JSP Insert footer based on condition in for loop

Question

I want to loop a table of records for printing, based on the following condition:

If the number of records is more than 35, I will need to pause the loop, insert a footer, and a new header for the next page and continue its count till the last record.

The condition here is to use only jsp classic scriplet.

Here is what I have and I am stuck: (in pseudo code format)

<% int j=0;
   for(int i=0; i < list.size(); i++){
    col1 = list.get(i).getItem1();
    col2 = list.get(i).getItem2();
    col3 = list.get(i).getItem3();
    j++;

    if (j==35) {%> // stops to render footer and next page's header 
    </table>
    <table>
       <!-- footer contents -->
    </table>
    <table>
       <!-- header for next page -->
    </table>
    <%}%>
<tr><td><%=col1%></td><td><%=col1%></td><td><%=col1%></td></tr>

<%}%>

the problem with this model is that if I use a break inside this if, I'd stop the loop and I can't loop from record #36 to end of record. How do I go about doing this?

Answer 1

Use an if (i % 35 == 0) to write the footer and then validate if there are more elements in the list so you would have to add a new table and its header. The code would look like this:

<!-- table header -->
<%
int size = list.size();
int i = 0;
for(Iterator<YourObject> it = list.iterator(); it.hasNext(); ) {
    i++;
    YourObject someObject = it.next();
    col1 = someObject.getItem1();
    col2 = someObject.getItem2();
    col3 = someObject.getItem3();
    if (i % 35 == 0) {
%>
    <!-- table footer -->
<%
        if (i < size) {
%>
    <!-- breakline and new table header -->
<%
        }
    }
}
%>
<!-- table footer -->

Note that in this code sample I'm using Iterator instead of List#get(int index) since if your List is a LinkedList internally it would need to traverse all the elements until reach the element on the desired index (in this case, i ). With this implementation, your code is even cleaner.

Answer 2

If you don't want to use proper pagination then use JSTL as below. Easier to read than scrip-lets as well, apart from the obvious benefits.

//The counter variable initialization
<c:set var="counter" value="0" scope="page"/>
<c:forEach items="${itemList}" var="item">

  //Counter increment
  <c:set var="counter" value="${counter + 1}" scope="page"/>
  <tr>
    <td>${item.propertyOne}</td>
    <td>${item.propertyOne}</td>
  </tr>
  <c:if test="${counter % 35 == 0}">
    //Include your footer here.
  </c:if>
</c:forEach>