Get value from hashmap based on key to JSTL

if all you're trying to do is get the value of a single entry in a map, there's no need to loop over any collection at all. simplifying gautum's response slightly, you can get the value of a named map entry as follows:

<c:out value="${map['key']}"/>

where 'map' is the collection and 'key' is the string key for which you're trying to extract the value.

could you please try below code

<c:forEach var="hash" items="${map['key']}">
        <option><c:out value="${hash}"/></option>
  </c:forEach>