Question

I have an object (collection) that I am putting into request before constructing a JSP page based on the state of the object.

        Map<Integer, QuestionBO> questionsIdsMap = new TreeMap<Integer, QuestionBO>();

        for (QuestionBO question : questionsForSubject) {
            questionsIdsMap.put(question.getQuestionId(), question);                
        } 

        request.setAttribute("questionsForSubject", questionsIdsMap);

Then I do some manipulations with the form and submit the whole page back to the servlet for processing.

    <jsp:useBean id="questionsForSubject" class="java.util.Map" scope="request"/>

    <c:if test="${not empty questionsForSubject}">
    <form  action="/TutorWebApp/controller" method="POST" name="addQuestionForm">
        <input type="hidden" name="command" value="add_question_list" />
        <input type="hidden" name="testName" value="${testName}"/> 
        <input type="hidden" name="questionsForSubject" value="${questionsForSubject}"/>
        <table border ="1">
            <tbody>
                <c:forEach items="${questionsForSubject.keySet()}" var="questionID">
                    <tr>
                        <td>
                            <input type="checkbox" name ="choosen_question" value="${questionID}">
                            ${questionsForSubject.get(questionID).getQuestion()}
                            <br />
                        </td>
                    </tr>
                </c:forEach>
            </tbody>
        </table>
        <input type="submit" value="Add questions"/>              
    </form> 
    </c:if>  

What is the conventional way of passing of the previously mentioned collection to make it available on the servlet-side?

I should do it without any frameworks.

Answer 1

Since you have used

request.setAttribute("questionsForSubject", questionsIdsMap);

you don’t need to use the jsp:useBean tag.
For the display, try

<c:forEach items="${questionsForSubject}" var="current">
                <tr>
                    <td>
                        <input type="checkbox" name ="choosen_question" value="${current.key}">
                        ${current.value}
                        <br />
                    </td>
                </tr>
</c:forEach>