How to select the first element of a set with JSTL?

user_2138 0
Viewed 112804

I managed to do it with the next code but there must be an easier way. 

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>


<c:if test="${fn:length(attachments) > 0}">
    <c:forEach var="attachment" items="${attachments}" varStatus="loopCount">
        <c:if test="${loopCount.count eq 1}">
         attachment.id
        </c:if>
    </c:forEach>
</c:if>
jakarta-ee jstl
10 Answers

You can access individual elements with the array [] operator:

<c:out value="${attachments[0].id}" />

This will work for arrays and lists. It won't work for maps and sets. In that case you must put the key of the element inside the brackets.

user_240540

You can use the EL 3.0 Stream API.

<div>${attachments.stream().findFirst().get()}</div>

Be careful! The EL 3.0 Stream API was finalized before the Java 8 Stream API and it is different than that. They can't sunc both apis because it will break the backward compatibility.

user_11235010

If it's a set ${attachments[0].id} won't work. use this instead

${attachments.first().key} or ${attachments.first().value}

user_120819170
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