else if (collection instanceof Iterator)
iterator = (Iterator) collection;
else if (collection instanceof Map)
iterator = ((Map) collection).entrySet().iterator();
else if (collection instanceof Enumeration)
iterator = new IteratorAdapter((Enumeration)collection);
else {
JspException e = new JspException
(messages.getMessage("iterate.iterator"));
RequestUtils.saveException(pageContext, e);
throw e;