How to show elements of a SET in JSP

Question

I am dealing with a legacy system that has track of all past exams and the topics that has been covered in each.

For example:

Exam1 1/1/1980
topicID topicName topicRFCode  Description
1         AAA         1         fdfdfgfdgdf
1         AAA         2         cvcvcvcvcv
20        XXX         1         asasasasas
12        MMM         3         klklklkl
12        MMM         1         erererer
12        MMM         2         jkjkjkjkjkjk

As you can see, three different topics were covered in 1/1/1980 exam. Two questions were related to topic AAA One question was related to topic XXX and three questions were related to topic MMM.

Java passes a list of topics that are related to the selected exam to JSP then I try to show descriptions of each topic separately, I have following

       <c:forEach var="topic" items="${topics}" >
            <c:if test="${topic.topicId == '1'}">
                <c:forEach var="aaa" items="${topics}">
                        <c:if test="${aaa.topicId == '1'}">
                            <p>${aaa.description}</p>
                        </c:if>
                </c:forEach>
            </c:if>
</c:forEach>

The problems are:

Current code has two for loops so for each topic I should have a separate pair of codes as I want to show all descriptions for each topic one after another.
Because of multiple for loops it is quite slow.
Not sure if this is the best approach to the issue.

Whats the issue? whats the down vote for? – Jack Apr 20 '15 at 05:08 — Jack, Apr 20 '15 at 05:08

score 2 · Accepted Answer · edited May 23 '17 at 11:58

2

Instead of passing list, you can pass Map of List of Topic.

Map<String, List<Topic>> // Key as topicID

For how to iterate Map, you can refer this answer by @BalusC.

edited May 23 '17 at 11:58

Community

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answered Apr 20 '15 at 05:08

Naman Gala

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Cool, then how to iterate through it? how does this help? – Jack Apr 20 '15 at 05:10
You can iterate Map and print its inside list content. – Naman Gala Apr 20 '15 at 05:12

How to show elements of a SET in JSP

1 Answers1