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Unable to submit the form using while loop

This is my Code that retrieves information from database and displays it in Table with an addition button that will used to submit(add to fav) to another new table with that row values and id of the user Below code displaying all records correctly with in table and every row is wrapped inside a form with button so when i click on a Particular row button then Values of that row only should be passed to target page,But for each and every row only the first record values are passing...
<%pst = con.prepareStatement("select * from reg_faculty");
res = pst.executeQuery();
while(res.next()) {
String uname = res.getString(1);
String id = res.getString(2);
String branch = res.getString(5);
String subject = res.getString(4);
%>
<tr><td align="center"><b><%=uname%></b></td><td align="center"><b><%=branch%></b></td>
<td align="center"><b><%=subject%></b></td>
<input type="hidden" name="fac_id" value="<%=id%>">
<input type="hidden" name="std_id" value="<%=ht%>">
<input type="hidden" name="fac_name" value="<%=uname%>">
<td align="center"><img src="viewimagef.jsp?id=<%=id%>&type=<%="faculty"%> " alt="" width="100" height="60" /></td>
<td align="center"><input type="submit" value="Add"/></td>
</tr>
<%
}
%>
Target page where the selected row values should pass to database but for any row selected the first record values are passing
String std_id1=request.getParameter("std_id");
String fac_id2=request.getParameter("fac_id");
String name=request.getParameter("fac_name");
try{
pst=con.prepareStatement("select * from fav_faculty where std_id=? AND fac_id=?");
pst.setString(1, std_id1);
pst.setString(2, fac_id2);
res=pst.executeQuery();
boolean exists = false;
if(res.next()){
out.println("Faculty Already exist in your List");
out.println("Faculty: "+fac_id2+" Student Id: "+std_id1+" Name: "+name);
}else{
pst=con.prepareStatement("insert into fav_faculty values(?,?)");
pst.setString(1, std_id1);
pst.setString(2,fac_id2);
int j=pst.executeUpdate();
if(j>0){
out.println("You successfully added "+name+" to your Faculty List");
}
}
}catch (Exception e) {
out.println("Unable To Add");
}

the problem is in the submit buttons you are using, a submit button belongs to the whole form, a working scenario would be changing the value of the submit button to the faculty id but keeping the same name for all the submit buttons.
another and probably a better solution would be adding a checkbox instead of a submit buttons.
<tr><td align="center"><b><%=uname%></b></td><td align="center"><b><%=branch%></b></td>
<td align="center"><b><%=subject%></b></td>
<input type="hidden" name="fac_id" value="<%=id%>">
<input type="hidden" name="std_id" value="<%=ht%>">
<input type="hidden" name="fac_name" value="<%=uname%>">
<td align="center"><img src="viewimagef.jsp?id=<%=id%>&type=<%="faculty"%> " alt="" width="100" height="60" /></td>
<td align="center"><input type="ckeckbox" name="fac_id" value="<%=id%>">
</tr>
%><%-- end of the while loop --%>
<input type="submit" value="add all">
and in the target page
String allSelectedFacultyIds[]= request.getParameterValues("fac_id");
for (int i=0;i<allSelectedFacultyIds.length;i++)
{
pst=con.prepareStatement("select * from reg_faculty where id="+allSelectedFacultyIds[i]);
//now you have the name, id, ... so the rest of your code should apply with minor changes
}

