Use <c:forEach> with HashMap

java jsp jstl

jonasespelita · Feb 5, 2010 · Viewed 85.1k times · Source

I have a java class that sets an servlet attribute to a HashMap object:

request.setAttribute("types", da.getSecurityTypes());

where request is an HttpServletRequest Object, and da.getSecurityTypes() returns a HashMap Object.

Is there a way to go through the HashMap collection using c:foreach or some other JSTL tags?

I was thinking:

 <c:forEach var="type" items="${types}">
                 ...
     </c:forEach>

Or if it can't be done, how would one make a custom tag to process this?

Resorting to Java code in my JSP page is be my last resort and I'd like to know if this is possible with JSTL.

Thanks, Jonas.

Answer

Yes, this is perfectly acceptable.

When you use <c:forEach> to iterate over a Map, each item in the iteration is an instance of Map.Entry. So given your example:

<c:forEach var="type" items="${types}">
   Key is ${type.key}
   Value is ${type.value}
</c:forEach>