User();
List<User> userList = users.getUsers();
user.setUserID(userList.get(0).getUserID());
user.setFirstName(userList.get(0).getFirstName());
user.setLastName(userList.get(0).getLastName());
user.setEmail(userList.get(0).getEmail());
user.setAddr(userList.get(0).getAddr());
user.setCity(userList.get(0).getCity());
user.setState(userList.get(0).getState());
user.setPostCode(userList.get(0).getPostCode());
request.setAttribute("theUser", user);
session.setAttribute("theUser", user);
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
else{
if(action.equals("save"))
{
List<itemBean> songs= coll.getItems();
for(int i = 0; i < songs.size(); i++){
if(itemCode.equals(songs.get(i).getItemCode()))
{
item.setItemCode(songs.get(i).getItemCode());
item.setSong(songs.get(i).getSong());
item.setArtist(songs.get(i).getArtist());
item.setCategory(songs.get(i).getCategory());
item.setSongURL(songs.get(i).getSongURL());
item.setRating(songs.get(i).getRating());
item.setDesc(songs.get(i).getDesc());
//request.setAttribute("itemBean", item);
}
}
profile.addItem(rating);
session.setAttribute("currentProfile", rating);
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
else if(action.equals("updateProfile")){
String[] itemList =request.getParameterValues("itemList");
for(String list: itemList){
for(int i=0; i<itemList.length; i++){
if(!coll.getItems().get(i).getItemCode().contains(list)){
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
else {
request.setAttribute("theItem", rating);
getServletContext().getRequestDispatcher("/CatalogController?action=coll.getItems.get(i).getItemCode()").forward(request, response);
}
}
}
}
else if(action.equals("updateRating")){
String[] checkRating= request.getParameterValues("itemList");
String itemRating = request.getParameter("rating");
itemBean currItem = null;
for(String list: checkRating){
for(int i=0; i<coll.getItems().size(); i++){
if(list.equals(coll.getItems().get(i).getItemCode())){
currItem = coll.getItems().get(i);
if(currItem == null){
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
else if(itemRating.equals("")){
currItem.setRating("");
} else if(currItem.getRating().equals(itemRating)){
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}else if(!currItem.getRating().equals(itemRating)){
currItem.setRating(itemRating);
}else{
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
}
}
}
session.setAttribute("currentProfile", itemRating);
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
else if(action.equals("updateFlag")){
}
else if(action.equals("signout")){
}
else{
//getServletContext().getRequestDispatcher("/profile.jsp)").forward(request, response);
}
}
//else{
// getServletContext().getRequestDispatcher("/profile.jsp").forward(request,response);
//}
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
*
* #param request servlet request
* #param response servlet response
* #throws ServletException if a servlet-specific error occurs
* #throws IOException if an I/O error occurs
*/
#Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
*
* #return a String containing servlet description
*/
#Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
JSP Page:
<%--
Document : bookmark
Created on : Feb 11, 2018, 1:41:26 PM
Author : Anastasia
--%>
<%#page import="my.pack.ItemRating"%>
<%#page import="my.pack.itemBean"%>
<%#page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<%#page import="my.pack.collection" %>
<%#include file="/header.jsp"%>
<%#include file="/user-navigation.jsp"%>
<%#include file="/site-navigation.jsp"%>
<div id="productList"><form action="ProfileController" method="post">
<table>
<%
//get the user bean from the request
***error here*** ItemRating itemRating = (ItemRating) session.getAttribute("currentProfile");
collection coll = (collection) session.getAttribute("itemList");
itemBean itemBean = new itemBean();
//String string = itemRating.getItem().getSong();
%>
<tr>
<th>Song Name</th>
<th>Category</th>
<th> My Rating</th>
<th> Update</th>
</tr>
<% if(session.getAttribute("currentProfile") != null )
for(int row=1; row <=1; row++) { %>
<tr>
<td><%= itemRating.getItem().getSong() %></td>
<td><%= itemRating.getItem().getCategory() %>}</td>
<td><%= itemRating.getItem().getRating() %></td>
<td><form action="ProfileController?action=updateProfile" method="post"><button type="submit" name="RateIt">
Rate</button><button type="submit" name="Update" action="ProfileController?action=itemList">
Update</button></form></td>
</tr>
<% } %>
</table>
</form>
<form action="ProfileController?action=updateProfile" method="post">
<input type="hidden" name="itemList" value="itemCode">
<input type="text" name="OST1" value="<%= itemBean.getRating() %>">
<input type="hidden" name="itemList" value="OST2">
<input type="text" name="OST2" value="<%= itemBean.getRating() %>">
<input type="hidden" name="itemList" value="OST3">
<input type="text" name="OST3" value="<%= itemBean.getRating() %>">
<input type="hidden" name="itemList" value="S1">
<input type="text" name="S1" value="<%= itemBean.getRating() %>">
<input type="hidden" name="itemList" value="S2">
<input type="text" name="S2" value="<%= itemBean.getRating() %>">
<input type="hidden" name="itemList" value="S3">
<input type="text" name="S3 " value="<%= itemBean.getRating() %>">
<button type="submit"> Update </button>
</form
<form action="ProfileController?action=deleteItem" method="POST">
<button type="button"> Delete </button>
</form>
</div>
<%#include file="/footer.jsp" %>

Answer 1

Looked into the code and looks like there is problem. Your flow is going to action "updateRating" where you are saving "currentProfile" named attribute having string value. Whereas in another scenario if your action is "save" then you are saving the correct object as attribute value.
Here is the correct code where you are saving the desired attribute object:
if(action.equals("save"))
{
List<itemBean> songs= coll.getItems();
for(int i = 0; i < songs.size(); i++){
if(itemCode.equals(songs.get(i).getItemCode()))
{
item.setItemCode(songs.get(i).getItemCode());
item.setSong(songs.get(i).getSong());
item.setArtist(songs.get(i).getArtist());
item.setCategory(songs.get(i).getCategory());
item.setSongURL(songs.get(i).getSongURL());
item.setRating(songs.get(i).getRating());
item.setDesc(songs.get(i).getDesc());
//request.setAttribute("itemBean", item);
}
}
profile.addItem(rating);
session.setAttribute("currentProfile", rating);
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
And here is the code where you are saving string value in the attribute which is causing the problem:
else if(action.equals("updateRating")){
String[] checkRating= request.getParameterValues("itemList");
String itemRating = request.getParameter("rating");
itemBean currItem = null;
for(String list: checkRating){
for(int i=0; i<coll.getItems().size(); i++){
if(list.equals(coll.getItems().get(i).getItemCode())){
currItem = coll.getItems().get(i);
if(currItem == null){
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
else if(itemRating.equals("")){
currItem.setRating("");
} else if(currItem.getRating().equals(itemRating)){
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}else if(!currItem.getRating().equals(itemRating)){
currItem.setRating(itemRating);
}else{
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}
}
}
}
session.setAttribute("currentProfile", itemRating);
getServletContext().getRequestDispatcher("/bookmark.jsp").forward(request,response);
}