Link to the correct item page by selecting the list of items in for loop

This is my jsp page that retrieve the list of items from database using for loop
<%
itemManager mgr = new itemManager();
Item[] items = mgr.getAllItems();
for(int i = 0; i < items.length; i++){
%>
<tr>
<td> <img border="0" src="<%=items[i].getItemImage() %>" width="100" height="100">
</td>
<td>
<%=items[i].getItemName()%>
<input type="text" name="itemID" value="<%=items[i].getItemID()%>">
<br/>
<%=items[i].getItemDesc()%>
<br/>
Start Bid : <%=items[i].getStartBid()%>
<br/>
Buy it now : <%=items[i].getEndBid()%>
<br/>
Bidding close on : <%=items[i].getDuration()%>
<br/>
<input type="submit" value="View">
<%
}
%></table>
This is the jsp page that link to the item you selected previously
<table border="1" align="center">
<%
itemManager mgr = new itemManager();
Item items = mgr.getItem((Integer)session.getAttribute("ITEM_DATA"));
%>
<tr>
<td> <b> <%=items.getItemName() %></b> </td>
</tr>
</table>
This is the servlet to store the session of the selected item id and forward to the correct item jsp page.
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
HttpSession session = request.getSession(true);
int id = Integer.parseInt(request.getParameter("itemID"));
session.setAttribute("ITEM_DATA",id);
RequestDispatcher rd = request.getRequestDispatcher("viewItem.jsp");
rd.forward(request, response);
}
However, after I clicked the view button. It keeps linking to the itemID = 1.
The URL dispalys "/ItemServlet?itemID=1&itemID=2" .
In fact, if I click on itemID=2 the URL should display like this:
"/ItemServlet?itemID=2"
As a result, how can I achieve this? Thanks in advance!

The problem in your code is you are using a single form and dynamically creating Input box inside the form. So all the input box will be having same name. That's why when you submit the form all the input box values are sent as request parameters. I just reduced some part in your code for better under standing. Take this as your code
<form action="item" method="get">
<table>
<%
ItemManager mgr = new ItemManager();
Item[] items = mgr.getAllItems();
for(int i = 0; i < items.length; i++){
%>
<tr>
<td>
<%=items[i].getItemName()%>
<input type="text" name="itemID" value="<%=items[i].getItemId()%>">
<input type="submit" value="View"> </td></tr>
<%
}
%></table>
</form>
When you run this code and if you check the rendered HTML code it will be look
<form action="item" method="get">
<table>
<tr><td>
aaa
<input type="text" name="itemID" value="1">
<input type="submit" value="View"> </td></tr>
<tr>
<td>
bbb
<input type="text" name="itemID" value="2">
<input type="submit" value="View"> </td></tr>
<tr><td>
ccc
<input type="text" name="itemID" value="3">
<input type="submit" value="View"> </td></tr>
</table>
</form>
Here All the Input box having same name as "itemID". As a solution you can create the form inside the for loop, so that while submitting only one Input box value will be sent as request.
Create form inside your for loop like below code.
<table>
<%
ItemManager mgr = new ItemManager();
Item[] items = mgr.getAllItems();
for(int i = 0; i < items.length; i++){
%>
<form action="item" method="get">
<tr>
<td>
<%=items[i].getItemName()%>
<input type="text" name="itemID" value="<%=items[i].getItemId()%>">
<input type="submit" value="View"> </td></tr>
</form>
<%
}
%></table>
Hope This will help you.

change the name of text field dynamically.
And use getQueryString() in servlet to find the itemId name and value. by using EL.I hope this will help you

how to break columns in a table using jdbc

I am making a simple table which stores product details from database using jdbc connection.
My table looks like this:
<table>
<td>
<img border="3"
src="image path" height="200" width="200" />
<p align="center"></p> // these tag contains specific product details from db
<p align="center"></p>
</td>
</table>
right now I'm getting each product details in particular column( i.e multiple column within single row), but my problem is that this row keeps on expanding , & I want this row(which consist of multiple columns) to automatically break let say after every 5 products.
In simple words i want to arrange my products details in 4 x n format just like in flipkart , as shown below:
http://www.flipkart.com/mobiles/android-phones~type/pr?sid=tyy,4io&otracker=hp_nmenu_sub_electronics_0_Android%20phones
you can see first product sony experia then lg then after samsung galaxy product, new row starts then again 4 products , then new row. In this way i need to show my products which are coming from database using jdbc connection.
Can anyone suggest me what's the best possible approach to achieve this. & Is there any option to break columns after 4th one & then start new row?
I am displaying database contents in jsp as shown below, just for demo:
<%
//1. Retrieve all products from database
//1a. Load the Driver
Class.forName("com.mysql.jdbc.Driver");
//1b. Get a connection to the database
Connection con = DriverManager.getConnection("url", "un", "pwd
PreparedStatement ps = con.prepareStatement("SELECT * FROM table");
//1d. Execute and retrieve our result
ResultSet rs = ps.executeQuery();
//2. Base on the results returned, construct a table
%>
</p>
<table border="0">
<%
if(rs.next()) {
rs.beforeFirst(); // for making sure you dont miss the first record.
while(rs.next())
{ // opening while loop brackets.
%>
<td>
<div style=""><img border="3"
src="<%=rs.getString("image") %>" height="200" width="200" /></div>
<p align="center"><%=rs.getString("title")%></p>
<p align="center"><%=rs.getString("price")%></p>
</td>
<%
} //closing while loop bracket
}
else {
//if no record is found, simply display a no record message
%>
Nothing.
<%
}
%>
</table>

