Trying to display results from access database query on a JSP

Question

Seem to be having real difficulty with this one, i keep getting a null pointer exception :(. Wondered if anyone could point me to any examples of displaying the results on jsp. The database is connected, as i can display the query on netbeans, but just not on a jsp.

Answer 1

I think it would be good if we had a section in these forums for pre-canned answers to the same questions that come up again and again. It would save time.
Here is a rough outline for using JSP:
* Read a JSP book.
* The JSP page (View in MVC) should get all the data it needs to display from a useBean and/or request.getAttribute().
* The JSP page should not have any business logic. Its purpose is to display data only (and have some submit buttons such as 'update').
You can do some basic client side validation using javascript if you want. Because there is no business logic in it, you can easily debug
your code in the servlet or business logic. You can't set breakpoints in JSP and examine data easily.
* When you click the submit button, all data from <input type="text" tags, etc is put into request scope via name/value pairs.
* Submit the JSP page <form tag to a servlet (Control in MVC).
* The servlet reads the name/value pairs of data from the JSP page via request.getParameter()
* The servlet should then instansiate a business object (Model in MVC), passing the data it got from the page to the business logic.
Example: ProcessPage processPage();
if(request.getParameter("updateButtonClicked"))
processPage.updateData(data from the jsp page)
* The business logic should instansiate a separate database object (DAO) to get data to/from the database. Business logic should not have sql in it.
Business logic should not generate html. Business logic should not have request objects in it.
* The business logic should return data to the servlet that in turn will put it in request scope via request.setAttribute() so the JSP page can draw itself.
* The servlet should then call up the approprate JSP page.