Unable to update database

[Loh Peggie]

Hey guys I am in a desperate need of help:(

<form id="updateForm" method="post" action="./EditProductsAdmin">--------------->Why is this always in error?

	  
			<%
				//Retrieve the id of the product selected by the user
				//the product id is sent via the URL as a parameter
				//String ItemCode; //= -1;
				String ProductId = request.getParameter("ProductId");
				if(ProductId != null) {
					//Convert from string to int
					//ItemCode = Integer.parseInt(strId);
				}
				
				//Load the database driver
		       	Class.forName("com.mysql.jdbc.Driver");
				//Create a connection to our database
		       	Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/feppz", "root", "");
				//create an SQL statement
		       	PreparedStatement ps = con.prepareStatement("SELECT * FROM products WHERE ProductId=?");
				//set the ID to be the id above
		       	 	ps.setInt(1, Integer.parseInt(request.getParameter("ProductId")));
				//Execute and retrieve our result
		       	ResultSet rs = ps.executeQuery();
			%>
        <%
        	//if there is a result, rs.next() will be true
        	//else it will be false
			if(rs.next()) {
		%>
				<form id="formH" class="form">
                <table width="90%" border="0">

		          <tr>
		            <td width="28%">Product Id</td>
		            <td width="72%"><input name="ProductId" type="text" id="ProductId" value="<%=rs.getInt("ProductId")%>" /></td>
		          </tr>
		          <tr>
		            <td>Product Name</td>
		            <td><input name="ProdName" type="text" id="ProdName" value="<%=rs.getString("ProdName")%>" /></td>
		          </tr>
		    		<tr>
		            <td>Product Color</td>
		            <td><input name="ProdColor" type="text" id="ProdColor" value="<%=rs.getString("ProdColor")%>" /></td>
		          </tr>
                             <tr>
		            <td>Descriptions</td>
		            <td><textarea name="ProdDesc" id="ProdDesc" cols="45" rows="5"><%=rs.getString("ProdDesc") %> </textarea></td>
		          </tr>

                       <tr>
		            <td>Unit Price</td>
		            <td><input name="UnitPrice" type="text" id="UnitPrice" value="<%=String.format("$%.2f",rs.getDouble("UnitPrice"))+"\t" %>" /></td>
		          </tr>

                   <tr>
		            <td>Quantity</td>
		            <td><input name="Quantity" type="text" id="Quantity" value="<%=rs.getString("Quantity")%>" /></td>
		          </tr>



		    
		            <tr>
		            <td>UserId</td>
		            <td><input name="UserId" type="text" id="UserId" value="<%=rs.getInt("UserId")%>" /></td>
		          </tr>
		          
	        </table>

		<%
			}
			else {
				//if no record is found, simply display a no record message
		%>
        		No record found.
        <%
			}
		 %>	

		 	<input type="submit" name="action" value="Update"/>
		 	<input type="submit" name="action" onclick="return confirm_delete()" value="Delete"/>	
	</form>	
	</form> 	

This is my servlet:

package sg.edu.nyp.feppz;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.util.Enumeration;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import sg.edu.nyp.feppz.user.User;



public class EditProductsAdmin extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
  
    public EditProductsAdmin() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

	/**
	 
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */



protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	
	//Retreive the user data from the session object
	User user = (User)request.getSession().getAttribute("USER_DATA");

	String action = request.getParameter("action");
	if("Update".equalsIgnoreCase(action) == true) {
		this.update(request, response);
	} else if("Delete".equalsIgnoreCase(action) == true) {
		this.delete(request, response);
	}
	
}

/**
 * @see HttpServlet#update(HttpServletRequest request, HttpServletResponse response)
 */

private void update(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	// TODO Auto-generated method stub
	
	String name = null;
	String value = null;
	
    // Get the values of all request parameters
	Enumeration paramNames = request.getParameterNames();
	while(paramNames.hasMoreElements()) {
        // Get the name of the request parameter
        name = (String)paramNames.nextElement();
        System.out.println(name);

        // Get the value of the request parameter
        value = request.getParameter(name);

        // If the request parameter can appear more than once in the query string, get all values
        String[] values = request.getParameterValues(name);

        for (int i=0; i<values.length; i++) {
        	System.out.println("    "+values[i]);
        }
    }		
	//retrieve the ProductId text from the form in the CreateProduct.jsp file
	if(request.getParameter("ProductId") == null || request.getParameter("ProductId").equals(""))
	{
		//if it is null => something is wrong, send the browser back to the
		//CreateProduct.jsp file
		request.setAttribute("ERROR_MESSAGE", "ProductId cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;
	}
	
	//	int ItemCode;
	//Limit the item code to be 4 digits only.
	//if(ItemCode >= 5 && ItemCode <0)
		//System.out.println("You have enter an invalid code");
	
	//retrieve the ItemName text from the form in the CreateProduct.jsp file
	if(request.getParameter("ProdName") == null || request.getParameter("ProdName").equals(""))
	{
		request.setAttribute("ERROR_MESSAGE", "Product Name cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;
	}
	
	//retrieve the Images from the CreateProduct.jsp file
//	if(request.getParameter("ProdCOlor") == null || request.getParameter("ProdColor").equals(""))
//	{
//		request.setAttribute("ERROR_MESSAGE", "Product Color cannot be empty");
//		RequestDispatcher rd = request.getRequestDispatcher("EditProductsAdmin(A).jsp");
//		rd.forward(request, response);
//		return;
//	}
	