Use <tr> tags to organize the table in rows. (That's what it stands for - *t*able *r*ow.)
Keep track of how many products (N) you've read from the database. If N is a multiple of 4 (n % 4 == 0), close the <tr> and start a new one.
So the result looks like:
<table>
<tr>
<td>...</td>
<td>...</td>
<td>...</td>
<td>...</td>
</tr>
<tr>
<td>...</td>
<td>...</td>
<td>...</td>
<td>...</td>
</tr>
</table>
UPDATE based on updated question:
Here's my tweak based on your code. I really do not advocate doing SQL calls (or really any non-presentation-layer code) from within a JSP, but that's a matter for a different question.
<%
//1. Retrieve all products from database
//1a. Load the Driver
Class.forName("com.mysql.jdbc.Driver");
//1b. Get a connection to the database
Connection con = DriverManager.getConnection("url", "un", "pwd
PreparedStatement ps = con.prepareStatement("SELECT * FROM table");
//1d. Execute and retrieve our result
ResultSet rs = ps.executeQuery();
//2. Base on the results returned, construct a table
%>
</p>
<table border="0">
<tr>
<%
int i = 0;
if(rs.next()) {
rs.beforeFirst(); // for making sure you dont miss the first record.
while(rs.next())
{ // opening while loop brackets.
%>
<td>
<div style=""><img border="3"
src="<%=rs.getString("image") %>" height="200" width="200" /></div>
<p align="center"><%=rs.getString("title")%></p>
<p align="center"><%=rs.getString("price")%></p>
</td>
<%
i++;
if ((i % 4) == 0) {
%>
</tr>
<%
}
if (!rs.isLast()) { // don't open a new row if this is the last result
%>
<tr>
<%
} // closing isLast check
%>
<%
} //closing while loop bracket
}
else {
//if no record is found, simply display a no record message
%>
Nothing.
<%
}
%>
</tr>
</table>
I don't really have the patience to correct the whitespacing here, and I haven't actually compiled this, but hopefully you get the gist.

Apart from the response from dcsohl, you can use a combination of <div> and <span> elements. A <div> element is a block element, that is, each <div> will be rendered in new line. <span> element is an inline element.
This should help you:
<div>
<span></span>
<span></span>
<span></span>
<span></span>
<span></span>
</div>
<div>
<span></span>
<span></span>
<span></span>
<span></span>
<span></span>
</div>
<div>
<span></span>
<span></span>
<span></span>
<span></span>
<span></span>
</div>

how to display value in dropdown list depending on another dropdownlist using jsp?

