Question

Hi i have a servlet which get a parameter form a jsp on a submit button. One of the parameters is reporting to be null though. However this is not the case. The text input in question is filled automatically by a session variable and is definitely not null and can be seen in the text box on the page. But when inside the servlet the java console indicates that the variable is null? below is the code that populates the box and reads the parameter.

 <input type="text" id="cID" value="<%= session.getAttribute("cID")%>" readonly="readonly"> 

reading the parameter:

String cID = request.getParameter("cID");

On printing cID to the console in netbeans it is reportedly null?

Answer 1

Add the name attribute to the input tag

<input type="text" id="cID" name="cID" value="<%= session.getAttribute("cID")%>" readonly="readonly">

It’s the name attribute, not the id attribute, that defines the name of the parameter that’s sent to the server. id is purely a client-side thing.