[xwiki-devs] best practice to programme with XWiki objects?

hello fellow developers, at Curriki, we are starting to process XWiki objects in the background using subclasses of AbstractXWikiRunnable. Currently I do the following: // setup XWikiContext xcontext = (XWikiContext) Utils.getComponent(Execution.class).getContext() .getProperty(XWikiContext.EXECUTIONCONTEXT_KEY); Context context = new Context(xcontext); XWiki xwiki = new com.xpn.xwiki.api.XWiki(context.getXWiki(), xcontext); // fetch background info Document d = xwiki.getDocument(DOCNAME_x); Object obj = d.getObject("DOCNAME_class"); // modify something // save d.save("comment"); However, I wonder if this is the best practice: - is it expensive to construct a context and xwiki supposing this setup code is run multiple times? - is it preferrable to work with the com.xpn.xwiki.* classes? - is DocReference behaving much differently than fullName if we have a single wiki? Thanks in advance. Paul