*/
public class TagUtils {
public static ValueStack getStack(PageContext pageContext) {
HttpServletRequest req = (HttpServletRequest) pageContext.getRequest();
ValueStack stack = (ValueStack) req.getAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY);
if (stack == null) {
HttpServletResponse res = (HttpServletResponse) pageContext.getResponse();
Dispatcher du = Dispatcher.getInstance();
if (du == null) {
throw new ConfigurationException("The Struts dispatcher cannot be found. This is usually caused by "+
"using Struts tags without the associated filter. Struts tags are only usable when the request "+
"has passed through its servlet filter, which initializes the Struts dispatcher needed for this tag.");
}
stack = du.getContainer().getInstance(ValueStackFactory.class).createValueStack();
Map<String, Object> extraContext = du.createContextMap(new RequestMap(req),
req.getParameterMap(),
new SessionMap(req),
new ApplicationMap(pageContext.getServletContext()),
req,
res,
pageContext.getServletContext());
extraContext.put(ServletActionContext.PAGE_CONTEXT, pageContext);
stack.getContext().putAll(extraContext);
req.setAttribute(ServletActionContext.STRUTS_VALUESTACK_KEY, stack);
// also tie this stack/context to the ThreadLocal
ActionContext.setContext(new ActionContext(stack.getContext()));
} else {
// let's make sure that the current page context is in the action context
Map<String, Object> context = stack.getContext();
context.put(ServletActionContext.PAGE_CONTEXT, pageContext);
AttributeMap attrMap = new AttributeMap(context);
context.put("attr", attrMap);
}