	//retrieve category from the CreateProduct.jsp file
//	if(request.getParameter("ProdDesc") == null || request.getParameter("ProdDesc").equals(""))
//	{
//		request.setAttribute("ERROR_MESSAGE", "Product desc cannot be empty");
//		RequestDispatcher rd = request.getRequestDispatcher("EditProductsAdmin(A).jsp");
//	rd.forward(request, response);
//	return;
	
//}	
	
	
	//retrieve quantity from the CreateProduct.jsp file
	if(request.getParameter("UnitPrice") == null || request.getParameter("UnitPrice").equals(""))
	{
		request.setAttribute("ERROR_MESSAGE", "UnitPrice cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;

	}
	
	//retrieve descriptions from the CreateProduct.jsp file
	if(request.getParameter("Quantity") == null || request.getParameter("Quantity").equals(""))
	{
		request.setAttribute("ERROR_MESSAGE", "Quantity cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;
	}
	
	//retrieve cost from the CreateProduct.jsp file
	if(request.getParameter("ProdCatId") == null || request.getParameter("ProdCatId").equals(""))
	{
		request.setAttribute("ERROR_MESSAGE", "ProdCatId cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;

	}
	
          
	//retrieve cost from the CreateProduct.jsp file
	if(request.getParameter("UserId") == null || request.getParameter("UserId").equals(""))
	{
		request.setAttribute("ERROR_MESSAGE", "UserId cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;

	}


	//Connect to database
	try {
		//Ensure the the driver class is loaded.
		Class.forName("com.mysql.jdbc.Driver");
		//Create a connection to our database.
		//localhost = server name
		//feppz = database name
		//root = user name, password = empty
		Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/feppz", "root", "");
		//create an SQL statement, ? marks denote values that we will add later
		PreparedStatement ps = con.prepareStatement("UPDATE PRODUCTS SET ProdName=?, ProdColor=?,ProdDesc=?, UnitPrice=?, Quantity=?, ProdCatId=?, UserId=? WHERE ProductId=?");
		//replace first ? mark with values from the ItemCode text box
		ps.setString(1, request.getParameter("ProdName"));
		ps.setString(2, request.getParameter("ProdColor"));
		ps.setString(3, request.getParameter("ProdDesc"));
		ps.setFloat(4, Float.parseFloat(request.getParameter("UnitPrice")));
		ps.setString(5, request.getParameter("Quantity"));
		ps.setInt(6, Integer.parseInt(request.getParameter("ProdCatId")));
		ps.setInt(7, Integer.parseInt(request.getParameter("UserId")));
		//execute to insert into the database
		ps.executeUpdate();
		//close connection
		con.close();
		//redirect user to UpdateProductSuccessful.jsp page
		response.sendRedirect("Home.jsp");
		
	} catch (Exception e) {
		e.printStackTrace();
		return;
	}
	
}


/**
 * @see HttpServlet#delete(HttpServletRequest request, HttpServletResponse response)
 */
private void delete(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	// TODO Auto-generated method stub
	//retrieve the ItemCode text from the form in the CreateProduct.jsp file
	if(request.getParameter("PorductId") == null || request.getParameter("ProductId").equals(""))
	{
		//if it is null => something is wrong, send the browser back to the
		//CreateProduct.jsp file
		request.setAttribute("ERROR_MESSAGE", "Product Id cannot be empty");
		RequestDispatcher rd = request.getRequestDispatcher("trial.jsp");
		rd.forward(request, response);
		return;
	}

	//Connect to database
	try {
		//Ensure the the driver class is loaded.
		Class.forName("com.mysql.jdbc.Driver");
		//Create a connection to our database.
		//localhost = server name
		//feppz = database name
		//root = user name, password = empty
		Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/feppz", "root", "");
		//create an SQL statement, ? marks denote values that we will add later
		PreparedStatement ps = con.prepareStatement("DELETE FROM products WHERE ProductId=?");
		//replace first ? mark with values from the ItemCode text box
		ps.setInt(1, Integer.parseInt(request.getParameter("ProductId")));

		//execute to insert into the database
		ps.executeUpdate();
		//close connection
		con.close();
		//redirect user to UpdateProductSuccessful.jsp page
		response.sendRedirect("Home.jsp");
		
	} catch (Exception e) {
		e.printStackTrace();
		return;
	}

}

}

Really appreciate your help:D

[Himanshu Kansal]

Did you forget to write what help you need?

[Bear Bibeault]

Please be sure to take the time to compose descriptive subjects for your posts; read this for more information.

A title such as "Urgently need help" is not helpful. What would happen if all posts had such a title?

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[Loh Peggie]

I am sorry:(

[Vijitha Kumara]

What is the issue you are having with this code ? Any error ?

[Loh Peggie]

Hey when I debug it shows no record:(

[Himanshu Kansal]

so what do you get exactly that can help us? any exceptions? logs? something?
Please triage your code and zero in on the fragment that you think is giving you problems. That would help us too in helping you.

Regards

[Jeanne Boyarsky]

This looks like the same problem as your other thread. Please continue discussion there so we aren't repeating the same questions. I had suggested a couple things to try. If they didn't work, you could post what happened when you tried.