Struts action JSP Arraylist

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1

Hi, What do i need to display an arralist of items in a JSP? I know about the JSTL tags. The doubt i have is whether i should add a get arraylist in the actionform?

From my EJB i receive an arraylist. Then action calls it, and JSP displays it.
Ot i just call the variable arraylist in the jsp and iterate using tags?

Thanks in advance

//Struts action.
 public ActionForward execute(ActionMapping mapping, ActionForm  form,
            HttpServletRequest request, HttpServletResponse response)
            throws Exception {

        BookingLineActionForm bookinglineform = (BookingLineActionForm) form; // get the form bean
         Bookingline bookingline = new Bookingline();
        //ArrayList mylist = new ArrayList();

        String placefrom = bookinglineform.getBkLPlaceFrom();
        String placeto = bookinglineform.getBkLPlaceTo();


        bookingline = lookupBookinglineFacade().tripSearch(placefrom,placeto);
        //BeanUtils.copyProperties(bookinglineform,bookingline);


//EJB
 public ArrayList findTrip(String placefrom, String placeto) {
       ArrayList q = null;
        try {

       q = (ArrayList) em.createQuery("SELECT c FROM Bookingline c WHERE" +
                "c.bkLPlaceFrom = :sessionName AND c.bkLPlaceTo " +
                "= :sessionName2").setParameter("sessionName",placefrom)
                .setParameter("sessionName2",placeto)
                .getResultList();

         } catch (NoResultException en) {
            // en.printStackTrace();
            return q = null;
        }

        return q;
    }

     public ArrayList tripSearch(String placefrom, String placeto) {
         ArrayList q = findTrip(placefrom,placeto);

         return q;
     }
2

Found answer, you do not need to use actionform.

You use request.setattribute in actionform and then use JSTL or Struts tags to iterate over list in JSP.

3

The struts framework automaticallty takes care of this for you :slight_smile: which is the beauty of being able to develop sites in java :slight_smile:

4

Hi,

What do u mean,
I am getting an error and cannot figure out if the problem is in the struts or EJB.

What is happening is that an empty rectangle is displayed in the jsp. And i don’t know if the error is in jsp, struts action or ejb.

-----------JSP-----------------

 <table border="1">
        <c:forEach var="bookinglist" items="${requestScope.bookingList}" >
        <tr>
    <td><c:out value="${bookinglist.bkLNo}"/></td>
    <td><c:out value="${bookinglist.BkLTransType}"/></td>
    <td><c:out value="${bookinglist.BkLCost}"/></td>
    <td><c:out value="${bookinglist.BkLArrival}"/></td>
    <td><c:out value="${bookinglist.BkLDepart}"/></td>
    <td><c:out value="${bookinglist.BkLPlaceTo}"/></td>
    <td><c:out value="${bookinglist.BkLDepartDay}"/></td>
    <td><c:out value="${bookinglist.BkLPlaceFrom}"/></td>
    <td><c:out value="${bookinglist.BkLTCNo}"/></td>
  </tr>

  </c:forEach>
    </table>

Struts Action

 BookingLineActionForm bookinglineform = (BookingLineActionForm) form; // get the form bean
        Bookingline bookingline = new Bookingline();
        //ArrayList mylist = new ArrayList();

        String placefrom = bookinglineform.getBkLPlaceFrom();
        String placeto = bookinglineform.getBkLPlaceTo();


        bookingline = lookupBookinglineFacade().tripSearch(placefrom,placeto);
        //BeanUtils.copyProperties(bookinglineform,bookingline);

        request.setAttribute("bookingList", bookingline);
5

Not sure if this may help, but when i click on view source in the jsp, after getting the result, this is displayed.

<table border=“1”>
<c:forEach var=“bookinglist” items=“” >
<tr>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
<td><c:out value=“”/></td>
</tr>

</c:forEach>
</table>

6

are you missing the decleration tag at the top saying that tags beginning with <c: belong to the core JSTL library?

7

Actually i had it missing. However i added it, and it was still displaying null.

Someone checked my EJB and it seemed ok, so i guess it is a problem in my action.

A question:

What i did was

  • Call method which returns arraylist of objects
  • Set arraylist object in session using reqiest.setAttribute()

This means i do not use any actionform.

Now, without modifying any code, just adding jstl taglib, i get

<table border="1">

        </table>

When i click view source in JSP. The above appears.

This is my action.

BookingLineActionForm bookinglineform = (BookingLineActionForm) form; // get the form bean
        Bookingline bookingline = new Bookingline();
        //ArrayList mylist = new ArrayList();

        String placefrom = bookinglineform.getBkLPlaceFrom();
        String placeto = bookinglineform.getBkLPlaceTo();


        bookingline = lookupBookinglineFacade().tripSearch(placefrom,placeto);
        //BeanUtils.copyProperties(bookinglineform,bookingline);

       request.setAttribute("bookingList", bookingline);

       //request.setAttribute("bookingList",lookupBookinglineFacade().tripSearch(placefrom,placeto));
8