how to get the size of a HashMap using jstl

I开发者_JAVA技巧s there any way to get the size of a Map using JSTL ? I tried with ${myMap.size} but it's not working..

got the solution: Use jstl functions.

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

then use like this:

  <c:if test="${fn:length(myMap) > 1 }">

${myMap.size}

isn't working because it gets translated to myMap.getSize() by the EL parser.

Try:

${myMap.size()}

It should work.

The JSTL length function works on a Collection but not sure if it will work on a Map. Might be worth a try.

You can see an example to find the JSTL HashMap size here

We are using HashMap size method here

${numMap.size()}

If you are trying to just print the count - then you have to use fn tags. But if you want to process all the items in a map or do something based on the number of items available, try this using only core JSTL tag:

<c:if test="${mapVar != null}"/>
<c:forEach var="mapEntry" items="${mapVar}">
<!-- if there is any entry in the map do something -->
</c:forEach>
</c:if>

The above is equivalent to Java Code

if (maVar != null && mapVar.size() >= 1) {
    // do something
}

Yes you cannot print out the size like this, but you can still process information of the items exist.

I prefered this solution because that SUN url errors out so the above worked for me.