title: JSP programmatically render
body: <p>I need to programmatically render JSP page. As far as I understand, JSP should have some compiler. The question is can I use this compiler dirrectly without JspServlet and others? All I need is documentation how to use JSP compiler (Jasper, for example).</p>
  
  <p>Some additional information would clarify situation, I think. I can not use standard JspServlet. I want to change source JSP before compilation in some way (merge two JSP together to be precise), so I need a way to compile JSP result from InputStream (or Reader) using the JSP compiler directly.</p>
  
  <p>Merging of two JSP is layout requirement. You can ask: "But why this guy just doesn't use SiteMesh or something like this?". One of JSP pages is not static. It's provided by user and stored in database. We sanitify and validates this JSP layout (users are able to use only subset of tags, and all of them are not standart but created specially for them), cache them and so on. But now we need a way to use these JSP pages (which are stored in memory) as layouts for all JSP pages that user request.</p>