how to add these the items in a cart “jsp”

Question

I'm using the following code to display my data from a database but I'm unable to add data to the cart on event like when I click the "add to cart" button

query = "select * from books";
rs = st.executeQuery(query);
out.println("<h4><marquee> WELCOME TO BOOK SECTION </marquee></h4>");
out.println("<table border=1>");
count=1;
while (rs.next()) {
    i++;
    itemName = rs.getString("BOOK_NAME");
    avail = rs.getString("BOOK_AVAIL");
    cost = rs.getFloat("BOOK_sell_price");
    if(count==1){
        out.print("<tr>");
    }   
    out.println("<td>" + itemName  +  " "+  avail + "  " + cost + "<br>");
    out.println("<input type=button value='add to cart' onclick=addcart();>");
    out.print("</td>");
    count+=1;
    if(count>3){
        out.print("</tr>");
        count=1;
    }

Can anyone give an appropriate method to add these items in the backend so that when I go to cart.jsp I'll be able to find the item on cart for which I have clicked "add to cart"?

I don't know how to use session without manipulating t above code and if any other method available please let me know.

Thank you well in advance.

Answer 1

Just put each add button in its own <form> wherein you define the product ID as a hidden input field. You of course have a column representing the product ID in the DB table, do you?

<form action="add" method="post">
    <input type="hidden" name="id" value="${id}" />
    <input type="submit" value="Add to cart" />
</form>

This way the id is available as request parameter. No need for ugly Javascript hacks which would make your website unusable on websites with JS disabled.