在自定义JSP模板中使用Struts 2 taglib实施邮件模板

Question

I'm building an app that leverages Struts2 as the primary framework, but one of the requirements is that the app sends automated emails.

Since Struts2 doesn't include much helpfulness out-of-the-box in terms of implementing mail templates, I decided to just use normal JSP, like this:

public static String parseJSPTemplate(String jspPath, HttpServletRequest req) throws ServletException, IOException {
    RequestDispatcher jsp = req.getRequestDispatcher(jspPath);
    EmailTemplateHandler tpl = new EmailTemplateHandler();
    jsp.forward(req, tpl);
    return tpl.toString();
}

So, this processes the JSP in a normal way and returns a string representation of the output with variables replaced, etc.

One would think that including the Struts2 taglib per usual (eg <%@ taglib prefix="s" uri="/struts-tags" %> ) would allow the use of tags like <s:url /> ; however, it seems that this is not the case. Instead, the result of the call to the taglib is blank. No errors are displayed nor exceptions thrown.

My guess is that something else needs to be injected into the request before Struts2 will properly respond to calls, but I'm not sure what this would be.

Anyone have an idea on how to get this working? Other taglibs like JSTL-core work fine.

Answer 1

Struts tags are working if the ActionContext is available. Normally it's created by the Dispatcher in prepare operations. So, the struts2 filter should be mapped to accept DispatcherType.FORWARD requests to be invoked on your forward. You can also get the action context via ActionContext.getContext() in the JSP for debugging.