I'm tying to bind the value to dropdownlist i.e named as subtype which is depending on another dropdownlist i.e named as type. Please tell me how I can do that.. I have given I following code which implement for binding the dropdownlist depending on another dropdownlist.
`<table>
<tr>
<td>
<label id="type">Chosen category : </label>
</td>
<td>
<% String getType=request.getParameter("id");
out.println("<h4>"+getType+" <a href='post free ads.jsp'>Change the
category</a> </h4>");
%>
</td>
</tr>
<tr>
<td>
<label id="typeselect">Select type : </label>
</td>
<td>
<select name="type">
<option value="none">Select</option>
<%
Connection conn = NewClass.getOracleConnection();
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("Select distinct company from admin.all_stuff
where stuff_type='"+getType+"' ");
while(rs.next()){
%>
<option value="<%=rs.getString(1)%>"><%=rs.getString(1)%></option>
<%
}
%>
</select>
</td>
</tr>
<tr>
<td> <label id="subtypeselect">Select Subtype : </label></td>
<td>
<select name="subtype">
<option value="none">Select</option>
<%
try
{ %>
<% String typeselected = request.getParameter("type");
Statement stmtmt = conn.createStatement();
ResultSet rse = stmtmt.executeQuery("Select model_no from admin.all_stuff
where stuff_type='"+getType+"' and company='"+typeselected+"' ");
while(rse.next()){
%>
<option value="<%=rse.getString(1)%>"><%=rse.getString(1)%></option>
<%
}
%>
<% }
catch(Exception e)
{
out.println(e.getMessage());
}
%>
}
</select>
</td>
</tr>
</table>`

You need AJAX for this to get it work.
Your jsp is compiled into a servlet and then delivered to your client. After that no more changes are possible.
You have to handle an onChange event on the first drop down box in HTML and then post an AJAX request to your server to send back the content for the second drop down box.

Easiest way to start with AJAX is to get some library for example jQuery
$.get('ajax/test.html', function(data) {
alert(data);
});
This code allow us to download from HTML page some content from URL 'ajax/test.html'.
Second argument is callback function. Variable data has content of page 'ajax/test.html'
More: http://api.jquery.com/jQuery.get/

How can I check for gender value by NameID?

I have this code that checks duplicate name id
NameRefBean myNameBean = new NameRefBean();
myNameBean.load(NameID);
if (!myNameBean.getErrFlag()) {
errExistFlag = true;
errCode = DUPLICATE_NAME_ID;
return(false);
I have switch case where it saves data from the jsp page form
case ACTION_SAVE:
if (hdTxnType.equalsIgnoreCase("Add")) {
if (validateInputData()) {
nameBean.setNameID(tbNameID);
nameBean.setName(tbName);
nameBean.setGender(tbGender);
hdTxnType = new String("Update");
}
} else {
nameBean.setNameID(hdNameID);
nameBean.setName(tbName);
nameBean.setGender(tbGender);
}
break;
My question is how can I check for gender value when particular nameid is selected? If user changes gender value from M to F, I need to give a warning on the jsp page saying "gender already exist do you want to modify it?"
Here is my jsp page
<% if (nameBean.getErrFlag()) {%>
<CENTER><b><font color=red><%= nameBean.getErrMsg() %></b></font></CENTER>
<% } %>
<TABLE WIDTH="800" BORDER="0">
<TR>
<TD><B>Name ID: </B></TD>
<% if (nameBean.getTxnType().equalsIgnoreCase("Add"))
{ %>
<TD><INPUT TYPE=TEXT NAME="tbNameID" VALUE="<%= nameBean.getnameID()%>" ></TD>
<% } else { %>
<TD><%= nameBean.getNameID()%> </TD>
<% } %>
<TD><B> Name: </B></TD>
<TD><INPUT TYPE=TEXT NAME="tbName" VALUE="<%= nameBean.getName()%>" ></TD>
<TD><B>Gender: </B></TD>
<TD><INPUT TYPE=TEXT NAME="tbGender" VALUE="<%= nameBean.getGender()%>" ></TD>
</TR>
<BR>
<TR>
<% if (userProfileBean.hasRole("FULL") ) { %>
<TD>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Save Changes">
<% if (nameBean.getTxnType().equalsIgnoreCase("Update"))
{ %>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Delete">
<% } %>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Cancel">
</TD>
<% } %>

You could add a piece of JavaScript that print the warning, if a user changed the gender. The only thing you have to do then, is to enable this java script if the nameid is already set (then the name already exists, and every change should print the warning.) If the nameid is null, then it is a new name and you must not enable the java script warning functionality.