Add Update problem in Hashtable

[sumit sharmast]

Dear All,

I am getting the following error in the SERVLET CODE. Please help.

ERROR MESSAGE:

HTTP Status 500 -

--------------------------------------------------------------------------------

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Servlet execution threw an exception


root cause

java.lang.Error: Unresolved compilation problems:
The method addItem(String, LineItem) in the type Cart is not applicable for the arguments (LineItem)
The method removeItem(String, LineItem) in the type Cart is not applicable for the arguments (LineItem)

music.cart.DisplayCartServlet.doPost(DisplayCartServlet.java:87)
music.cart.DisplayCartServlet.doGet(DisplayCartServlet.java:114)
javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)


note The full stack trace of the root cause is available in the Apache Tomcat/6.0.20 logs.

Apache Tomcat/6.0.20
--------------------------------------------------------------------------------

LineItem.Java Code

import java.text.NumberFormat;
import java.io.Serializable;
import java.text.*;
import java.util.*;
import java.io.Serializable;

public class LineItem implements Serializable
{
	private String description;
    private double price;
    private int count;
    private int quantity;
    private int totalQuantity;
	private String code;
    
	public String getCode() {
		return code;
	}
	public void setCode(String code) {
		this.code = code;
	}
	public String getDescription() {
		return description;
	}
	public void setDescription(String description) {
		this.description = description;
	}
	public double getPrice() {
		return price;
	}
	public void setPrice(double price) {
		this.price = price;
	}
	public int getCount() {
		return count;
	}
	public void setCount(int count) {
		this.count = count;
	}
	public int getQuantity() {
		return quantity;
	}
	public void setQuantity(int quantity) {
		this.quantity = quantity;
	}
	public int getTotalQuantity() {
		return totalQuantity;
	}
	public void setTotalQuantity(int totalQuantity) {
		this.totalQuantity = totalQuantity;
	}
	public double getTotal()
    { 
        double total = price * quantity;
        return total;
    }
	
	 public String getPriceCurrencyFormat()
	    {
	       

	NumberFormat nf = NumberFormat.getCurrencyInstance(Locale.ENGLISH);

	String formattedValue = nf.format(price);

	return(formattedValue);

	    }
	
	 public String getImageURL()
	    {
	        String imageURL = "/booksShop/images/" + code + ".jpg";
	        return imageURL;
	    }}

Cart.Java Code

    import java.util.*;  
    import java.io.Serializable;  
      
      
    public class Cart implements Serializable  
    {  
             
            private Hashtable<String,LineItem>items;  
              
            public Cart()  
            {  
              
            items = new Hashtable<String,LineItem>();  
            }  
           
             
            public void setItems(Hashtable<String,LineItem> LineItems)  
            {  
                items=LineItems;  
                  
            }  
      
           
            public Hashtable<String,LineItem> getItems()  
            {  
                return items;  
                  
            }  
            public int getCount()  
            {   
                return items.size();  
            }  
          
        public void addItem(String id,LineItem h)  
        {  
              
            for (int i = 0; i<items.size(); i++)  
            {  
               LineItem lineItem = items.get(i);  
                 
       if (lineItem.getCode().equals(h.getCode()))  
                {  
             
          lineItem.setQuantity(h.getQuantity());  
                    return;  
                      
                }  
            }  
          
            items.put(id, h);  
        }  
          
       
          
        public void removeItem(String id,LineItem j)  
        {  
              
            for (int i = 0; i><items.size(); i++)  
            {  
               
                if(items.containsKey(id))  
                      
                    items.remove(items);  
                  
                  
                  
            }  
        }  
    }  

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

SERVLET CODE:

   
     import java.io.*;  
    import java.sql.Connection;  
    import java.sql.PreparedStatement;  
    import java.sql.ResultSet;  
    import java.util.ArrayList;  
    import java.util.Hashtable;  
      
    import javax.servlet.*;  
    import javax.servlet.http.*;  
      
    import music.business.*;  
    import music.data.*;  
      
    public class DisplayCartServlet extends HttpServlet  
    {  
        public void doPost(HttpServletRequest request,  
                HttpServletResponse response)  
                throws IOException, ServletException  
        {  
            String x = request.getParameter("quantity");  
            String y = request.getParameter("productCode");  
            String z = request.getParameter("removeButton");  
            String ub = request.getParameter("updateButton");  
              
     HttpSession session = request.getSession();  
              
    Cart k = (Cart) session.getAttribute("cart");   
      
      
      
    if (k == null)  
    {  
    k = new Cart();  
    session.setAttribute("cart", k);  
    }  
      
              
           int quantity;  
           try  
             {  
              quantity = Integer.parseInt(x);  
                
            }  
            catch(NumberFormatException nfe)  
            {  
              quantity = 1;  
            }  
             
            Hashtable><String,LineItem>items=k.getItems();  
              for (int i = 0; i<items.size(); i++)  
            {  
              LineItem v = items.get(i);  
              if(v.getCode().equals(y) && ub==null && quantity>0)  
                quantity = v.getQuantity()+ 1;  
               }  
          if (z != null)  
            {  
      
                quantity = 0;  
            }  
      
             
            LineItem  d = DAO.selectProduct(y);  
            
            session.setAttribute("product", d);  
      {  
                LineItem t = new LineItem();  
             t.setCode(d.getCode());  
             t.setDescription(d.getDescription());  
                t.setPrice(d.getPrice());  
                  
                t.setQuantity(quantity);  
                if (quantity > 0)  
 k.addItem(t);//Error is here,What will be the correct argument inside the addItem method, in place of addItem(t) ??? 
                  
                else if (quantity == 0)  
 k.removeItem(t);//Error is here,What will be the correct argument inside the addItem method, in place of addItem(t) ??? 
            }  
            session.setAttribute("cart", k);  
              
              
            String url = "";  
            if (k.getItems().size() <= 0)  
            {  
                url = "/cart/quick_order.jsp";  
            }  
            else  
            {  
                url = "/cart/cart.jsp";  
            }  
      
            RequestDispatcher dispatcher =  
                    getServletContext().getRequestDispatcher(url);  
            dispatcher.forward(request, response);  
        }  
          
        public void doGet(HttpServletRequest request,  
                HttpServletResponse response)  
                throws IOException, ServletException  
        {  
            doPost(request, response);  
        }  
    }  

-----------------------------------------------------------------------------------


JDBC CODE:

            

public static ArrayList< LineItem > selectJavaProducts()  
            {  
                ConnectionPool pool = ConnectionPool.getInstance();  
                Connection connection = pool.getConnection();  
                PreparedStatement ps = null;  
                ResultSet rs = null;  
                String query = "SELECT * FROM Product where category='java'";  
                try  
                {  
                    ps = connection.prepareStatement(query);  
                    rs = ps.executeQuery();  
                    ArrayList<LineItem> products = new ArrayList<LineItem>();  
                    while (rs.next())  
                    {  
                         LineItem  p = new  LineItem ();  
                       
                          
                        p.setCode(rs.getString("ProductCode"));  
                        p.setDescription(rs.getString("ProductDescription"));  
                        p.setPrice(rs.getDouble("ProductPrice"));  
                         
                        products.add(p);  
                    }  
                     
                       
                    return products;  
                }  
                catch(SQLException e)  
                {  
                    e.printStackTrace();  
                    return null;  
                }  
                finally  
                {  
                    try  
                    {  
                        if (rs != null)  
                            rs.close();  
                    }   
                    catch(SQLException e)  
                    {  
                        e.printStackTrace();  
                    }  
                    try  
                    {  
                        if (ps != null)  
                            ps.close();  
                    }   
                    catch(SQLException e)  
                    {  
                        e.printStackTrace();  
                    }  
                    pool.freeConnection(connection);  
                }  
            }  

[sumit sharmast]

Thank you sir for your suggestion.

[Seetharaman Venkatasamy]

From your post:

root cause

java.lang.Error: Unresolved compilation problems:
The method addItem(String, LineItem) in the type Cart is not applicable for the arguments (LineItem)
The method removeItem(String, LineItem) in the type Cart is not applicable for the arguments (LineItem)

your Cart.java has addItem(String, LineItem) ,
but you try to inkove with single argument as addItem(t). it is same with removeItem.

[sumit sharmast]

Dear Mr. Seetharaman,

Thank you for your reply. What will be the correct argument inside the addItem method in the Servlet code, in place of addItem(t) ???

Can you correct it please. I would be very thankful.

Regards,

Sumit.